Show debug logs in authentication (#325)

Bumps [github.com/int128/oauth2cli](https://github.com/int128/oauth2cli) from 1.11.0 to 1.12.1.
- [Release notes](https://github.com/int128/oauth2cli/releases)
- [Commits](https://github.com/int128/oauth2cli/compare/v1.11.0...v1.12.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

.circleci/config.yml

@@ -1,27 +1,60 @@
-version: 2
+version: 2.1
+
 jobs:
-  build:
+  test:
     docker:
-      - image: circleci/golang:1.14.1
+      - image: cimg/go:1.14.4
     steps:
-      - run: mkdir -p ~/bin
-      - run: echo 'export PATH="$HOME/bin:$PATH"' >> $BASH_ENV
+      - run: curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(go env GOPATH)/bin v1.24.0
       - checkout
-      - run: make ci-setup-linux-amd64
-      - run: make VERSION=$CIRCLE_TAG ci
-      - run: |
-          if [ "$CIRCLE_TAG" ]; then
-            make VERSION=$CIRCLE_TAG GITHUB_USERNAME=$CIRCLE_PROJECT_USERNAME GITHUB_REPONAME=$CIRCLE_PROJECT_REPONAME release
-          fi
+      - restore_cache:
+          keys:
+            - go-sum-{{ checksum "go.sum" }}
+      - run: make check
+      - run: bash <(curl -s https://codecov.io/bash)
+      - save_cache:
+          key: go-sum-{{ checksum "go.sum" }}
+          paths:
+            - ~/go/pkg
       - store_artifacts:
           path: gotest.log
 
+  crossbuild:
+    macos:
+      xcode: 11.5.0
+    steps:
+      - run: |
+          curl -sSfL https://dl.google.com/go/go1.14.4.darwin-amd64.tar.gz | tar -C /tmp -xz
+          echo 'export PATH="$PATH:/tmp/go/bin:$HOME/go/bin"' >> $BASH_ENV
+      - checkout
+      - restore_cache:
+          keys:
+            - go-macos-{{ checksum "go.sum" }}
+      - run:
+          command: go get -v github.com/int128/goxzst github.com/int128/ghcp
+          working_directory: .circleci
+      - run: make dist
+      - run: |
+          if [ "$CIRCLE_TAG" ]; then
+            make release
+          fi
+      - save_cache:
+          key: go-macos-{{ checksum "go.sum" }}
+          paths:
+            - ~/go/pkg
+
 workflows:
   version: 2
-  all:
+  build:
     jobs:
-      - build:
-          context: open-source
+      - test:
+          filters:
+            tags:
+              only: /.*/
+      - crossbuild:
+          context: open-source
+          requires:
+            - test
           filters:
             tags:
               only: /.*/

.circleci/go.mod

@@ -0,0 +1,3 @@
+module github.com/int128/kubelogin/.circleci
+
+go 1.13

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,23 @@
+---
+name: Bug report
+about: Create a report to help us improve
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior.
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Environment**
+ - OS: [e.g. macOS, Linux]
+ - kubelogin version: [e.g. 1.19.3]
+ - kubectl version: [e.g. 1.19]
+ - OpenID Connect provider: [e.g. Google, Okta]

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,17 @@
+---
+name: Feature request
+about: Suggest an idea for this project
+title: ''
+labels: enhancement
+assignees: ''
+
+---
+
+**Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+**Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+**Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.

.github/workflows/system-test.yaml

@@ -1,8 +1,6 @@
-name: acceptance-test
 on: [push]
 jobs:
-  build:
-    name: test
+  system-test:
     # https://help.github.com/en/actions/automating-your-workflow-with-github-actions/software-installed-on-github-hosted-runners#ubuntu-1804-lts
     runs-on: ubuntu-18.04
     steps:
@@ -19,12 +17,13 @@ jobs:
             go-
       # https://kind.sigs.k8s.io/docs/user/quick-start/
       - run: |
-          wget -q -O ./kind "https://github.com/kubernetes-sigs/kind/releases/download/v0.7.0/kind-linux-amd64"
+          wget -q -O ./kind "https://github.com/kubernetes-sigs/kind/releases/download/v0.8.1/kind-linux-amd64"
           chmod +x ./kind
           sudo mv ./kind /usr/local/bin/kind
           kind version
       # https://packages.ubuntu.com/xenial/libnss3-tools
+      - run: sudo apt update
       - run: sudo apt install -y libnss3-tools
       - run: echo '127.0.0.1 dex-server' | sudo tee -a /etc/hosts
-      - run: make -C acceptance_test -j3 setup
-      - run: make -C acceptance_test test
+      - run: make -C system_test -j3 setup
+      - run: make -C system_test test

.gitignore

@@ -1,5 +1,6 @@
 /.idea
 
+/system_test/output/
 /acceptance_test/output/
 
 /dist/output

Makefile

@@ -1,10 +1,11 @@
-# CI must provide the following variables (on tag push)
-# VERSION
-# GITHUB_USERNAME
-# GITHUB_REPONAME
+# CircleCI specific variables
+CIRCLE_TAG ?= latest
+GITHUB_USERNAME := $(CIRCLE_PROJECT_USERNAME)
+GITHUB_REPONAME := $(CIRCLE_PROJECT_REPONAME)
 
 TARGET := kubelogin
-VERSION ?= latest
+TARGET_OSARCH := linux_amd64 darwin_amd64 windows_amd64 linux_arm linux_arm64
+VERSION ?= $(CIRCLE_TAG)
 LDFLAGS := -X main.version=$(VERSION)
 
 all: $(TARGET)
@@ -12,12 +13,6 @@ all: $(TARGET)
 $(TARGET): $(wildcard **/*.go)
 	go build -o $@ -ldflags "$(LDFLAGS)"
 
-.PHONY: ci
-ci:
-	$(MAKE) check
-	bash -c "bash <(curl -s https://codecov.io/bash)"
-	$(MAKE) dist
-
 .PHONY: check
 check:
 	golangci-lint run
@@ -27,7 +22,7 @@ check:
 dist: dist/output
 dist/output:
 	# make the zip files for GitHub Releases
-	VERSION=$(VERSION) CGO_ENABLED=0 goxzst -d dist/output -i "LICENSE" -o "$(TARGET)" -t "dist/kubelogin.rb dist/oidc-login.yaml dist/Dockerfile" -- -ldflags "$(LDFLAGS)"
+	VERSION=$(VERSION) goxzst -d dist/output -i "LICENSE" -o "$(TARGET)" -osarch "$(TARGET_OSARCH)" -t "dist/kubelogin.rb dist/oidc-login.yaml dist/Dockerfile" -- -ldflags "$(LDFLAGS)"
 	# test the zip file
 	zipinfo dist/output/kubelogin_linux_amd64.zip
 	# make the krew yaml structure
@@ -52,15 +47,3 @@ clean:
 	-rm $(TARGET)
 	-rm -r dist/output/
 	-rm coverage.out gotest.log
-
-.PHONY: ci-setup-linux-amd64
-ci-setup-linux-amd64:
-	mkdir -p ~/bin
-	# https://github.com/golangci/golangci-lint
-	curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | sh -s -- -b ~/bin v1.24.0
-	# https://github.com/int128/goxzst
-	curl -sfL -o /tmp/goxzst.zip https://github.com/int128/goxzst/releases/download/v0.3.0/goxzst_linux_amd64.zip
-	unzip /tmp/goxzst.zip -d ~/bin
-	# https://github.com/int128/ghcp
-	curl -sfL -o /tmp/ghcp.zip https://github.com/int128/ghcp/releases/download/v1.8.0/ghcp_linux_amd64.zip
-	unzip /tmp/ghcp.zip -d ~/bin

README.md

@@ -1,10 +1,10 @@
-# kubelogin [![CircleCI](https://circleci.com/gh/int128/kubelogin.svg?style=shield)](https://circleci.com/gh/int128/kubelogin) ![acceptance-test](https://github.com/int128/kubelogin/workflows/acceptance-test/badge.svg) [![Go Report Card](https://goreportcard.com/badge/github.com/int128/kubelogin)](https://goreportcard.com/report/github.com/int128/kubelogin)
+# kubelogin [![CircleCI](https://circleci.com/gh/int128/kubelogin.svg?style=shield)](https://circleci.com/gh/int128/kubelogin) [![Go Report Card](https://goreportcard.com/badge/github.com/int128/kubelogin)](https://goreportcard.com/report/github.com/int128/kubelogin)
 
 This is a kubectl plugin for [Kubernetes OpenID Connect (OIDC) authentication](https://kubernetes.io/docs/reference/access-authn-authz/authentication/#openid-connect-tokens), also known as `kubectl oidc-login`.
 
 Here is an example of Kubernetes authentication with the Google Identity Platform:
 
-<img alt="screencast" src="https://user-images.githubusercontent.com/321266/70971501-7bcebc80-20e4-11ea-8afc-539dcaea0aa8.gif" width="652" height="455">
+<img alt="screencast" src="https://user-images.githubusercontent.com/321266/85427290-86e43700-b5b6-11ea-9e97-ffefd736c9b7.gif" width="572" height="391">
 
 Kubelogin is designed to run as a [client-go credential plugin](https://kubernetes.io/docs/reference/access-authn-authz/authentication/#client-go-credential-plugins).
 When you run kubectl, kubelogin opens the browser and you can log in to the provider.
@@ -18,19 +18,14 @@ Take a look at the diagram:
 
 ### Setup
 
-Install the latest release from [Homebrew](https://brew.sh/), [Krew](https://github.com/kubernetes-sigs/krew) or [GitHub Releases](https://github.com/int128/kubelogin/releases) as follows:
+Install the latest release from [Homebrew](https://brew.sh/), [Krew](https://github.com/kubernetes-sigs/krew) or [GitHub Releases](https://github.com/int128/kubelogin/releases).
 
 ```sh
-# Homebrew
+# Homebrew (macOS and Linux)
 brew install int128/kubelogin/kubelogin
 
-# Krew
+# Krew (macOS, Linux, Windows and ARM)
 kubectl krew install oidc-login
-
-# GitHub Releases
-curl -LO https://github.com/int128/kubelogin/releases/download/v1.18.0/kubelogin_linux_amd64.zip
-unzip kubelogin_linux_amd64.zip
-ln -s kubelogin kubectl-oidc_login
 ```
 
 You need to set up the OIDC provider, cluster role binding, Kubernetes API server and kubeconfig.
@@ -51,7 +46,7 @@ users:
       - --oidc-client-secret=YOUR_CLIENT_SECRET
 ```
 
-See [the setup guide](docs/setup.md) for more.
+See [setup guide](docs/setup.md) for more.
 
 
 ### Run
@@ -88,21 +83,26 @@ If the refresh token has expired, kubelogin will perform reauthentication.
 You can log out by removing the token cache directory (default `~/.kube/cache/oidc-login`).
 Kubelogin will perform authentication if the token cache file does not exist.
 
-You can dump the claims of token by passing `-v1` option.
+You can dump claims of an ID token by `setup` command.
 
-```
-I0221 21:54:08.151850   28231 get_token.go:104] you got a token: {
+```console
+% kubectl oidc-login setup --oidc-issuer-url https://accounts.google.com --oidc-client-id REDACTED --oidc-client-secret REDACTED
+authentication in progress...
+
+## 2. Verify authentication
+
+You got a token with the following claims:
+
+{
   "sub": "********",
   "iss": "https://accounts.google.com",
   "aud": "********",
-  "iat": 1582289639,
-  "exp": 1582293239,
-  "jti": "********",
-  "nonce": "********",
-  "at_hash": "********"
+  ...
 }
 ```
 
+You can verify kubelogin works with your provider using [acceptance test](acceptance_test).
+
 
 ## Usage
 
@@ -128,6 +128,7 @@ Flags:
       --listen-address strings                          Address to bind to the local server. If multiple addresses are given, it will try binding in order (default [127.0.0.1:8000,127.0.0.1:18000])
       --listen-port ints                                (Deprecated: use --listen-address)
       --skip-open-browser                               If true, it does not open the browser on authentication
+      --oidc-redirect-url-hostname string               Hostname of the redirect URL (default "localhost")
       --oidc-auth-request-extra-params stringToString   Extra query parameters to send with an authentication request (default [])
       --username string                                 If set, perform the resource owner password credentials grant
       --password string                                 If set, use the password instead of asking it
@@ -192,6 +193,12 @@ You can change the listening address.
       - --listen-address=127.0.0.1:23456
 ```
 
+You can change the hostname of redirect URI from the default value `localhost`.
+
+```yaml
+      - --oidc-redirect-url-hostname=127.0.0.1
+```
+
 You can add extra parameters to the authentication request.
 
 ```yaml
@@ -281,7 +288,7 @@ users:
       - /tmp/.token-cache:/.token-cache
       - -p
       - 8000:8000
-      - quay.io/int128/kubelogin:v1.18.0
+      - quay.io/int128/kubelogin
       - get-token
       - --token-cache-dir=/.token-cache
       - --listen-address=0.0.0.0:8000
@@ -321,4 +328,4 @@ make
 ./kubelogin
 ```
 
-See also [the acceptance test](acceptance_test).
+See also [the system test](system_test).

acceptance_test/Makefile

@@ -1,99 +1,31 @@
 CLUSTER_NAME := kubelogin-acceptance-test
 OUTPUT_DIR := $(CURDIR)/output
 
-PATH := $(PATH):$(OUTPUT_DIR)/bin
-export PATH
 KUBECONFIG := $(OUTPUT_DIR)/kubeconfig.yaml
 export KUBECONFIG
 
-# run the login script instead of opening chrome
-BROWSER := $(OUTPUT_DIR)/bin/chromelogin
-export BROWSER
-
-.PHONY: test
-test: build
-	# see the setup instruction
-	kubectl oidc-login setup \
-		--oidc-issuer-url=https://dex-server:10443/dex \
-		--oidc-client-id=YOUR_CLIENT_ID \
-		--oidc-client-secret=YOUR_CLIENT_SECRET \
-		--oidc-extra-scope=email \
-		--certificate-authority=$(OUTPUT_DIR)/ca.crt
-	# set up the kubeconfig
-	kubectl config set-credentials oidc \
-		--exec-api-version=client.authentication.k8s.io/v1beta1 \
-		--exec-command=kubectl \
-		--exec-arg=oidc-login \
-		--exec-arg=get-token \
-		--exec-arg=--oidc-issuer-url=https://dex-server:10443/dex \
-		--exec-arg=--oidc-client-id=YOUR_CLIENT_ID \
-		--exec-arg=--oidc-client-secret=YOUR_CLIENT_SECRET \
-		--exec-arg=--oidc-extra-scope=email \
-		--exec-arg=--certificate-authority=$(OUTPUT_DIR)/ca.crt
-	# make sure we can access the cluster
-	kubectl --user=oidc cluster-info
-	# switch the current context
-	kubectl config set-context --current --user=oidc
-	# make sure we can access the cluster
-	kubectl cluster-info
-
-.PHONY: setup
-setup: build dex cluster setup-chrome
-
-.PHONY: setup-chrome
-setup-chrome: $(OUTPUT_DIR)/ca.crt
-	# add the dex server certificate to the trust store
-	mkdir -p ~/.pki/nssdb
-	cd ~/.pki/nssdb && certutil -A -d sql:. -n dex -i $(OUTPUT_DIR)/ca.crt -t "TC,,"
-
-# build binaries
-.PHONY: build
-build: $(OUTPUT_DIR)/bin/kubectl-oidc_login $(OUTPUT_DIR)/bin/chromelogin
-$(OUTPUT_DIR)/bin/kubectl-oidc_login:
-	go build -o $@ ..
-$(OUTPUT_DIR)/bin/chromelogin: chromelogin/main.go
-	go build -o $@ ./chromelogin
-
-# create a Dex server
-.PHONY: dex
-dex: $(OUTPUT_DIR)/server.crt $(OUTPUT_DIR)/server.key
-	docker create --name dex-server -p 10443:10443 quay.io/dexidp/dex:v2.21.0 serve /dex.yaml
-	docker cp $(OUTPUT_DIR)/server.crt dex-server:/
-	docker cp $(OUTPUT_DIR)/server.key dex-server:/
-	docker cp dex.yaml dex-server:/
-	docker start dex-server
-	docker logs dex-server
-
-$(OUTPUT_DIR)/ca.key:
-	mkdir -p $(OUTPUT_DIR)
-	openssl genrsa -out $@ 2048
-$(OUTPUT_DIR)/ca.csr: $(OUTPUT_DIR)/ca.key
-	openssl req -new -key $(OUTPUT_DIR)/ca.key -out $@ -subj "/CN=dex-ca" -config openssl.cnf
-$(OUTPUT_DIR)/ca.crt: $(OUTPUT_DIR)/ca.key $(OUTPUT_DIR)/ca.csr
-	openssl x509 -req -in $(OUTPUT_DIR)/ca.csr -signkey $(OUTPUT_DIR)/ca.key -out $@ -days 10
-$(OUTPUT_DIR)/server.key:
-	mkdir -p $(OUTPUT_DIR)
-	openssl genrsa -out $@ 2048
-$(OUTPUT_DIR)/server.csr: openssl.cnf $(OUTPUT_DIR)/server.key
-	openssl req -new -key $(OUTPUT_DIR)/server.key -out $@ -subj "/CN=dex-server" -config openssl.cnf
-$(OUTPUT_DIR)/server.crt: openssl.cnf $(OUTPUT_DIR)/server.csr $(OUTPUT_DIR)/ca.crt $(OUTPUT_DIR)/ca.key
-	openssl x509 -req -in $(OUTPUT_DIR)/server.csr -CA $(OUTPUT_DIR)/ca.crt -CAkey $(OUTPUT_DIR)/ca.key -CAcreateserial -out $@ -sha256 -days 10 -extensions v3_req -extfile openssl.cnf
-
 # create a Kubernetes cluster
 .PHONY: cluster
-cluster: dex create-cluster
-	# add the Dex container IP to /etc/hosts of kube-apiserver
-	docker inspect -f '{{.NetworkSettings.IPAddress}}' dex-server | sed -e 's,$$, dex-server,' | \
-		kubectl -n kube-system exec -i kube-apiserver-$(CLUSTER_NAME)-control-plane -- tee -a /etc/hosts
-	# wait for kube-apiserver oidc initialization
-	# (oidc authenticator will retry oidc discovery every 10s)
-	sleep 10
-
-.PHONY: create-cluster
-create-cluster: $(OUTPUT_DIR)/ca.crt
-	cp $(OUTPUT_DIR)/ca.crt /tmp/kubelogin-acceptance-test-dex-ca.crt
-	kind create cluster --name $(CLUSTER_NAME) --config cluster.yaml
-	kubectl apply -f role.yaml
+cluster:
+	# create a cluster
+	mkdir -p $(OUTPUT_DIR)
+	sed -e "s|OIDC_ISSUER_URL|$(OIDC_ISSUER_URL)|" -e "s|OIDC_CLIENT_ID|$(OIDC_CLIENT_ID)|" cluster.yaml > $(OUTPUT_DIR)/cluster.yaml
+	kind create cluster --name $(CLUSTER_NAME) --config $(OUTPUT_DIR)/cluster.yaml
+	# set up access control
+	kubectl create clusterrole cluster-readonly --verb=get,watch,list --resource='*.*'
+	kubectl create clusterrolebinding cluster-readonly --clusterrole=cluster-readonly --user=$(YOUR_EMAIL)
+	# set up kubectl
+	kubectl config set-credentials oidc \
+		--exec-api-version=client.authentication.k8s.io/v1beta1 \
+		--exec-command=$(CURDIR)/../kubelogin \
+		--exec-arg=get-token \
+		--exec-arg=--token-cache-dir=$(OUTPUT_DIR)/token-cache \
+		--exec-arg=--oidc-issuer-url=$(OIDC_ISSUER_URL) \
+		--exec-arg=--oidc-client-id=$(OIDC_CLIENT_ID) \
+		--exec-arg=--oidc-client-secret=$(OIDC_CLIENT_SECRET) \
+		--exec-arg=--oidc-extra-scope=email
+	# switch the default user
+	kubectl config set-context --current --user=oidc
 
 # clean up the resources
 .PHONY: clean
@@ -102,7 +34,9 @@ clean:
 .PHONY: delete-cluster
 delete-cluster:
 	kind delete cluster --name $(CLUSTER_NAME)
-.PHONY: delete-dex
-delete-dex:
-	docker stop dex-server
-	docker rm dex-server
+
+.PHONY: check
+check:
+	docker version
+	kind version
+	kubectl version --client

acceptance_test/README.md

@@ -1,109 +1,75 @@
 # kubelogin/acceptance_test
 
-This is an acceptance test for walkthrough of the OIDC initial setup and plugin behavior using a real Kubernetes cluster and OpenID Connect provider, running on [GitHub Actions](https://github.com/int128/kubelogin/actions?query=workflow%3Aacceptance-test).
-
-It is intended to verify the following points:
-
-- User can set up Kubernetes OIDC authentication and this plugin.
-- User can access a cluster after login.
-
-It performs the test using the following components:
-
-- Kubernetes cluster (Kind)
-- OIDC provider (Dex)
-- Browser (Chrome)
-- kubectl command
+This is a manual test for verifying Kubernetes OIDC authentication with your OIDC provider.
 
 
-## How it works
+## Purpose
 
-Let's take a look at the diagram.
+This test checks the following points:
 
-![diagram](../docs/acceptance-test-diagram.svg)
-
-It prepares the following resources:
-
-1. Generate a pair of CA certificate and TLS server certificate for Dex.
-1. Run Dex on a container.
-1. Create a Kubernetes cluster using Kind.
-1. Mutate `/etc/hosts` of the CI machine to access Dex.
-1. Mutate `/etc/hosts` of the kube-apiserver pod to access Dex.
-
-It performs the test by the following steps:
-
-1. Run kubectl.
-1. kubectl automatically runs kubelogin.
-1. kubelogin automatically runs [chromelogin](chromelogin).
-1. chromelogin opens the browser, navigates to `http://localhost:8000` and enter the username and password.
-1. kubelogin gets an authorization code from the browser.
-1. kubelogin gets a token.
-1. kubectl accesses an API with the token.
-1. kube-apiserver verifies the token by Dex.
-1. Check if kubectl exited with code 0.
+1. You can set up your OIDC provider using [setup guide](../docs/setup.md).
+1. The plugin works with your OIDC provider.
 
 
-## Run locally
+## Getting Started
 
-You need to set up the following components:
+### Prerequisite
+
+You need to build the plugin into the parent directory.
+
+```sh
+make -C ..
+```
+
+You need to set up your provider.
+See [setup guide](../docs/setup.md) for more.
+
+You need to install the following tools:
 
 - Docker
 - Kind
-- Chrome or Chromium
+- kubectl
 
-You need to add the following line to `/etc/hosts` so that the browser can access the Dex.
+You can check if the tools are available.
 
-```
-127.0.0.1 dex-server
+```sh
+make check
 ```
 
-Run the test.
+### 1. Create a cluster
 
-```shell script
-# run the test
-make
+Create a cluster.
+For example, you can create a cluster with Google account authentication.
 
-# clean up
+```sh
+make OIDC_ISSUER_URL=https://accounts.google.com \
+  OIDC_CLIENT_ID=REDACTED.apps.googleusercontent.com \
+  OIDC_CLIENT_SECRET=REDACTED \
+  YOUR_EMAIL=REDACTED@gmail.com
+```
+
+It will do the following steps:
+
+1. Create a cluster.
+1. Set up access control. It allows read-only access from your email address.
+1. Set up kubectl to enable the plugin.
+
+You can change kubectl configuration in generated `output/kubeconfig.yaml`.
+
+### 2. Run kubectl
+
+Make sure you can log in to the provider and access the cluster.
+
+```console
+% export KUBECONFIG=$PWD/output/kubeconfig.yaml
+% kubectl get pods -A
+```
+
+### Clean up
+
+To delete the cluster and generated files:
+
+```sh
 make delete-cluster
-make delete-dex
+make clean
 ```
-
-
-## Technical consideration
-
-### Network and DNS
-
-Consider the following issues:
-
-- kube-apiserver runs on the host network of the kind container.
-- kube-apiserver cannot resolve a service name by kube-dns.
-- kube-apiserver cannot access a cluster IP.
-- kube-apiserver can access another container via the Docker network.
-- Chrome requires exactly match of domain name between Dex URL and a server certificate.
-
-Consequently,
-
-- kube-apiserver accesses Dex by resolving `/etc/hosts` and via the Docker network.
-- kubelogin and Chrome accesses Dex by resolving `/etc/hosts` and via the Docker network.
-
-### TLS server certificate
-
-Consider the following issues:
-
-- kube-apiserver requires `--oidc-issuer` is HTTPS URL.
-- kube-apiserver requires a CA certificate at startup, if `--oidc-ca-file` is given.
-- kube-apiserver mounts `/usr/local/share/ca-certificates` from the kind container.
-- It is possible to mount a file from the CI machine.
-- It is not possible to issue a certificate using Let's Encrypt in runtime.
-- Chrome requires a valid certificate in `~/.pki/nssdb`.
-
-As a result,
-
-- kube-apiserver uses the CA certificate of `/usr/local/share/ca-certificates/dex-ca.crt`. See the `extraMounts` section of [`cluster.yaml`](cluster.yaml).
-- kubelogin uses the CA certificate in `output/ca.crt`.
-- Chrome uses the CA certificate in `~/.pki/nssdb`.
-
-### Test environment
-
-- Set the issuer URL to kubectl. See [`kubeconfig_oidc.yaml`](kubeconfig_oidc.yaml).
-- Set the issuer URL to kube-apiserver. See [`cluster.yaml`](cluster.yaml).
-- Set `BROWSER` environment variable to run [`chromelogin`](chromelogin) by `xdg-open`.

acceptance_test/cluster.yaml

@@ -1,6 +1,5 @@
 kind: Cluster
 apiVersion: kind.x-k8s.io/v1alpha4
-# https://github.com/dexidp/dex/blob/master/Documentation/kubernetes.md
 kubeadmConfigPatches:
   - |
     apiVersion: kubeadm.k8s.io/v1beta2
@@ -9,12 +8,6 @@ kubeadmConfigPatches:
       name: config
     apiServer:
       extraArgs:
-        oidc-issuer-url: https://dex-server:10443/dex
-        oidc-client-id: YOUR_CLIENT_ID
+        oidc-issuer-url: OIDC_ISSUER_URL
+        oidc-client-id: OIDC_CLIENT_ID
         oidc-username-claim: email
-        oidc-ca-file: /usr/local/share/ca-certificates/dex-ca.crt
-nodes:
-  - role: control-plane
-    extraMounts:
-      - hostPath: /tmp/kubelogin-acceptance-test-dex-ca.crt
-        containerPath: /usr/local/share/ca-certificates/dex-ca.crt

acceptance_test/role.yaml

@@ -1,21 +0,0 @@
-apiVersion: rbac.authorization.k8s.io/v1
-kind: ClusterRole
-metadata:
-  name: readonly-all-resources
-rules:
-  - apiGroups: ["*"]
-    resources: ["*"]
-    verbs: ["get", "watch", "list"]
----
-apiVersion: rbac.authorization.k8s.io/v1
-kind: ClusterRoleBinding
-metadata:
-  name: readonly-all-resources
-subjects:
-  - kind: User
-    name: admin@example.com
-    apiGroup: rbac.authorization.k8s.io
-roleRef:
-  kind: ClusterRole
-  name: readonly-all-resources
-  apiGroup: rbac.authorization.k8s.io

dist/kubelogin.rb

@@ -1,15 +1,27 @@
 class Kubelogin < Formula
   desc "A kubectl plugin for Kubernetes OpenID Connect authentication"
   homepage "https://github.com/int128/kubelogin"
-  url "https://github.com/int128/kubelogin/releases/download/{{ env "VERSION" }}/kubelogin_darwin_amd64.zip"
+  baseurl = "https://github.com/int128/kubelogin/releases/download"
   version "{{ env "VERSION" }}"
-  sha256 "{{ sha256 .darwin_amd64_archive }}"
+  
+  if OS.mac?
+    kernel = "darwin"
+    sha256 "{{ sha256 .darwin_amd64_archive }}"
+  elsif OS.linux?
+    kernel = "linux"
+    sha256 "{{ sha256 .linux_amd64_archive }}"
+  end 
+   
+  url baseurl + "/#{version}/kubelogin_#{kernel}_amd64.zip"
+    
   def install
     bin.install "kubelogin" => "kubelogin"
     ln_s bin/"kubelogin", bin/"kubectl-oidc_login"
   end
+  
   test do
     system "#{bin}/kubelogin -h"
     system "#{bin}/kubectl-oidc_login -h"
   end
+    
 end

dist/oidc-login.yaml

@@ -22,8 +22,6 @@ spec:
 
   caveats: |
     You need to setup the OIDC provider, Kubernetes API server, role binding and kubeconfig.
-    See https://github.com/int128/kubelogin for more.
-
   version: {{ env "VERSION" }}
   platforms:
     - uri: https://github.com/int128/kubelogin/releases/download/{{ env "VERSION" }}/kubelogin_linux_amd64.zip
@@ -62,3 +60,27 @@ spec:
         matchLabels:
           os: windows
           arch: amd64
+    - uri: https://github.com/int128/kubelogin/releases/download/{{ env "VERSION" }}/kubelogin_linux_arm.zip
+      sha256: "{{ sha256 .linux_arm_archive }}"
+      bin: kubelogin
+      files:
+        - from: kubelogin
+          to: .
+        - from: LICENSE
+          to: .
+      selector:
+        matchLabels:
+          os: linux
+          arch: arm
+    - uri: https://github.com/int128/kubelogin/releases/download/{{ env "VERSION" }}/kubelogin_linux_arm64.zip
+      sha256: "{{ sha256 .linux_arm64_archive }}"
+      bin: kubelogin
+      files:
+        - from: kubelogin
+          to: .
+        - from: LICENSE
+          to: .
+      selector:
+        matchLabels:
+          os: linux
+          arch: arm64

docs/setup.md

@@ -126,6 +126,9 @@ Variable                | Value
 
 You do not need to set `YOUR_CLIENT_SECRET`.
 
+If you need `groups` claim for access control,
+see [jetstack/okta-kubectl-auth](https://github.com/jetstack/okta-kubectl-auth/blob/master/docs/okta-setup.md) and [#250](https://github.com/int128/kubelogin/issues/250).
+
 
 ## 2. Verify authentication
 
@@ -152,24 +155,9 @@ kubectl oidc-login setup --help
 ## 3. Bind a cluster role
 
 Here bind `cluster-admin` role to you.
-Apply the following manifest:
-
-```yaml
-kind: ClusterRoleBinding
-apiVersion: rbac.authorization.k8s.io/v1
-metadata:
-  name: oidc-cluster-admin
-roleRef:
-  apiGroup: rbac.authorization.k8s.io
-  kind: ClusterRole
-  name: cluster-admin
-subjects:
-- kind: User
-  name: ISSUER_URL#YOUR_SUBJECT
-```
 
 ```sh
-kubectl apply -f oidc-cluster-admin.yaml
+kubectl create clusterrolebinding oidc-cluster-admin --clusterrole=cluster-admin --user='ISSUER_URL#YOUR_SUBJECT'
 ```
 
 As well as you can create a custom cluster role and bind it.

docs/standalone-mode.md

@@ -99,31 +99,33 @@ Available Commands:
   version     Print the version information
 
 Flags:
-      --kubeconfig string                Path to the kubeconfig file
-      --context string                   The name of the kubeconfig context to use
-      --user string                      The name of the kubeconfig user to use. Prior to --context
-      --certificate-authority string     Path to a cert file for the certificate authority
-      --insecure-skip-tls-verify         If true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure
-      --grant-type string                The authorization grant type to use. One of (auto|authcode|authcode-keyboard|password) (default "auto")
-      --listen-address strings           Address to bind to the local server. If multiple addresses are given, it will try binding in order (default [127.0.0.1:8000,127.0.0.1:18000])
-      --listen-port ints                 (Deprecated: use --listen-address)
-      --skip-open-browser                If true, it does not open the browser on authentication
-      --username string                  If set, perform the resource owner password credentials grant
-      --password string                  If set, use the password instead of asking it
-      --add_dir_header                   If true, adds the file directory to the header
-      --alsologtostderr                  log to standard error as well as files
-      --log_backtrace_at traceLocation   when logging hits line file:N, emit a stack trace (default :0)
-      --log_dir string                   If non-empty, write log files in this directory
-      --log_file string                  If non-empty, use this log file
-      --log_file_max_size uint           Defines the maximum size a log file can grow to. Unit is megabytes. If the value is 0, the maximum file size is unlimited. (default 1800)
-      --logtostderr                      log to standard error instead of files (default true)
-      --skip_headers                     If true, avoid header prefixes in the log messages
-      --skip_log_headers                 If true, avoid headers when opening log files
-      --stderrthreshold severity         logs at or above this threshold go to stderr (default 2)
-  -v, --v Level                          number for the log level verbosity
-      --vmodule moduleSpec               comma-separated list of pattern=N settings for file-filtered logging
-  -h, --help                             help for main
-      --version                          version for main
+      --kubeconfig string                               Path to the kubeconfig file
+      --context string                                  The name of the kubeconfig context to use
+      --user string                                     The name of the kubeconfig user to use. Prior to --context
+      --certificate-authority string                    Path to a cert file for the certificate authority
+      --insecure-skip-tls-verify                        If true, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure
+      --grant-type string                               The authorization grant type to use. One of (auto|authcode|authcode-keyboard|password) (default "auto")
+      --listen-address strings                          Address to bind to the local server. If multiple addresses are given, it will try binding in order (default [127.0.0.1:8000,127.0.0.1:18000])
+      --listen-port ints                                (Deprecated: use --listen-address)
+      --skip-open-browser                               If true, it does not open the browser on authentication
+      --oidc-redirect-url-hostname string               Hostname of the redirect URL (default "localhost")
+      --oidc-auth-request-extra-params stringToString   Extra query parameters to send with an authentication request (default [])
+      --username string                                 If set, perform the resource owner password credentials grant
+      --password string                                 If set, use the password instead of asking it
+      --add_dir_header                                  If true, adds the file directory to the header
+      --alsologtostderr                                 log to standard error as well as files
+      --log_backtrace_at traceLocation                  when logging hits line file:N, emit a stack trace (default :0)
+      --log_dir string                                  If non-empty, write log files in this directory
+      --log_file string                                 If non-empty, use this log file
+      --log_file_max_size uint                          Defines the maximum size a log file can grow to. Unit is megabytes. If the value is 0, the maximum file size is unlimited. (default 1800)
+      --logtostderr                                     log to standard error instead of files (default true)
+      --skip_headers                                    If true, avoid header prefixes in the log messages
+      --skip_log_headers                                If true, avoid headers when opening log files
+      --stderrthreshold severity                        logs at or above this threshold go to stderr (default 2)
+  -v, --v Level                                         number for the log level verbosity
+      --vmodule moduleSpec                              comma-separated list of pattern=N settings for file-filtered logging
+  -h, --help                                            help for kubelogin
+      --version                                         version for kubelogin
 ```
 
 ### Kubeconfig

go.mod

@@ -7,20 +7,20 @@ require (
 	github.com/coreos/go-oidc v2.2.1+incompatible
 	github.com/dgrijalva/jwt-go v3.2.0+incompatible
 	github.com/golang/mock v1.4.3
-	github.com/google/go-cmp v0.4.0
+	github.com/google/go-cmp v0.5.0
 	github.com/google/wire v0.4.0
-	github.com/int128/oauth2cli v1.10.0
+	github.com/int128/oauth2cli v1.12.1
 	github.com/pkg/browser v0.0.0-20180916011732-0a3d74bf9ce4
 	github.com/pquerna/cachecontrol v0.0.0-20180517163645-1555304b9b35 // indirect
-	github.com/spf13/cobra v0.0.6
+	github.com/spf13/cobra v1.0.0
 	github.com/spf13/pflag v1.0.5
 	golang.org/x/crypto v0.0.0-20200220183623-bac4c82f6975
 	golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d
-	golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e
+	golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a
 	golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543
 	gopkg.in/square/go-jose.v2 v2.3.1 // indirect
-	gopkg.in/yaml.v2 v2.2.8
-	k8s.io/apimachinery v0.17.4
-	k8s.io/client-go v0.17.4
+	gopkg.in/yaml.v2 v2.3.0
+	k8s.io/apimachinery v0.18.5
+	k8s.io/client-go v0.18.5
 	k8s.io/klog v1.0.0
 )

go.sum

@@ -32,7 +32,6 @@ github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3Ee
 github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/cpuguy83/go-md2man/v2 v2.0.0/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
-github.com/davecgh/go-spew v0.0.0-20151105211317-5215b55f46b2/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -40,7 +39,7 @@ github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumC
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
 github.com/docker/spdystream v0.0.0-20160310174837-449fdfce4d96/go.mod h1:Qh8CwZgvJUkLughtfhJv5dyTYa91l1fOUCrgjqmcifM=
-github.com/elazarl/goproxy v0.0.0-20170405201442-c4fc26588b6e/go.mod h1:/Zj4wYkgs4iZTTu3o/KG3Itv/qCCa8VVMlb3i9OVuzc=
+github.com/elazarl/goproxy v0.0.0-20180725130230-947c36da3153/go.mod h1:/Zj4wYkgs4iZTTu3o/KG3Itv/qCCa8VVMlb3i9OVuzc=
 github.com/emicklei/go-restful v0.0.0-20170410110728-ff4f55a20633/go.mod h1:otzb+WCGbkyDHkqmQmT5YD2WR4BBwUdeQoFo8l/7tVs=
 github.com/evanphx/json-patch v4.2.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
@@ -63,8 +62,8 @@ github.com/gobwas/ws v1.0.2 h1:CoAavW/wd/kulfZmSIBt6p24n4j7tHgNVCjsfHVNUbo=
 github.com/gobwas/ws v1.0.2/go.mod h1:szmBTxLgaFppYjEmNtny/v3w89xOydFnnZMcgRRu/EM=
 github.com/gogo/protobuf v1.1.1/go.mod h1:r8qH/GZQm5c6nD/R0oafs1akxWv10x8SbQlK7atdtwQ=
 github.com/gogo/protobuf v1.2.1/go.mod h1:hp+jE20tsWTFYpLwKvXlhS1hjn+gTNwPg2I6zVXpSg4=
-github.com/gogo/protobuf v1.2.2-0.20190723190241-65acae22fc9d h1:3PaI8p3seN09VjbTYC/QWlUZdZ1qS1zGjy7LH2Wt07I=
-github.com/gogo/protobuf v1.2.2-0.20190723190241-65acae22fc9d/go.mod h1:SlYgWuQ5SjCEi6WLHjHCa1yvBfUnHcTbrrZtXPKa29o=
+github.com/gogo/protobuf v1.3.1 h1:DqDEcV5aeaTmdFBePNpYsp3FlcVH/2ISVVM9Qf8PSls=
+github.com/gogo/protobuf v1.3.1/go.mod h1:SlYgWuQ5SjCEi6WLHjHCa1yvBfUnHcTbrrZtXPKa29o=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/groupcache v0.0.0-20160516000752-02826c3e7903/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
 github.com/golang/groupcache v0.0.0-20190129154638-5b532d6fd5ef/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
@@ -83,11 +82,12 @@ github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
 github.com/google/go-cmp v0.3.0 h1:crn/baboCvb5fXaQ0IJ1SGTsTVrWpDsCWC8EGETZijY=
 github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
-github.com/google/go-cmp v0.4.0 h1:xsAVV57WRhGj6kEIi8ReJzQlHHqcBYCElAvkovg3B/4=
-github.com/google/go-cmp v0.4.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/gofuzz v0.0.0-20161122191042-44d81051d367/go.mod h1:HP5RmnzzSNb993RKQDq4+1A4ia9nllfqcQFTQJedwGI=
+github.com/google/go-cmp v0.5.0 h1:/QaMHBdZ26BB3SSst0Iwl10Epc+xhTquomWX0oZEB6w=
+github.com/google/go-cmp v0.5.0/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/gofuzz v1.0.0 h1:A8PeW59pxE9IoFRqBp37U+mSNaQoZ46F1f0f863XSXw=
 github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
+github.com/google/gofuzz v1.1.0 h1:Hsa8mG0dQ46ij8Sl2AYJDUv1oA9/d6Vk+3LG99Oe02g=
+github.com/google/gofuzz v1.1.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
 github.com/google/martian v2.1.0+incompatible/go.mod h1:9I4somxYTbIHy5NJKHRl3wXiIaQGbYVAs8BPL6v8lEs=
 github.com/google/pprof v0.0.0-20181206194817-3ea8567a2e57/go.mod h1:zfwlbNMJ+OItoe0UupaVj+oy1omPYYDuagoSzA8v9mc=
 github.com/google/subcommands v1.0.1/go.mod h1:ZjhPrFU+Olkh9WazFPsl27BQ4UPiG37m3yTrtFlrHVk=
@@ -96,6 +96,7 @@ github.com/google/wire v0.4.0 h1:kXcsA/rIGzJImVqPdhfnr6q0xsS9gU0515q1EPpJ9fE=
 github.com/google/wire v0.4.0/go.mod h1:ngWDr9Qvq3yZA10YrxfyGELY/AFWGVpy9c1LTRi1EoU=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gnostic v0.0.0-20170729233727-0c5108395e2d/go.mod h1:sJBsCZ4ayReDTBIg8b9dl28c5xFWyhBTVRp3pOg5EKY=
+github.com/googleapis/gnostic v0.1.0/go.mod h1:sJBsCZ4ayReDTBIg8b9dl28c5xFWyhBTVRp3pOg5EKY=
 github.com/gophercloud/gophercloud v0.1.0/go.mod h1:vxM41WHh5uqHVBMZHzuwNOHh8XEoIEcSTewFxm1c5g8=
 github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
 github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7/go.mod h1:FecbI9+v66THATjSRHfNgh1IVFe/9kFxbXtjV0ctIMA=
@@ -110,12 +111,12 @@ github.com/imdario/mergo v0.3.5 h1:JboBksRwiiAJWvIYJVo46AfV+IAIKZpfrSzVKj42R4Q=
 github.com/imdario/mergo v0.3.5/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJh5FfA=
 github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
-github.com/int128/listener v1.0.0 h1:a9H3m4jbXgXpxJUK3fxWrh37Iic/UU/kYOGE0WtjbbI=
-github.com/int128/listener v1.0.0/go.mod h1:sho0rrH7mNRRZH4hYOYx+xwRDGmtRndaUiu2z9iumes=
-github.com/int128/oauth2cli v1.10.0 h1:ypYxwjuBblyTRTdZTFQLgA08gYhVwsdlBEvuoNs6Xsw=
-github.com/int128/oauth2cli v1.10.0/go.mod h1:m5tJro14TyPDlIg+RIlGVnavkm1kTooROlcFlnhteVo=
+github.com/int128/listener v1.1.0 h1:2Jb41DWLpkQ3I9bIdBzO8H/tNwMvyl/OBZWtCV5Pjuw=
+github.com/int128/listener v1.1.0/go.mod h1:68WkmTN8PQtLzc9DucIaagAKeGVyMnyyKIkW4Xn47UA=
+github.com/int128/oauth2cli v1.12.1 h1:F+6sykVdM+0rede+jAJ2RICP3GAsLLGvPjSFLlI0U9Q=
+github.com/int128/oauth2cli v1.12.1/go.mod h1:0Wf2wAxKJNzbkPkUIYNhTjeLn/pqIBDOBAGfwrxGYQw=
 github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=
-github.com/json-iterator/go v0.0.0-20180612202835-f2b4162afba3/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
+github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
 github.com/json-iterator/go v1.1.8 h1:QiWkFLKq0T7mpzwOTu6BzNDbfTE8OLrYhVKYMLF46Ok=
 github.com/json-iterator/go v1.1.8/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
@@ -142,7 +143,6 @@ github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd h1:TRLaZ9cD/w8PVh93nsPXa1VrQ6jlwL5oN8l14QlcNfg=
 github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
-github.com/modern-go/reflect2 v0.0.0-20180320133207-05fbef0ca5da/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/modern-go/reflect2 v1.0.1 h1:9f412s+6RmYXLWZSEzVVgPGK7C2PphHj5RJrvfx9AWI=
 github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
@@ -152,7 +152,7 @@ github.com/mxk/go-flowrate v0.0.0-20140419014527-cca7078d478f/go.mod h1:ZdcZmHo+
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=
 github.com/onsi/ginkgo v0.0.0-20170829012221-11459a886d9c/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
-github.com/onsi/ginkgo v1.10.1/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
+github.com/onsi/ginkgo v1.11.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/gomega v0.0.0-20170829124025-dcabb60a477c/go.mod h1:C1qb7wdrVGGVU+Z6iS04AVkA3Q65CEZX59MT0QO5uiA=
 github.com/onsi/gomega v1.7.0/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
@@ -160,7 +160,6 @@ github.com/peterbourgon/diskv v2.0.1+incompatible/go.mod h1:uqqh8zWWbv1HBMNONnaR
 github.com/pkg/browser v0.0.0-20180916011732-0a3d74bf9ce4 h1:49lOXmGaUpV9Fz3gd7TFZY106KVlPVa5jcYD1gaQf98=
 github.com/pkg/browser v0.0.0-20180916011732-0a3d74bf9ce4/go.mod h1:4OwLy04Bl9Ef3GJJCoec+30X3LQs/0/m4HFRt/2LUSA=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
-github.com/pmezard/go-difflib v0.0.0-20151028094244-d8ed2627bdf0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pquerna/cachecontrol v0.0.0-20180517163645-1555304b9b35 h1:J9b7z+QKAmPf4YLrFg6oQUotqHQeUNWwkvo7jZp1GLU=
@@ -183,8 +182,8 @@ github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasO
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
 github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTdifk=
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
-github.com/spf13/cobra v0.0.6 h1:breEStsVwemnKh2/s6gMvSdMEkwW0sK8vGStnlVBMCs=
-github.com/spf13/cobra v0.0.6/go.mod h1:/6GTrnGXV9HjY+aR4k0oJ5tcvakLuG6EuKReYlHNrgE=
+github.com/spf13/cobra v1.0.0 h1:6m/oheQuQ13N9ks4hubMG6BnvwOeaJrqSPLahSnczz8=
+github.com/spf13/cobra v1.0.0/go.mod h1:/6GTrnGXV9HjY+aR4k0oJ5tcvakLuG6EuKReYlHNrgE=
 github.com/spf13/jwalterweatherman v1.0.0/go.mod h1:cQK4TGJAtQXfYWX+Ddv3mKDzgVb68N+wFjFa4jdeBTo=
 github.com/spf13/pflag v0.0.0-20170130214245-9ff6c6923cff/go.mod h1:DYY7MBk1bdzusC3SYhjObp+wFpr4gzcvqqNjLnInEg4=
 github.com/spf13/pflag v1.0.3 h1:zPAT6CGy6wXeQ7NtTnaTerfKOsV6V6F8agHXFiazDkg=
@@ -194,7 +193,6 @@ github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An
 github.com/spf13/viper v1.4.0/go.mod h1:PTJ7Z/lr49W6bUbkmS1V3by4uWynFiR9p7+dSq/yZzE=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v0.0.0-20151208002404-e3a8ff8ce365/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
@@ -247,8 +245,8 @@ golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20190227155943-e225da77a7e6/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58 h1:8gQV6CLnAEikrhgkHFbMAEhagSSnXWGV915qUMm9mrU=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e h1:vcxGaoTs7kV8m5Np9uUNQin4BrLOthgV7252N8V+FwY=
-golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a h1:WXEvlFVvvGxCJLG6REjsT03iWnKLEWinaScsxF2Vm2o=
+golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20170830134202-bb24a47a89ea/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -258,8 +256,7 @@ golang.org/x/sys v0.0.0-20181116152217-5ac8a444bdc5/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20190209173611-3b5209105503/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190826190057-c7b8b68b1456 h1:ng0gs1AKnRRuEMZoTLLlbOd+C17zUDepwGQBb/n+JVg=
-golang.org/x/sys v0.0.0-20190826190057-c7b8b68b1456/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191022100944-742c48ecaeb7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42 h1:vEOn+mP2zCOVzKckCZy6YsCtDblrpj/w7B9nxGNELpg=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.0.0-20160726164857-2910a502d2bf/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -281,8 +278,6 @@ golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3
 golang.org/x/tools v0.0.0-20190312170243-e65039ee4138/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 golang.org/x/tools v0.0.0-20190422233926-fe54fb35175b/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 golang.org/x/tools v0.0.0-20190425150028-36563e24a262/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7 h1:9zdDQZ7Thm29KFXgAX/+yaf3eVbP7djjWp/dXAppNCc=
-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/api v0.4.0/go.mod h1:8k5glujaEP+g9n7WNsDg8QP6cUVNI86fCNMcbazEtwE=
@@ -314,26 +309,32 @@ gopkg.in/yaml.v2 v2.2.2 h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
+gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190106161140-3f1c8253044a/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
-k8s.io/api v0.17.4 h1:HbwOhDapkguO8lTAE8OX3hdF2qp8GtpC9CW/MQATXXo=
-k8s.io/api v0.17.4/go.mod h1:5qxx6vjmwUVG2nHQTKGlLts8Tbok8PzHl4vHtVFuZCA=
-k8s.io/apimachinery v0.17.4 h1:UzM+38cPUJnzqSQ+E1PY4YxMHIzQyCg29LOoGfo79Zw=
-k8s.io/apimachinery v0.17.4/go.mod h1:gxLnyZcGNdZTCLnq3fgzyg2A5BVCHTNDFrw8AmuJ+0g=
-k8s.io/client-go v0.17.4 h1:VVdVbpTY70jiNHS1eiFkUt7ZIJX3txd29nDxxXH4en8=
-k8s.io/client-go v0.17.4/go.mod h1:ouF6o5pz3is8qU0/qYL2RnoxOPqgfuidYLowytyLJmc=
+k8s.io/api v0.18.5 h1:fKbCxr+U3fu7k6jB+QeYPD/c6xKYeSJ2KVWmyUypuWM=
+k8s.io/api v0.18.5/go.mod h1:tN+e/2nbdGKOAH55NMV8oGrMG+3uRlA9GaRfvnCCSNk=
+k8s.io/apimachinery v0.18.5 h1:Lh6tgsM9FMkC12K5T5QjRm7rDs6aQN5JHkA0JomULDM=
+k8s.io/apimachinery v0.18.5/go.mod h1:OaXp26zu/5J7p0f92ASynJa1pZo06YlV9fG7BoWbCko=
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 k8s.io/gengo v0.0.0-20190128074634-0689ccc1d7d6/go.mod h1:ezvh/TsK7cY6rbqRK0oQQ8IAqLxYwwyPxAX1Pzy0ii0=
 k8s.io/klog v0.0.0-20181102134211-b9b56d5dfc92/go.mod h1:Gq+BEi5rUBO/HRz0bTSXDUcqjScdoY3a9IHpCEIOOfk=
 k8s.io/klog v0.3.0/go.mod h1:Gq+BEi5rUBO/HRz0bTSXDUcqjScdoY3a9IHpCEIOOfk=
 k8s.io/klog v1.0.0 h1:Pt+yjF5aB1xDSVbau4VsWe+dQNzA0qv1LlXdC2dF6Q8=
 k8s.io/klog v1.0.0/go.mod h1:4Bi6QPql/J/LkTDqv7R/cd3hPo4k2DG6Ptcz060Ez5I=
-k8s.io/kube-openapi v0.0.0-20191107075043-30be4d16710a/go.mod h1:1TqjTSzOxsLGIKfj0lK8EeCP7K1iUG65v09OM0/WG5E=
-k8s.io/utils v0.0.0-20191114184206-e782cd3c129f h1:GiPwtSzdP43eI1hpPCbROQCCIgCuiMMNF8YUVLF3vJo=
-k8s.io/utils v0.0.0-20191114184206-e782cd3c129f/go.mod h1:sZAwmy6armz5eXlNoLmJcl4F1QuKu7sr+mFQ0byX7Ew=
+k8s.io/kube-openapi v0.0.0-20200410145947-61e04a5be9a6/go.mod h1:GRQhZsXIAJ1xR0C9bd8UpWHZ5plfAS9fzPjJuQ6JL3E=
+k8s.io/utils v0.0.0-20200324210504-a9aa75ae1b89 h1:d4vVOjXm687F1iLSP2q3lyPPuyvTUt3aVoBpi2DqRsU=
+k8s.io/utils v0.0.0-20200324210504-a9aa75ae1b89/go.mod h1:sZAwmy6armz5eXlNoLmJcl4F1QuKu7sr+mFQ0byX7Ew=
 rsc.io/quote/v3 v3.1.0 h1:9JKUTTIUgS6kzR9mK1YuGKv6Nl+DijDNIc0ghT58FaY=
 rsc.io/quote/v3 v3.1.0/go.mod h1:yEA65RcK8LyAZtP9Kv3t0HmxON59tX3rD+tICJqUlj0=
 rsc.io/sampler v1.3.0 h1:7uVkIFmeBqHfdjD+gZwtXXI+RODJ2Wc4O7MPEh/QiW4=
 rsc.io/sampler v1.3.0/go.mod h1:T1hPZKmBbMNahiBKFy5HrXp6adAjACjK9JXDnKaTXpA=
-sigs.k8s.io/structured-merge-diff v0.0.0-20190525122527-15d366b2352e/go.mod h1:wWxsB5ozmmv/SG7nM11ayaAW51xMvak/t1r0CSlcokI=
+sigs.k8s.io/structured-merge-diff/v3 v3.0.0-20200116222232-67a7b8c61874/go.mod h1:PlARxl6Hbt/+BC80dRLi1qAmnMqwqDg62YvvVkZjemw=
+sigs.k8s.io/structured-merge-diff/v3 v3.0.0 h1:dOmIZBMfhcHS09XZkMyUgkq5trg3/jRyJYFZUiaOp8E=
+sigs.k8s.io/structured-merge-diff/v3 v3.0.0/go.mod h1:PlARxl6Hbt/+BC80dRLi1qAmnMqwqDg62YvvVkZjemw=
 sigs.k8s.io/yaml v1.1.0 h1:4A07+ZFc2wgJwo8YNlQpr1rVlgUDlxXHhPJciaPY5gs=
 sigs.k8s.io/yaml v1.1.0/go.mod h1:UJmg0vDUVViEyp3mgSv9WPwZCDxu4rQW1olrI1uml+o=
+sigs.k8s.io/yaml v1.2.0 h1:kr/MCeFWJWTwyaHoR9c8EjH9OumOmoF9YGiZd7lFm/Q=
+sigs.k8s.io/yaml v1.2.0/go.mod h1:yfXDCHCao9+ENCvLSE62v9VSji2MKu5jeNfTrofGhJc=

integration_test/credetial_plugin_test.go

@@ -1,26 +1,25 @@
 package integration_test
 
 import (
+	"bytes"
 	"context"
+	"encoding/json"
+	"io"
 	"io/ioutil"
 	"os"
 	"testing"
 	"time"
 
-	"github.com/golang/mock/gomock"
 	"github.com/google/go-cmp/cmp"
-	"github.com/int128/kubelogin/integration_test/idp"
-	"github.com/int128/kubelogin/integration_test/idp/mock_idp"
-	"github.com/int128/kubelogin/integration_test/keys"
-	"github.com/int128/kubelogin/integration_test/localserver"
+	"github.com/int128/kubelogin/integration_test/httpdriver"
+	"github.com/int128/kubelogin/integration_test/keypair"
+	"github.com/int128/kubelogin/integration_test/oidcserver"
 	"github.com/int128/kubelogin/pkg/adaptors/browser"
-	"github.com/int128/kubelogin/pkg/adaptors/browser/mock_browser"
-	"github.com/int128/kubelogin/pkg/adaptors/credentialpluginwriter"
-	"github.com/int128/kubelogin/pkg/adaptors/credentialpluginwriter/mock_credentialpluginwriter"
-	"github.com/int128/kubelogin/pkg/adaptors/tokencache"
 	"github.com/int128/kubelogin/pkg/di"
-	"github.com/int128/kubelogin/pkg/testing/jwt"
+	"github.com/int128/kubelogin/pkg/testing/clock"
 	"github.com/int128/kubelogin/pkg/testing/logger"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	clientauthenticationv1beta1 "k8s.io/client-go/pkg/apis/clientauthentication/v1beta1"
 )
 
 // Run the integration tests of the credential plugin use-case.
@@ -31,6 +30,8 @@ import (
 // 4. Verify the output.
 //
 func TestCredentialPlugin(t *testing.T) {
+	timeout := 3 * time.Second
+	now := time.Date(2020, 1, 1, 0, 0, 0, 0, time.UTC)
 	tokenCacheDir, err := ioutil.TempDir("", "kube")
 	if err != nil {
 		t.Fatalf("could not create a cache dir: %s", err)
@@ -41,307 +42,348 @@ func TestCredentialPlugin(t *testing.T) {
 		}
 	}()
 
-	t.Run("NoTLS", func(t *testing.T) {
-		testCredentialPlugin(t, credentialPluginTestCase{
-			TokenCacheDir: tokenCacheDir,
-			Keys:          keys.None,
-			ExtraArgs: []string{
-				"--token-cache-dir", tokenCacheDir,
+	for name, tc := range map[string]struct {
+		keyPair keypair.KeyPair
+		args    []string
+	}{
+		"NoTLS": {},
+		"TLS": {
+			keyPair: keypair.Server,
+			args:    []string{"--certificate-authority", keypair.Server.CACertPath},
+		},
+	} {
+		t.Run(name, func(t *testing.T) {
+			t.Run("AuthCode", func(t *testing.T) {
+				t.Parallel()
+				ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+				defer cancel()
+				sv := oidcserver.New(t, tc.keyPair, oidcserver.Config{
+					Want: oidcserver.Want{
+						Scope:             "openid",
+						RedirectURIPrefix: "http://localhost:",
+					},
+					Response: oidcserver.Response{
+						IDTokenExpiry: now.Add(time.Hour),
+					},
+				})
+				defer sv.Shutdown(t, ctx)
+				var stdout bytes.Buffer
+				runGetToken(t, ctx, getTokenConfig{
+					tokenCacheDir: tokenCacheDir,
+					issuerURL:     sv.IssuerURL(),
+					httpDriver:    httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+					now:           now,
+					stdout:        &stdout,
+					args:          tc.args,
+				})
+				assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
+			})
+
+			t.Run("ROPC", func(t *testing.T) {
+				t.Parallel()
+				ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+				defer cancel()
+				sv := oidcserver.New(t, tc.keyPair, oidcserver.Config{
+					Want: oidcserver.Want{
+						Scope:             "openid",
+						RedirectURIPrefix: "http://localhost:",
+						Username:          "USER1",
+						Password:          "PASS1",
+					},
+					Response: oidcserver.Response{
+						IDTokenExpiry: now.Add(time.Hour),
+					},
+				})
+				defer sv.Shutdown(t, ctx)
+				var stdout bytes.Buffer
+				runGetToken(t, ctx, getTokenConfig{
+					tokenCacheDir: tokenCacheDir,
+					issuerURL:     sv.IssuerURL(),
+					httpDriver:    httpdriver.Zero(t),
+					now:           now,
+					stdout:        &stdout,
+					args: append([]string{
+						"--username", "USER1",
+						"--password", "PASS1",
+					}, tc.args...),
+				})
+				assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
+			})
+
+			t.Run("TokenCacheLifecycle", func(t *testing.T) {
+				t.Parallel()
+				ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+				defer cancel()
+				sv := oidcserver.New(t, tc.keyPair, oidcserver.Config{})
+				defer sv.Shutdown(t, ctx)
+
+				t.Run("NoCache", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{
+						Want: oidcserver.Want{
+							Scope:             "openid",
+							RedirectURIPrefix: "http://localhost:",
+						},
+						Response: oidcserver.Response{
+							IDTokenExpiry: now.Add(time.Hour),
+							RefreshToken:  "REFRESH_TOKEN_1",
+						},
+					})
+					var stdout bytes.Buffer
+					runGetToken(t, ctx, getTokenConfig{
+						tokenCacheDir: tokenCacheDir,
+						issuerURL:     sv.IssuerURL(),
+						httpDriver:    httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+						now:           now,
+						stdout:        &stdout,
+						args:          tc.args,
+					})
+					assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
+				})
+				t.Run("Valid", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{})
+					var stdout bytes.Buffer
+					runGetToken(t, ctx, getTokenConfig{
+						tokenCacheDir: tokenCacheDir,
+						issuerURL:     sv.IssuerURL(),
+						httpDriver:    httpdriver.Zero(t),
+						now:           now,
+						stdout:        &stdout,
+						args:          tc.args,
+					})
+					assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
+				})
+				t.Run("Refresh", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{
+						Want: oidcserver.Want{
+							Scope:             "openid",
+							RedirectURIPrefix: "http://localhost:",
+							RefreshToken:      "REFRESH_TOKEN_1",
+						},
+						Response: oidcserver.Response{
+							IDTokenExpiry: now.Add(3 * time.Hour),
+							RefreshToken:  "REFRESH_TOKEN_2",
+						},
+					})
+					var stdout bytes.Buffer
+					runGetToken(t, ctx, getTokenConfig{
+						tokenCacheDir: tokenCacheDir,
+						issuerURL:     sv.IssuerURL(),
+						httpDriver:    httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+						now:           now.Add(2 * time.Hour),
+						stdout:        &stdout,
+						args:          tc.args,
+					})
+					assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(3*time.Hour))
+				})
+				t.Run("RefreshAgain", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{
+						Want: oidcserver.Want{
+							Scope:             "openid",
+							RedirectURIPrefix: "http://localhost:",
+							RefreshToken:      "REFRESH_TOKEN_2",
+						},
+						Response: oidcserver.Response{
+							IDTokenExpiry: now.Add(5 * time.Hour),
+						},
+					})
+					var stdout bytes.Buffer
+					runGetToken(t, ctx, getTokenConfig{
+						tokenCacheDir: tokenCacheDir,
+						issuerURL:     sv.IssuerURL(),
+						httpDriver:    httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+						now:           now.Add(4 * time.Hour),
+						stdout:        &stdout,
+						args:          tc.args,
+					})
+					assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(5*time.Hour))
+				})
+			})
+		})
+	}
+
+	t.Run("PKCE", func(t *testing.T) {
+		t.Parallel()
+		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+		defer cancel()
+		sv := oidcserver.New(t, keypair.None, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:               "openid",
+				RedirectURIPrefix:   "http://localhost:",
+				CodeChallengeMethod: "S256",
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry:                 now.Add(time.Hour),
+				CodeChallengeMethodsSupported: []string{"plain", "S256"},
 			},
 		})
-	})
-	t.Run("TLS", func(t *testing.T) {
-		t.Run("CertFile", func(t *testing.T) {
-			testCredentialPlugin(t, credentialPluginTestCase{
-				TokenCacheDir: tokenCacheDir,
-				TokenCacheKey: tokencache.Key{CACertFilename: keys.Server.CACertPath},
-				Keys:          keys.Server,
-				ExtraArgs: []string{
-					"--token-cache-dir", tokenCacheDir,
-					"--certificate-authority", keys.Server.CACertPath,
-				},
-			})
-		})
-		t.Run("CertData", func(t *testing.T) {
-			testCredentialPlugin(t, credentialPluginTestCase{
-				TokenCacheDir: tokenCacheDir,
-				TokenCacheKey: tokencache.Key{CACertData: keys.Server.CACertBase64},
-				Keys:          keys.Server,
-				ExtraArgs: []string{
-					"--token-cache-dir", tokenCacheDir,
-					"--certificate-authority-data", keys.Server.CACertBase64,
-				},
-			})
+		defer sv.Shutdown(t, ctx)
+		var stdout bytes.Buffer
+		runGetToken(t, ctx, getTokenConfig{
+			tokenCacheDir: tokenCacheDir,
+			issuerURL:     sv.IssuerURL(),
+			httpDriver:    httpdriver.New(ctx, t, nil),
+			now:           now,
+			stdout:        &stdout,
 		})
+		assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
 	})
-}
 
-type credentialPluginTestCase struct {
-	TokenCacheDir string
-	TokenCacheKey tokencache.Key
-	Keys          keys.Keys
-	ExtraArgs     []string
-}
-
-func testCredentialPlugin(t *testing.T, tc credentialPluginTestCase) {
-	timeout := 1 * time.Second
-
-	t.Run("Defaults", func(t *testing.T) {
+	t.Run("TLSData", func(t *testing.T) {
 		t.Parallel()
 		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
 		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), tc.Keys)
-		defer server.Shutdown(t, ctx)
-		var idToken string
-		setupAuthCodeFlow(t, provider, serverURL, "openid", nil, &idToken)
-		writerMock := newCredentialPluginWriterMock(t, ctrl, &idToken)
-		browserMock := newBrowserMock(ctx, t, ctrl, tc.Keys)
-
-		args := []string{
-			"--oidc-issuer-url", serverURL,
-			"--oidc-client-id", "kubernetes",
-		}
-		args = append(args, tc.ExtraArgs...)
-		runGetTokenCmd(t, ctx, browserMock, writerMock, args)
-	})
-
-	t.Run("ResourceOwnerPasswordCredentials", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), tc.Keys)
-		defer server.Shutdown(t, ctx)
-		idToken := newIDToken(t, serverURL, "", tokenExpiryFuture)
-		setupROPCFlow(provider, serverURL, "openid", "USER", "PASS", idToken)
-		writerMock := newCredentialPluginWriterMock(t, ctrl, &idToken)
-		browserMock := mock_browser.NewMockInterface(ctrl)
-
-		args := []string{
-			"--oidc-issuer-url", serverURL,
-			"--oidc-client-id", "kubernetes",
-			"--username", "USER",
-			"--password", "PASS",
-		}
-		args = append(args, tc.ExtraArgs...)
-		runGetTokenCmd(t, ctx, browserMock, writerMock, args)
-	})
-
-	t.Run("HasValidToken", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), tc.Keys)
-		defer server.Shutdown(t, ctx)
-		idToken := newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryFuture)
-		writerMock := newCredentialPluginWriterMock(t, ctrl, &idToken)
-		browserMock := mock_browser.NewMockInterface(ctrl)
-		setupTokenCache(t, tc, serverURL, tokencache.Value{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
+		sv := oidcserver.New(t, keypair.Server, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:             "openid",
+				RedirectURIPrefix: "http://localhost:",
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry: now.Add(time.Hour),
+			},
 		})
-
-		args := []string{
-			"--oidc-issuer-url", serverURL,
-			"--oidc-client-id", "kubernetes",
-		}
-		args = append(args, tc.ExtraArgs...)
-		runGetTokenCmd(t, ctx, browserMock, writerMock, args)
-		assertTokenCache(t, tc, serverURL, tokencache.Value{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
-		})
-	})
-
-	t.Run("HasValidRefreshToken", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), tc.Keys)
-		defer server.Shutdown(t, ctx)
-		validIDToken := newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryFuture)
-		expiredIDToken := newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryPast)
-
-		provider.EXPECT().Discovery().Return(idp.NewDiscoveryResponse(serverURL))
-		provider.EXPECT().GetCertificates().Return(idp.NewCertificatesResponse(jwt.PrivateKey))
-		provider.EXPECT().Refresh("VALID_REFRESH_TOKEN").
-			Return(idp.NewTokenResponse(validIDToken, "NEW_REFRESH_TOKEN"), nil)
-
-		setupTokenCache(t, tc, serverURL, tokencache.Value{
-			IDToken:      expiredIDToken,
-			RefreshToken: "VALID_REFRESH_TOKEN",
-		})
-		writerMock := newCredentialPluginWriterMock(t, ctrl, &validIDToken)
-		browserMock := mock_browser.NewMockInterface(ctrl)
-
-		args := []string{
-			"--oidc-issuer-url", serverURL,
-			"--oidc-client-id", "kubernetes",
-		}
-		args = append(args, tc.ExtraArgs...)
-		runGetTokenCmd(t, ctx, browserMock, writerMock, args)
-		assertTokenCache(t, tc, serverURL, tokencache.Value{
-			IDToken:      validIDToken,
-			RefreshToken: "NEW_REFRESH_TOKEN",
-		})
-	})
-
-	t.Run("HasExpiredRefreshToken", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), tc.Keys)
-		defer server.Shutdown(t, ctx)
-		validIDToken := newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryFuture)
-		expiredIDToken := newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryPast)
-
-		setupAuthCodeFlow(t, provider, serverURL, "openid", nil, &validIDToken)
-		provider.EXPECT().Refresh("EXPIRED_REFRESH_TOKEN").
-			Return(nil, &idp.ErrorResponse{Code: "invalid_request", Description: "token has expired"}).
-			MaxTimes(2) // package oauth2 will retry refreshing the token
-
-		setupTokenCache(t, tc, serverURL, tokencache.Value{
-			IDToken:      expiredIDToken,
-			RefreshToken: "EXPIRED_REFRESH_TOKEN",
-		})
-		writerMock := newCredentialPluginWriterMock(t, ctrl, &validIDToken)
-		browserMock := newBrowserMock(ctx, t, ctrl, tc.Keys)
-
-		args := []string{
-			"--oidc-issuer-url", serverURL,
-			"--oidc-client-id", "kubernetes",
-		}
-		args = append(args, tc.ExtraArgs...)
-		runGetTokenCmd(t, ctx, browserMock, writerMock, args)
-		assertTokenCache(t, tc, serverURL, tokencache.Value{
-			IDToken:      validIDToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
+		defer sv.Shutdown(t, ctx)
+		var stdout bytes.Buffer
+		runGetToken(t, ctx, getTokenConfig{
+			tokenCacheDir: tokenCacheDir,
+			issuerURL:     sv.IssuerURL(),
+			httpDriver:    httpdriver.New(ctx, t, keypair.Server.TLSConfig),
+			now:           now,
+			stdout:        &stdout,
+			args:          []string{"--certificate-authority-data", keypair.Server.CACertBase64},
 		})
+		assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
 	})
 
 	t.Run("ExtraScopes", func(t *testing.T) {
 		t.Parallel()
 		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
 		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
+		sv := oidcserver.New(t, keypair.None, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:             "email profile openid",
+				RedirectURIPrefix: "http://localhost:",
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry: now.Add(time.Hour),
+			},
+		})
+		defer sv.Shutdown(t, ctx)
+		var stdout bytes.Buffer
+		runGetToken(t, ctx, getTokenConfig{
+			tokenCacheDir: tokenCacheDir,
+			issuerURL:     sv.IssuerURL(),
+			httpDriver:    httpdriver.New(ctx, t, nil),
+			now:           now,
+			stdout:        &stdout,
+			args: []string{
+				"--oidc-extra-scope", "email",
+				"--oidc-extra-scope", "profile",
+			},
+		})
+		assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
+	})
 
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), tc.Keys)
-		defer server.Shutdown(t, ctx)
-		var idToken string
-		setupAuthCodeFlow(t, provider, serverURL, "email profile openid", nil, &idToken)
-		writerMock := newCredentialPluginWriterMock(t, ctrl, &idToken)
-		browserMock := newBrowserMock(ctx, t, ctrl, tc.Keys)
-
-		args := []string{
-			"--oidc-issuer-url", serverURL,
-			"--oidc-client-id", "kubernetes",
-			"--oidc-extra-scope", "email",
-			"--oidc-extra-scope", "profile",
-		}
-		args = append(args, tc.ExtraArgs...)
-		runGetTokenCmd(t, ctx, browserMock, writerMock, args)
+	t.Run("RedirectURLHostname", func(t *testing.T) {
+		t.Parallel()
+		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+		defer cancel()
+		sv := oidcserver.New(t, keypair.None, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:             "openid",
+				RedirectURIPrefix: "http://127.0.0.1:",
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry: now.Add(time.Hour),
+			},
+		})
+		defer sv.Shutdown(t, ctx)
+		var stdout bytes.Buffer
+		runGetToken(t, ctx, getTokenConfig{
+			tokenCacheDir: tokenCacheDir,
+			issuerURL:     sv.IssuerURL(),
+			httpDriver:    httpdriver.New(ctx, t, nil),
+			now:           now,
+			stdout:        &stdout,
+			args:          []string{"--oidc-redirect-url-hostname", "127.0.0.1"},
+		})
+		assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
 	})
 
 	t.Run("ExtraParams", func(t *testing.T) {
 		t.Parallel()
 		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
 		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), tc.Keys)
-		defer server.Shutdown(t, ctx)
-		var idToken string
-		setupAuthCodeFlow(t, provider, serverURL, "openid", map[string]string{
-			"ttl":    "86400",
-			"reauth": "false",
-		}, &idToken)
-		writerMock := newCredentialPluginWriterMock(t, ctrl, &idToken)
-		browserMock := newBrowserMock(ctx, t, ctrl, tc.Keys)
-
-		args := []string{
-			"--oidc-issuer-url", serverURL,
-			"--oidc-client-id", "kubernetes",
-			"--oidc-auth-request-extra-params", "ttl=86400",
-			"--oidc-auth-request-extra-params", "reauth=false",
-		}
-		args = append(args, tc.ExtraArgs...)
-		runGetTokenCmd(t, ctx, browserMock, writerMock, args)
+		sv := oidcserver.New(t, keypair.None, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:             "openid",
+				RedirectURIPrefix: "http://localhost:",
+				ExtraParams: map[string]string{
+					"ttl":    "86400",
+					"reauth": "false",
+				},
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry: now.Add(time.Hour),
+			},
+		})
+		defer sv.Shutdown(t, ctx)
+		var stdout bytes.Buffer
+		runGetToken(t, ctx, getTokenConfig{
+			tokenCacheDir: tokenCacheDir,
+			issuerURL:     sv.IssuerURL(),
+			httpDriver:    httpdriver.New(ctx, t, nil),
+			now:           now,
+			stdout:        &stdout,
+			args: []string{
+				"--oidc-auth-request-extra-params", "ttl=86400",
+				"--oidc-auth-request-extra-params", "reauth=false",
+			},
+		})
+		assertCredentialPluginStdout(t, &stdout, sv.LastTokenResponse().IDToken, now.Add(time.Hour))
 	})
 }
 
-func newCredentialPluginWriterMock(t *testing.T, ctrl *gomock.Controller, idToken *string) *mock_credentialpluginwriter.MockInterface {
-	writer := mock_credentialpluginwriter.NewMockInterface(ctrl)
-	writer.EXPECT().
-		Write(gomock.Any()).
-		Do(func(got credentialpluginwriter.Output) {
-			want := credentialpluginwriter.Output{
-				Token:  *idToken,
-				Expiry: tokenExpiryFuture,
-			}
-			if diff := cmp.Diff(want, got); diff != "" {
-				t.Errorf("mismatch (-want +got):\n%s", diff)
-			}
-		})
-	return writer
+type getTokenConfig struct {
+	tokenCacheDir string
+	issuerURL     string
+	httpDriver    browser.Interface
+	stdout        io.Writer
+	now           time.Time
+	args          []string
 }
 
-func runGetTokenCmd(t *testing.T, ctx context.Context, b browser.Interface, w credentialpluginwriter.Interface, args []string) {
-	t.Helper()
-	cmd := di.NewCmdForHeadless(logger.New(t), b, w)
+func runGetToken(t *testing.T, ctx context.Context, cfg getTokenConfig) {
+	cmd := di.NewCmdForHeadless(clock.Fake(cfg.now), os.Stdin, cfg.stdout, logger.New(t), cfg.httpDriver)
 	exitCode := cmd.Run(ctx, append([]string{
-		"kubelogin", "get-token",
-		"--v=1",
+		"kubelogin",
+		"get-token",
+		"--token-cache-dir", cfg.tokenCacheDir,
+		"--oidc-issuer-url", cfg.issuerURL,
+		"--oidc-client-id", "kubernetes",
 		"--listen-address", "127.0.0.1:0",
-	}, args...), "HEAD")
+	}, cfg.args...), "latest")
 	if exitCode != 0 {
 		t.Errorf("exit status wants 0 but %d", exitCode)
 	}
 }
 
-func setupTokenCache(t *testing.T, tc credentialPluginTestCase, serverURL string, v tokencache.Value) {
-	k := tc.TokenCacheKey
-	k.IssuerURL = serverURL
-	k.ClientID = "kubernetes"
-	var r tokencache.Repository
-	err := r.Save(tc.TokenCacheDir, k, v)
-	if err != nil {
-		t.Errorf("could not set up the token cache: %s", err)
-	}
-}
-
-func assertTokenCache(t *testing.T, tc credentialPluginTestCase, serverURL string, want tokencache.Value) {
-	k := tc.TokenCacheKey
-	k.IssuerURL = serverURL
-	k.ClientID = "kubernetes"
-	var r tokencache.Repository
-	got, err := r.FindByKey(tc.TokenCacheDir, k)
-	if err != nil {
-		t.Errorf("could not set up the token cache: %s", err)
-	}
-	if diff := cmp.Diff(&want, got); diff != "" {
-		t.Errorf("mismatch (-want +got):\n%s", diff)
+func assertCredentialPluginStdout(t *testing.T, stdout io.Reader, token string, expiry time.Time) {
+	var got clientauthenticationv1beta1.ExecCredential
+	if err := json.NewDecoder(stdout).Decode(&got); err != nil {
+		t.Errorf("could not decode json of the credential plugin: %s", err)
+		return
+	}
+	want := clientauthenticationv1beta1.ExecCredential{
+		TypeMeta: metav1.TypeMeta{
+			APIVersion: "client.authentication.k8s.io/v1beta1",
+			Kind:       "ExecCredential",
+		},
+		Status: &clientauthenticationv1beta1.ExecCredentialStatus{
+			Token:               token,
+			ExpirationTimestamp: &metav1.Time{Time: expiry},
+		},
+	}
+	if diff := cmp.Diff(want, got); diff != "" {
+		t.Errorf("kubeconfig mismatch (-want +got):\n%s", diff)
 	}
 }

integration_test/helpers_test.go

@@ -1,91 +0,0 @@
-package integration_test
-
-import (
-	"context"
-	"net/http"
-	"testing"
-	"time"
-
-	"github.com/golang/mock/gomock"
-	"github.com/int128/kubelogin/integration_test/idp"
-	"github.com/int128/kubelogin/integration_test/idp/mock_idp"
-	"github.com/int128/kubelogin/integration_test/keys"
-	"github.com/int128/kubelogin/pkg/adaptors/browser"
-	"github.com/int128/kubelogin/pkg/adaptors/browser/mock_browser"
-	"github.com/int128/kubelogin/pkg/testing/jwt"
-)
-
-var (
-	tokenExpiryFuture = time.Now().Add(time.Hour).Round(time.Second)
-	tokenExpiryPast   = time.Now().Add(-time.Hour).Round(time.Second)
-)
-
-func newIDToken(t *testing.T, issuer, nonce string, expiry time.Time) string {
-	t.Helper()
-	return jwt.EncodeF(t, func(claims *jwt.Claims) {
-		claims.Issuer = issuer
-		claims.Subject = "SUBJECT"
-		claims.IssuedAt = time.Now().Unix()
-		claims.ExpiresAt = expiry.Unix()
-		claims.Audience = []string{"kubernetes", "system"}
-		claims.Nonce = nonce
-		claims.Groups = []string{"admin", "users"}
-	})
-}
-
-func setupAuthCodeFlow(t *testing.T, provider *mock_idp.MockProvider, serverURL, scope string, extraParams map[string]string, idToken *string) {
-	var nonce string
-	provider.EXPECT().Discovery().Return(idp.NewDiscoveryResponse(serverURL))
-	provider.EXPECT().GetCertificates().Return(idp.NewCertificatesResponse(jwt.PrivateKey))
-	provider.EXPECT().AuthenticateCode(gomock.Any()).
-		DoAndReturn(func(req idp.AuthenticationRequest) (string, error) {
-			if req.Scope != scope {
-				t.Errorf("scope wants `%s` but was `%s`", scope, req.Scope)
-			}
-			for k, v := range extraParams {
-				got := req.RawQuery.Get(k)
-				if got != v {
-					t.Errorf("parameter %s wants `%s` but was `%s`", k, v, got)
-				}
-			}
-			nonce = req.Nonce
-			return "YOUR_AUTH_CODE", nil
-		})
-	provider.EXPECT().Exchange("YOUR_AUTH_CODE").
-		DoAndReturn(func(string) (*idp.TokenResponse, error) {
-			*idToken = newIDToken(t, serverURL, nonce, tokenExpiryFuture)
-			return idp.NewTokenResponse(*idToken, "YOUR_REFRESH_TOKEN"), nil
-		})
-}
-
-func setupROPCFlow(provider *mock_idp.MockProvider, serverURL, scope, username, password, idToken string) {
-	provider.EXPECT().Discovery().Return(idp.NewDiscoveryResponse(serverURL))
-	provider.EXPECT().GetCertificates().Return(idp.NewCertificatesResponse(jwt.PrivateKey))
-	provider.EXPECT().AuthenticatePassword(username, password, scope).
-		Return(idp.NewTokenResponse(idToken, "YOUR_REFRESH_TOKEN"), nil)
-}
-
-func newBrowserMock(ctx context.Context, t *testing.T, ctrl *gomock.Controller, k keys.Keys) browser.Interface {
-	b := mock_browser.NewMockInterface(ctrl)
-	b.EXPECT().
-		Open(gomock.Any()).
-		Do(func(url string) {
-			client := http.Client{Transport: &http.Transport{TLSClientConfig: k.TLSConfig}}
-			req, err := http.NewRequest("GET", url, nil)
-			if err != nil {
-				t.Errorf("could not create a request: %s", err)
-				return
-			}
-			req = req.WithContext(ctx)
-			resp, err := client.Do(req)
-			if err != nil {
-				t.Errorf("could not send a request: %s", err)
-				return
-			}
-			defer resp.Body.Close()
-			if resp.StatusCode != 200 {
-				t.Errorf("StatusCode wants 200 but %d", resp.StatusCode)
-			}
-		})
-	return b
-}

integration_test/httpdriver/http_driver.go

@@ -0,0 +1,54 @@
+// Package httpdriver provides a test double of the browser.
+package httpdriver
+
+import (
+	"context"
+	"crypto/tls"
+	"net/http"
+	"testing"
+)
+
+// New returns a client to simulate browser access.
+func New(ctx context.Context, t *testing.T, tlsConfig *tls.Config) *client {
+	return &client{ctx, t, tlsConfig}
+}
+
+// Zero returns a client which call is not expected.
+func Zero(t *testing.T) *zeroClient {
+	return &zeroClient{t}
+}
+
+type client struct {
+	ctx       context.Context
+	t         *testing.T
+	tlsConfig *tls.Config
+}
+
+func (c *client) Open(url string) error {
+	client := http.Client{Transport: &http.Transport{TLSClientConfig: c.tlsConfig}}
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		c.t.Errorf("could not create a request: %s", err)
+		return nil
+	}
+	req = req.WithContext(c.ctx)
+	resp, err := client.Do(req)
+	if err != nil {
+		c.t.Errorf("could not send a request: %s", err)
+		return nil
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != 200 {
+		c.t.Errorf("StatusCode wants 200 but %d", resp.StatusCode)
+	}
+	return nil
+}
+
+type zeroClient struct {
+	t *testing.T
+}
+
+func (c *zeroClient) Open(url string) error {
+	c.t.Errorf("unexpected function call Open(%s)", url)
+	return nil
+}

integration_test/idp/mock_idp/mock_idp.go

@@ -1,122 +0,0 @@
-// Code generated by MockGen. DO NOT EDIT.
-// Source: github.com/int128/kubelogin/integration_test/idp (interfaces: Provider)
-
-// Package mock_idp is a generated GoMock package.
-package mock_idp
-
-import (
-	gomock "github.com/golang/mock/gomock"
-	idp "github.com/int128/kubelogin/integration_test/idp"
-	reflect "reflect"
-)
-
-// MockProvider is a mock of Provider interface
-type MockProvider struct {
-	ctrl     *gomock.Controller
-	recorder *MockProviderMockRecorder
-}
-
-// MockProviderMockRecorder is the mock recorder for MockProvider
-type MockProviderMockRecorder struct {
-	mock *MockProvider
-}
-
-// NewMockProvider creates a new mock instance
-func NewMockProvider(ctrl *gomock.Controller) *MockProvider {
-	mock := &MockProvider{ctrl: ctrl}
-	mock.recorder = &MockProviderMockRecorder{mock}
-	return mock
-}
-
-// EXPECT returns an object that allows the caller to indicate expected use
-func (m *MockProvider) EXPECT() *MockProviderMockRecorder {
-	return m.recorder
-}
-
-// AuthenticateCode mocks base method
-func (m *MockProvider) AuthenticateCode(arg0 idp.AuthenticationRequest) (string, error) {
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "AuthenticateCode", arg0)
-	ret0, _ := ret[0].(string)
-	ret1, _ := ret[1].(error)
-	return ret0, ret1
-}
-
-// AuthenticateCode indicates an expected call of AuthenticateCode
-func (mr *MockProviderMockRecorder) AuthenticateCode(arg0 interface{}) *gomock.Call {
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "AuthenticateCode", reflect.TypeOf((*MockProvider)(nil).AuthenticateCode), arg0)
-}
-
-// AuthenticatePassword mocks base method
-func (m *MockProvider) AuthenticatePassword(arg0, arg1, arg2 string) (*idp.TokenResponse, error) {
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "AuthenticatePassword", arg0, arg1, arg2)
-	ret0, _ := ret[0].(*idp.TokenResponse)
-	ret1, _ := ret[1].(error)
-	return ret0, ret1
-}
-
-// AuthenticatePassword indicates an expected call of AuthenticatePassword
-func (mr *MockProviderMockRecorder) AuthenticatePassword(arg0, arg1, arg2 interface{}) *gomock.Call {
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "AuthenticatePassword", reflect.TypeOf((*MockProvider)(nil).AuthenticatePassword), arg0, arg1, arg2)
-}
-
-// Discovery mocks base method
-func (m *MockProvider) Discovery() *idp.DiscoveryResponse {
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "Discovery")
-	ret0, _ := ret[0].(*idp.DiscoveryResponse)
-	return ret0
-}
-
-// Discovery indicates an expected call of Discovery
-func (mr *MockProviderMockRecorder) Discovery() *gomock.Call {
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Discovery", reflect.TypeOf((*MockProvider)(nil).Discovery))
-}
-
-// Exchange mocks base method
-func (m *MockProvider) Exchange(arg0 string) (*idp.TokenResponse, error) {
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "Exchange", arg0)
-	ret0, _ := ret[0].(*idp.TokenResponse)
-	ret1, _ := ret[1].(error)
-	return ret0, ret1
-}
-
-// Exchange indicates an expected call of Exchange
-func (mr *MockProviderMockRecorder) Exchange(arg0 interface{}) *gomock.Call {
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Exchange", reflect.TypeOf((*MockProvider)(nil).Exchange), arg0)
-}
-
-// GetCertificates mocks base method
-func (m *MockProvider) GetCertificates() *idp.CertificatesResponse {
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "GetCertificates")
-	ret0, _ := ret[0].(*idp.CertificatesResponse)
-	return ret0
-}
-
-// GetCertificates indicates an expected call of GetCertificates
-func (mr *MockProviderMockRecorder) GetCertificates() *gomock.Call {
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetCertificates", reflect.TypeOf((*MockProvider)(nil).GetCertificates))
-}
-
-// Refresh mocks base method
-func (m *MockProvider) Refresh(arg0 string) (*idp.TokenResponse, error) {
-	m.ctrl.T.Helper()
-	ret := m.ctrl.Call(m, "Refresh", arg0)
-	ret0, _ := ret[0].(*idp.TokenResponse)
-	ret1, _ := ret[1].(error)
-	return ret0, ret1
-}
-
-// Refresh indicates an expected call of Refresh
-func (mr *MockProviderMockRecorder) Refresh(arg0 interface{}) *gomock.Call {
-	mr.mock.ctrl.T.Helper()
-	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Refresh", reflect.TypeOf((*MockProvider)(nil).Refresh), arg0)
-}

integration_test/keypair/keypair.go

@@ -1,4 +1,4 @@
-package keys
+package keypair
 
 import (
 	"crypto/tls"
@@ -10,8 +10,8 @@ import (
 	"strings"
 )
 
-// Keys represents a pair of certificate and key.
-type Keys struct {
+// KeyPair represents a pair of certificate and key.
+type KeyPair struct {
 	CertPath     string
 	KeyPath      string
 	CACertPath   string
@@ -20,16 +20,16 @@ type Keys struct {
 }
 
 // None represents non-TLS.
-var None Keys
+var None KeyPair
 
-// Server is a Keys for TLS server.
+// Server is a KeyPair for TLS server.
 // These files should be generated by Makefile before test.
-var Server = Keys{
-	CertPath:     "keys/testdata/server.crt",
-	KeyPath:      "keys/testdata/server.key",
-	CACertPath:   "keys/testdata/ca.crt",
-	CACertBase64: readAsBase64("keys/testdata/ca.crt"),
-	TLSConfig:    newTLSConfig("keys/testdata/ca.crt"),
+var Server = KeyPair{
+	CertPath:     "keypair/testdata/server.crt",
+	KeyPath:      "keypair/testdata/server.key",
+	CACertPath:   "keypair/testdata/ca.crt",
+	CACertBase64: readAsBase64("keypair/testdata/ca.crt"),
+	TLSConfig:    newTLSConfig("keypair/testdata/ca.crt"),
 }
 
 func readAsBase64(name string) string {

integration_test/oidcserver/handler/handler.go

@@ -1,4 +1,5 @@
-package idp
+// Package handler provides a HTTP handler for the OpenID Connect Provider.
+package handler
 
 import (
 	"encoding/json"
@@ -9,7 +10,7 @@ import (
 	"golang.org/x/xerrors"
 )
 
-func NewHandler(t *testing.T, provider Provider) *Handler {
+func New(t *testing.T, provider Provider) *Handler {
 	return &Handler{t, provider}
 }
 
@@ -71,16 +72,16 @@ func (h *Handler) serveHTTP(w http.ResponseWriter, r *http.Request) error {
 			return xerrors.Errorf("could not render json: %w", err)
 		}
 	case m == "GET" && p == "/auth":
-		// 3.1.2.1. Authentication Request
-		// https://openid.net/specs/openid-connect-core-1_0.html#AuthRequest
 		q := r.URL.Query()
 		redirectURI, state := q.Get("redirect_uri"), q.Get("state")
 		code, err := h.provider.AuthenticateCode(AuthenticationRequest{
-			RedirectURI: redirectURI,
-			State:       state,
-			Scope:       q.Get("scope"),
-			Nonce:       q.Get("nonce"),
-			RawQuery:    q,
+			RedirectURI:         redirectURI,
+			State:               state,
+			Scope:               q.Get("scope"),
+			Nonce:               q.Get("nonce"),
+			CodeChallenge:       q.Get("code_challenge"),
+			CodeChallengeMethod: q.Get("code_challenge_method"),
+			RawQuery:            q,
 		})
 		if err != nil {
 			return xerrors.Errorf("authentication error: %w", err)
@@ -94,10 +95,10 @@ func (h *Handler) serveHTTP(w http.ResponseWriter, r *http.Request) error {
 		grantType := r.Form.Get("grant_type")
 		switch grantType {
 		case "authorization_code":
-			// 3.1.3.1. Token Request
-			// https://openid.net/specs/openid-connect-core-1_0.html#TokenRequest
-			code := r.Form.Get("code")
-			tokenResponse, err := h.provider.Exchange(code)
+			tokenResponse, err := h.provider.Exchange(TokenRequest{
+				Code:         r.Form.Get("code"),
+				CodeVerifier: r.Form.Get("code_verifier"),
+			})
 			if err != nil {
 				return xerrors.Errorf("token request error: %w", err)
 			}

integration_test/oidcserver/handler/types.go

@@ -1,13 +1,7 @@
-// Package idp provides a test double of an OpenID Connect Provider.
-package idp
-
-//go:generate mockgen -destination mock_idp/mock_idp.go github.com/int128/kubelogin/integration_test/idp Provider
+package handler
 
 import (
-	"crypto/rsa"
-	"encoding/base64"
 	"fmt"
-	"math/big"
 	"net/url"
 )
 
@@ -19,7 +13,7 @@ type Provider interface {
 	Discovery() *DiscoveryResponse
 	GetCertificates() *CertificatesResponse
 	AuthenticateCode(req AuthenticationRequest) (code string, err error)
-	Exchange(code string) (*TokenResponse, error)
+	Exchange(req TokenRequest) (*TokenResponse, error)
 	AuthenticatePassword(username, password, scope string) (*TokenResponse, error)
 	Refresh(refreshToken string) (*TokenResponse, error)
 }
@@ -40,26 +34,6 @@ type DiscoveryResponse struct {
 	CodeChallengeMethodsSupported     []string `json:"code_challenge_methods_supported"`
 }
 
-// NewDiscoveryResponse returns a DiscoveryResponse for the local server.
-// This is based on https://accounts.google.com/.well-known/openid-configuration.
-func NewDiscoveryResponse(issuer string) *DiscoveryResponse {
-	return &DiscoveryResponse{
-		Issuer:                            issuer,
-		AuthorizationEndpoint:             issuer + "/auth",
-		TokenEndpoint:                     issuer + "/token",
-		JwksURI:                           issuer + "/certs",
-		UserinfoEndpoint:                  issuer + "/userinfo",
-		RevocationEndpoint:                issuer + "/revoke",
-		ResponseTypesSupported:            []string{"code id_token"},
-		SubjectTypesSupported:             []string{"public"},
-		IDTokenSigningAlgValuesSupported:  []string{"RS256"},
-		ScopesSupported:                   []string{"openid", "email", "profile"},
-		TokenEndpointAuthMethodsSupported: []string{"client_secret_post", "client_secret_basic"},
-		CodeChallengeMethodsSupported:     []string{"plain", "S256"},
-		ClaimsSupported:                   []string{"aud", "email", "exp", "iat", "iss", "name", "sub"},
-	}
-}
-
 type CertificatesResponse struct {
 	Keys []*CertificatesResponseKey `json:"keys"`
 }
@@ -73,29 +47,23 @@ type CertificatesResponseKey struct {
 	E   string `json:"e"`
 }
 
-// NewCertificatesResponse returns a CertificatesResponse using the key pair.
-// This is used for verifying a signature of ID token.
-func NewCertificatesResponse(idTokenKeyPair *rsa.PrivateKey) *CertificatesResponse {
-	return &CertificatesResponse{
-		Keys: []*CertificatesResponseKey{
-			{
-				Kty: "RSA",
-				Alg: "RS256",
-				Use: "sig",
-				Kid: "dummy",
-				E:   base64.RawURLEncoding.EncodeToString(big.NewInt(int64(idTokenKeyPair.E)).Bytes()),
-				N:   base64.RawURLEncoding.EncodeToString(idTokenKeyPair.N.Bytes()),
-			},
-		},
-	}
+// AuthenticationRequest represents a type of:
+// https://openid.net/specs/openid-connect-core-1_0.html#AuthRequest
+type AuthenticationRequest struct {
+	RedirectURI         string
+	State               string
+	Scope               string // space separated string
+	Nonce               string
+	CodeChallenge       string
+	CodeChallengeMethod string
+	RawQuery            url.Values
 }
 
-type AuthenticationRequest struct {
-	RedirectURI string
-	State       string
-	Scope       string // space separated string
-	Nonce       string
-	RawQuery    url.Values
+// TokenRequest represents a type of:
+// https://openid.net/specs/openid-connect-core-1_0.html#TokenRequest
+type TokenRequest struct {
+	Code         string
+	CodeVerifier string
 }
 
 type TokenResponse struct {
@@ -106,17 +74,6 @@ type TokenResponse struct {
 	IDToken      string `json:"id_token"`
 }
 
-// NewTokenResponse returns a TokenResponse.
-func NewTokenResponse(idToken, refreshToken string) *TokenResponse {
-	return &TokenResponse{
-		TokenType:    "Bearer",
-		ExpiresIn:    3600,
-		AccessToken:  "YOUR_ACCESS_TOKEN",
-		IDToken:      idToken,
-		RefreshToken: refreshToken,
-	}
-}
-
 // ErrorResponse represents an error response described in the following section:
 // 5.2 Error Response
 // https://tools.ietf.org/html/rfc6749#section-5.2

integration_test/oidcserver/http/http.go

@@ -1,7 +1,5 @@
-// Package localserver provides a http server running on localhost.
-// This is only for testing.
-//
-package localserver
+// Package http provides a http server running on localhost for testing.
+package http
 
 import (
 	"context"
@@ -9,7 +7,7 @@ import (
 	"net/http"
 	"testing"
 
-	"github.com/int128/kubelogin/integration_test/keys"
+	"github.com/int128/kubelogin/integration_test/keypair"
 )
 
 type Shutdowner interface {
@@ -17,28 +15,23 @@ type Shutdowner interface {
 }
 
 type shutdowner struct {
-	l net.Listener
 	s *http.Server
 }
 
 func (s *shutdowner) Shutdown(t *testing.T, ctx context.Context) {
-	// s.Shutdown() closes the lister as well,
-	// so we do not need to call l.Close() explicitly
 	if err := s.s.Shutdown(ctx); err != nil {
-		t.Errorf("Could not shutdown the server: %s", err)
+		t.Errorf("could not shutdown the server: %s", err)
 	}
 }
 
-// Start starts an authentication server.
-// If k is non-nil, it starts a TLS server.
-func Start(t *testing.T, h http.Handler, k keys.Keys) (string, Shutdowner) {
-	if k == keys.None {
+func Start(t *testing.T, h http.Handler, k keypair.KeyPair) (string, Shutdowner) {
+	if k == keypair.None {
 		return startNoTLS(t, h)
 	}
 	return startTLS(t, h, k)
 }
 
-func startNoTLS(t *testing.T, h http.Handler) (string, Shutdowner) {
+func startNoTLS(t *testing.T, h http.Handler) (string, *shutdowner) {
 	t.Helper()
 	l, port := newLocalhostListener(t)
 	url := "http://localhost:" + port
@@ -51,10 +44,10 @@ func startNoTLS(t *testing.T, h http.Handler) (string, Shutdowner) {
 			t.Error(err)
 		}
 	}()
-	return url, &shutdowner{l, s}
+	return url, &shutdowner{s}
 }
 
-func startTLS(t *testing.T, h http.Handler, k keys.Keys) (string, Shutdowner) {
+func startTLS(t *testing.T, h http.Handler, k keypair.KeyPair) (string, *shutdowner) {
 	t.Helper()
 	l, port := newLocalhostListener(t)
 	url := "https://localhost:" + port
@@ -67,7 +60,7 @@ func startTLS(t *testing.T, h http.Handler, k keys.Keys) (string, Shutdowner) {
 			t.Error(err)
 		}
 	}()
-	return url, &shutdowner{l, s}
+	return url, &shutdowner{s}
 }
 
 func newLocalhostListener(t *testing.T) (net.Listener, string) {

integration_test/oidcserver/server.go

@@ -0,0 +1,217 @@
+// Package oidcserver provides a stub of OpenID Connect provider.
+package oidcserver
+
+import (
+	"crypto/sha256"
+	"encoding/base64"
+	"math/big"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/int128/kubelogin/integration_test/keypair"
+	"github.com/int128/kubelogin/integration_test/oidcserver/handler"
+	"github.com/int128/kubelogin/integration_test/oidcserver/http"
+	"github.com/int128/kubelogin/pkg/testing/jwt"
+	"golang.org/x/xerrors"
+)
+
+type Server interface {
+	http.Shutdowner
+	IssuerURL() string
+	SetConfig(Config)
+	LastTokenResponse() *handler.TokenResponse
+}
+
+// Want represents a set of expected values.
+type Want struct {
+	Scope               string
+	RedirectURIPrefix   string
+	CodeChallengeMethod string            // optional
+	ExtraParams         map[string]string // optional
+	Username            string            // optional
+	Password            string            // optional
+	RefreshToken        string            // optional
+}
+
+// Response represents a set of response values.
+type Response struct {
+	IDTokenExpiry                 time.Time
+	RefreshToken                  string
+	RefreshError                  string   // if set, Refresh() will return the error
+	CodeChallengeMethodsSupported []string // optional
+}
+
+// Config represents a configuration of the OpenID Connect provider.
+type Config struct {
+	Want     Want
+	Response Response
+}
+
+// New starts a HTTP server for the OpenID Connect provider.
+func New(t *testing.T, k keypair.KeyPair, c Config) Server {
+	sv := server{Config: c, t: t}
+	sv.issuerURL, sv.Shutdowner = http.Start(t, handler.New(t, &sv), k)
+	return &sv
+}
+
+type server struct {
+	Config
+	http.Shutdowner
+	t                         *testing.T
+	issuerURL                 string
+	lastAuthenticationRequest *handler.AuthenticationRequest
+	lastTokenResponse         *handler.TokenResponse
+}
+
+func (sv *server) IssuerURL() string {
+	return sv.issuerURL
+}
+
+func (sv *server) SetConfig(cfg Config) {
+	sv.Config = cfg
+}
+
+func (sv *server) LastTokenResponse() *handler.TokenResponse {
+	return sv.lastTokenResponse
+}
+
+func (sv *server) Discovery() *handler.DiscoveryResponse {
+	// based on https://accounts.google.com/.well-known/openid-configuration
+	return &handler.DiscoveryResponse{
+		Issuer:                            sv.issuerURL,
+		AuthorizationEndpoint:             sv.issuerURL + "/auth",
+		TokenEndpoint:                     sv.issuerURL + "/token",
+		JwksURI:                           sv.issuerURL + "/certs",
+		UserinfoEndpoint:                  sv.issuerURL + "/userinfo",
+		RevocationEndpoint:                sv.issuerURL + "/revoke",
+		ResponseTypesSupported:            []string{"code id_token"},
+		SubjectTypesSupported:             []string{"public"},
+		IDTokenSigningAlgValuesSupported:  []string{"RS256"},
+		ScopesSupported:                   []string{"openid", "email", "profile"},
+		TokenEndpointAuthMethodsSupported: []string{"client_secret_post", "client_secret_basic"},
+		CodeChallengeMethodsSupported:     sv.Config.Response.CodeChallengeMethodsSupported,
+		ClaimsSupported:                   []string{"aud", "email", "exp", "iat", "iss", "name", "sub"},
+	}
+}
+
+func (sv *server) GetCertificates() *handler.CertificatesResponse {
+	idTokenKeyPair := jwt.PrivateKey
+	return &handler.CertificatesResponse{
+		Keys: []*handler.CertificatesResponseKey{
+			{
+				Kty: "RSA",
+				Alg: "RS256",
+				Use: "sig",
+				Kid: "dummy",
+				E:   base64.RawURLEncoding.EncodeToString(big.NewInt(int64(idTokenKeyPair.E)).Bytes()),
+				N:   base64.RawURLEncoding.EncodeToString(idTokenKeyPair.N.Bytes()),
+			},
+		},
+	}
+}
+
+func (sv *server) AuthenticateCode(req handler.AuthenticationRequest) (code string, err error) {
+	if req.Scope != sv.Want.Scope {
+		sv.t.Errorf("scope wants `%s` but was `%s`", sv.Want.Scope, req.Scope)
+	}
+	if !strings.HasPrefix(req.RedirectURI, sv.Want.RedirectURIPrefix) {
+		sv.t.Errorf("redirectURI wants prefix `%s` but was `%s`", sv.Want.RedirectURIPrefix, req.RedirectURI)
+	}
+	if req.CodeChallengeMethod != sv.Want.CodeChallengeMethod {
+		sv.t.Errorf("code_challenge_method wants `%s` but was `%s`", sv.Want.CodeChallengeMethod, req.CodeChallengeMethod)
+	}
+	for k, v := range sv.Want.ExtraParams {
+		got := req.RawQuery.Get(k)
+		if got != v {
+			sv.t.Errorf("parameter %s wants `%s` but was `%s`", k, v, got)
+		}
+	}
+	sv.lastAuthenticationRequest = &req
+	return "YOUR_AUTH_CODE", nil
+}
+
+func (sv *server) Exchange(req handler.TokenRequest) (*handler.TokenResponse, error) {
+	if req.Code != "YOUR_AUTH_CODE" {
+		return nil, xerrors.Errorf("code wants %s but was %s", "YOUR_AUTH_CODE", req.Code)
+	}
+	if sv.lastAuthenticationRequest.CodeChallengeMethod == "S256" {
+		// https://tools.ietf.org/html/rfc7636#section-4.6
+		challenge := computeS256Challenge(req.CodeVerifier)
+		if challenge != sv.lastAuthenticationRequest.CodeChallenge {
+			sv.t.Errorf("pkce S256 challenge did not match (want %s but was %s)", sv.lastAuthenticationRequest.CodeChallenge, challenge)
+		}
+	}
+	resp := &handler.TokenResponse{
+		TokenType:    "Bearer",
+		ExpiresIn:    3600,
+		AccessToken:  "YOUR_ACCESS_TOKEN",
+		RefreshToken: sv.Response.RefreshToken,
+		IDToken: jwt.EncodeF(sv.t, func(claims *jwt.Claims) {
+			claims.Issuer = sv.issuerURL
+			claims.Subject = "SUBJECT"
+			claims.IssuedAt = sv.Response.IDTokenExpiry.Add(-time.Hour).Unix()
+			claims.ExpiresAt = sv.Response.IDTokenExpiry.Unix()
+			claims.Audience = []string{"kubernetes"}
+			claims.Nonce = sv.lastAuthenticationRequest.Nonce
+		}),
+	}
+	sv.lastTokenResponse = resp
+	return resp, nil
+}
+
+func computeS256Challenge(verifier string) string {
+	c := sha256.Sum256([]byte(verifier))
+	return base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString(c[:])
+}
+
+func (sv *server) AuthenticatePassword(username, password, scope string) (*handler.TokenResponse, error) {
+	if scope != sv.Want.Scope {
+		sv.t.Errorf("scope wants `%s` but was `%s`", sv.Want.Scope, scope)
+	}
+	if username != sv.Want.Username {
+		sv.t.Errorf("username wants `%s` but was `%s`", sv.Want.Username, username)
+	}
+	if password != sv.Want.Password {
+		sv.t.Errorf("password wants `%s` but was `%s`", sv.Want.Password, password)
+	}
+	resp := &handler.TokenResponse{
+		TokenType:    "Bearer",
+		ExpiresIn:    3600,
+		AccessToken:  "YOUR_ACCESS_TOKEN",
+		RefreshToken: sv.Response.RefreshToken,
+		IDToken: jwt.EncodeF(sv.t, func(claims *jwt.Claims) {
+			claims.Issuer = sv.issuerURL
+			claims.Subject = "SUBJECT"
+			claims.IssuedAt = sv.Response.IDTokenExpiry.Add(-time.Hour).Unix()
+			claims.ExpiresAt = sv.Response.IDTokenExpiry.Unix()
+			claims.Audience = []string{"kubernetes"}
+		}),
+	}
+	sv.lastTokenResponse = resp
+	return resp, nil
+}
+
+func (sv *server) Refresh(refreshToken string) (*handler.TokenResponse, error) {
+	if refreshToken != sv.Want.RefreshToken {
+		sv.t.Errorf("refreshToken wants %s but was %s", sv.Want.RefreshToken, refreshToken)
+	}
+	if sv.Response.RefreshError != "" {
+		return nil, &handler.ErrorResponse{Code: "invalid_request", Description: sv.Response.RefreshError}
+	}
+	resp := &handler.TokenResponse{
+		TokenType:    "Bearer",
+		ExpiresIn:    3600,
+		AccessToken:  "YOUR_ACCESS_TOKEN",
+		RefreshToken: sv.Response.RefreshToken,
+		IDToken: jwt.EncodeF(sv.t, func(claims *jwt.Claims) {
+			claims.Issuer = sv.issuerURL
+			claims.Subject = "SUBJECT"
+			claims.IssuedAt = sv.Response.IDTokenExpiry.Add(-time.Hour).Unix()
+			claims.ExpiresAt = sv.Response.IDTokenExpiry.Unix()
+			claims.Audience = []string{"kubernetes"}
+		}),
+	}
+	sv.lastTokenResponse = resp
+	return resp, nil
+}

integration_test/standalone_test.go

@@ -6,16 +6,13 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang/mock/gomock"
-	"github.com/int128/kubelogin/integration_test/idp"
-	"github.com/int128/kubelogin/integration_test/idp/mock_idp"
-	"github.com/int128/kubelogin/integration_test/keys"
+	"github.com/int128/kubelogin/integration_test/httpdriver"
+	"github.com/int128/kubelogin/integration_test/keypair"
 	"github.com/int128/kubelogin/integration_test/kubeconfig"
-	"github.com/int128/kubelogin/integration_test/localserver"
+	"github.com/int128/kubelogin/integration_test/oidcserver"
 	"github.com/int128/kubelogin/pkg/adaptors/browser"
-	"github.com/int128/kubelogin/pkg/adaptors/browser/mock_browser"
 	"github.com/int128/kubelogin/pkg/di"
-	"github.com/int128/kubelogin/pkg/testing/jwt"
+	"github.com/int128/kubelogin/pkg/testing/clock"
 	"github.com/int128/kubelogin/pkg/testing/logger"
 )
 
@@ -27,207 +24,241 @@ import (
 // 4. Verify the kubeconfig.
 //
 func TestStandalone(t *testing.T) {
-	t.Run("NoTLS", func(t *testing.T) {
-		testStandalone(t, keys.None)
-	})
-	t.Run("TLS", func(t *testing.T) {
-		testStandalone(t, keys.Server)
-	})
-}
+	timeout := 3 * time.Second
+	now := time.Date(2020, 1, 1, 0, 0, 0, 0, time.UTC)
 
-func testStandalone(t *testing.T, idpTLS keys.Keys) {
-	timeout := 5 * time.Second
+	for name, tc := range map[string]struct {
+		keyPair keypair.KeyPair
+		args    []string
+	}{
+		"NoTLS": {},
+		"TLS": {
+			keyPair: keypair.Server,
+		},
+	} {
+		t.Run(name, func(t *testing.T) {
+			t.Run("AuthCode", func(t *testing.T) {
+				t.Parallel()
+				ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+				defer cancel()
+				sv := oidcserver.New(t, tc.keyPair, oidcserver.Config{
+					Want: oidcserver.Want{
+						Scope:             "openid",
+						RedirectURIPrefix: "http://localhost:",
+					},
+					Response: oidcserver.Response{
+						IDTokenExpiry: now.Add(time.Hour),
+					},
+				})
+				defer sv.Shutdown(t, ctx)
+				kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
+					Issuer:                  sv.IssuerURL(),
+					IDPCertificateAuthority: tc.keyPair.CACertPath,
+				})
+				defer os.Remove(kubeConfigFilename)
+				runStandalone(t, ctx, standaloneConfig{
+					issuerURL:          sv.IssuerURL(),
+					kubeConfigFilename: kubeConfigFilename,
+					httpDriver:         httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+					now:                now,
+				})
+				kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
+					IDToken:      sv.LastTokenResponse().IDToken,
+					RefreshToken: sv.LastTokenResponse().RefreshToken,
+				})
+			})
 
-	t.Run("Defaults", func(t *testing.T) {
+			t.Run("ROPC", func(t *testing.T) {
+				t.Parallel()
+				ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+				defer cancel()
+				sv := oidcserver.New(t, tc.keyPair, oidcserver.Config{
+					Want: oidcserver.Want{
+						Scope:             "openid",
+						RedirectURIPrefix: "http://localhost:",
+						Username:          "USER1",
+						Password:          "PASS1",
+					},
+					Response: oidcserver.Response{
+						IDTokenExpiry: now.Add(time.Hour),
+					},
+				})
+				defer sv.Shutdown(t, ctx)
+				kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
+					Issuer:                  sv.IssuerURL(),
+					IDPCertificateAuthority: tc.keyPair.CACertPath,
+				})
+				defer os.Remove(kubeConfigFilename)
+				runStandalone(t, ctx, standaloneConfig{
+					issuerURL:          sv.IssuerURL(),
+					kubeConfigFilename: kubeConfigFilename,
+					httpDriver:         httpdriver.Zero(t),
+					now:                now,
+					args: []string{
+						"--username", "USER1",
+						"--password", "PASS1",
+					},
+				})
+				kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
+					IDToken:      sv.LastTokenResponse().IDToken,
+					RefreshToken: sv.LastTokenResponse().RefreshToken,
+				})
+			})
+
+			t.Run("TokenLifecycle", func(t *testing.T) {
+				t.Parallel()
+				ctx, cancel := context.WithTimeout(context.TODO(), timeout)
+				defer cancel()
+				sv := oidcserver.New(t, tc.keyPair, oidcserver.Config{})
+				defer sv.Shutdown(t, ctx)
+				kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
+					Issuer:                  sv.IssuerURL(),
+					IDPCertificateAuthority: tc.keyPair.CACertPath,
+				})
+				defer os.Remove(kubeConfigFilename)
+
+				t.Run("NoToken", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{
+						Want: oidcserver.Want{
+							Scope:             "openid",
+							RedirectURIPrefix: "http://localhost:",
+						},
+						Response: oidcserver.Response{
+							IDTokenExpiry: now.Add(time.Hour),
+							RefreshToken:  "REFRESH_TOKEN_1",
+						},
+					})
+					runStandalone(t, ctx, standaloneConfig{
+						issuerURL:          sv.IssuerURL(),
+						kubeConfigFilename: kubeConfigFilename,
+						httpDriver:         httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+						now:                now,
+					})
+					kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
+						IDToken:      sv.LastTokenResponse().IDToken,
+						RefreshToken: "REFRESH_TOKEN_1",
+					})
+				})
+				t.Run("Valid", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{})
+					runStandalone(t, ctx, standaloneConfig{
+						issuerURL:          sv.IssuerURL(),
+						kubeConfigFilename: kubeConfigFilename,
+						httpDriver:         httpdriver.Zero(t),
+						now:                now,
+					})
+					kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
+						IDToken:      sv.LastTokenResponse().IDToken,
+						RefreshToken: "REFRESH_TOKEN_1",
+					})
+				})
+				t.Run("Refresh", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{
+						Want: oidcserver.Want{
+							Scope:             "openid",
+							RedirectURIPrefix: "http://localhost:",
+							RefreshToken:      "REFRESH_TOKEN_1",
+						},
+						Response: oidcserver.Response{
+							IDTokenExpiry: now.Add(3 * time.Hour),
+							RefreshToken:  "REFRESH_TOKEN_2",
+						},
+					})
+					runStandalone(t, ctx, standaloneConfig{
+						issuerURL:          sv.IssuerURL(),
+						kubeConfigFilename: kubeConfigFilename,
+						httpDriver:         httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+						now:                now.Add(2 * time.Hour),
+					})
+					kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
+						IDToken:      sv.LastTokenResponse().IDToken,
+						RefreshToken: "REFRESH_TOKEN_2",
+					})
+				})
+				t.Run("RefreshAgain", func(t *testing.T) {
+					sv.SetConfig(oidcserver.Config{
+						Want: oidcserver.Want{
+							Scope:             "openid",
+							RedirectURIPrefix: "http://localhost:",
+							RefreshToken:      "REFRESH_TOKEN_2",
+						},
+						Response: oidcserver.Response{
+							IDTokenExpiry: now.Add(5 * time.Hour),
+						},
+					})
+					runStandalone(t, ctx, standaloneConfig{
+						issuerURL:          sv.IssuerURL(),
+						kubeConfigFilename: kubeConfigFilename,
+						httpDriver:         httpdriver.New(ctx, t, tc.keyPair.TLSConfig),
+						now:                now.Add(4 * time.Hour),
+					})
+					kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
+						IDToken:      sv.LastTokenResponse().IDToken,
+						RefreshToken: "REFRESH_TOKEN_2",
+					})
+				})
+			})
+		})
+	}
+
+	t.Run("TLSData", func(t *testing.T) {
 		t.Parallel()
 		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
 		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), idpTLS)
-		defer server.Shutdown(t, ctx)
-		browserMock := newBrowserMock(ctx, t, ctrl, idpTLS)
-		var idToken string
-		setupAuthCodeFlow(t, provider, serverURL, "openid", nil, &idToken)
+		sv := oidcserver.New(t, keypair.Server, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:             "openid",
+				RedirectURIPrefix: "http://localhost:",
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry: now.Add(time.Hour),
+			},
+		})
+		defer sv.Shutdown(t, ctx)
 		kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
-			Issuer:                  serverURL,
-			IDPCertificateAuthority: idpTLS.CACertPath,
+			Issuer:                      sv.IssuerURL(),
+			IDPCertificateAuthorityData: keypair.Server.CACertBase64,
 		})
 		defer os.Remove(kubeConfigFilename)
-
-		args := []string{
-			"--kubeconfig", kubeConfigFilename,
-		}
-		runRootCmd(t, ctx, browserMock, args)
+		runStandalone(t, ctx, standaloneConfig{
+			issuerURL:          sv.IssuerURL(),
+			kubeConfigFilename: kubeConfigFilename,
+			httpDriver:         httpdriver.New(ctx, t, keypair.Server.TLSConfig),
+			now:                now,
+		})
 		kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
-		})
-	})
-
-	t.Run("ResourceOwnerPasswordCredentials", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), idpTLS)
-		defer server.Shutdown(t, ctx)
-		browserMock := mock_browser.NewMockInterface(ctrl)
-		idToken := newIDToken(t, serverURL, "", tokenExpiryFuture)
-		setupROPCFlow(provider, serverURL, "openid", "USER", "PASS", idToken)
-		kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
-			Issuer:                  serverURL,
-			IDPCertificateAuthority: idpTLS.CACertPath,
-		})
-		defer os.Remove(kubeConfigFilename)
-
-		args := []string{
-			"--kubeconfig", kubeConfigFilename,
-			"--username", "USER",
-			"--password", "PASS",
-		}
-		runRootCmd(t, ctx, browserMock, args)
-		kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
-		})
-	})
-
-	t.Run("HasValidToken", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), idpTLS)
-		defer server.Shutdown(t, ctx)
-		idToken := newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryFuture)
-		browserMock := mock_browser.NewMockInterface(ctrl)
-
-		kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
-			Issuer:                  serverURL,
-			IDToken:                 idToken,
-			RefreshToken:            "YOUR_REFRESH_TOKEN",
-			IDPCertificateAuthority: idpTLS.CACertPath,
-		})
-		defer os.Remove(kubeConfigFilename)
-
-		args := []string{
-			"--kubeconfig", kubeConfigFilename,
-		}
-		runRootCmd(t, ctx, browserMock, args)
-		kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
-		})
-	})
-
-	t.Run("HasValidRefreshToken", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), idpTLS)
-		defer server.Shutdown(t, ctx)
-		idToken := newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryFuture)
-		provider.EXPECT().Discovery().Return(idp.NewDiscoveryResponse(serverURL))
-		provider.EXPECT().GetCertificates().Return(idp.NewCertificatesResponse(jwt.PrivateKey))
-		provider.EXPECT().Refresh("VALID_REFRESH_TOKEN").
-			Return(idp.NewTokenResponse(idToken, "NEW_REFRESH_TOKEN"), nil)
-		browserMock := mock_browser.NewMockInterface(ctrl)
-
-		kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
-			Issuer:                  serverURL,
-			IDToken:                 newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryPast), // expired
-			RefreshToken:            "VALID_REFRESH_TOKEN",
-			IDPCertificateAuthority: idpTLS.CACertPath,
-		})
-		defer os.Remove(kubeConfigFilename)
-
-		args := []string{
-			"--kubeconfig", kubeConfigFilename,
-		}
-		runRootCmd(t, ctx, browserMock, args)
-		kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
-			IDToken:      idToken,
-			RefreshToken: "NEW_REFRESH_TOKEN",
-		})
-	})
-
-	t.Run("HasExpiredRefreshToken", func(t *testing.T) {
-		t.Parallel()
-		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
-		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), idpTLS)
-		defer server.Shutdown(t, ctx)
-		var idToken string
-		setupAuthCodeFlow(t, provider, serverURL, "openid", nil, &idToken)
-		provider.EXPECT().Refresh("EXPIRED_REFRESH_TOKEN").
-			Return(nil, &idp.ErrorResponse{Code: "invalid_request", Description: "token has expired"}).
-			MaxTimes(2) // package oauth2 will retry refreshing the token
-		browserMock := newBrowserMock(ctx, t, ctrl, idpTLS)
-
-		kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
-			Issuer:                  serverURL,
-			IDToken:                 newIDToken(t, serverURL, "YOUR_NONCE", tokenExpiryPast), // expired
-			RefreshToken:            "EXPIRED_REFRESH_TOKEN",
-			IDPCertificateAuthority: idpTLS.CACertPath,
-		})
-		defer os.Remove(kubeConfigFilename)
-
-		args := []string{
-			"--kubeconfig", kubeConfigFilename,
-		}
-		runRootCmd(t, ctx, browserMock, args)
-		kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
+			IDToken:      sv.LastTokenResponse().IDToken,
+			RefreshToken: sv.LastTokenResponse().RefreshToken,
 		})
 	})
 
 	t.Run("env_KUBECONFIG", func(t *testing.T) {
-		// do not run this in parallel due to change of the env var
 		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
 		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), idpTLS)
-		defer server.Shutdown(t, ctx)
-		var idToken string
-		setupAuthCodeFlow(t, provider, serverURL, "openid", nil, &idToken)
-		browserMock := newBrowserMock(ctx, t, ctrl, idpTLS)
-
+		sv := oidcserver.New(t, keypair.None, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:             "openid",
+				RedirectURIPrefix: "http://localhost:",
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry: now.Add(time.Hour),
+			},
+		})
+		defer sv.Shutdown(t, ctx)
 		kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
-			Issuer:                  serverURL,
-			IDPCertificateAuthority: idpTLS.CACertPath,
+			Issuer: sv.IssuerURL(),
 		})
 		defer os.Remove(kubeConfigFilename)
 		setenv(t, "KUBECONFIG", kubeConfigFilename+string(os.PathListSeparator)+"kubeconfig/testdata/dummy.yaml")
 		defer unsetenv(t, "KUBECONFIG")
-
-		args := []string{
-			"--kubeconfig", kubeConfigFilename,
-		}
-		runRootCmd(t, ctx, browserMock, args)
+		runStandalone(t, ctx, standaloneConfig{
+			issuerURL:  sv.IssuerURL(),
+			httpDriver: httpdriver.New(ctx, t, nil),
+			now:        now,
+		})
 		kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
+			IDToken:      sv.LastTokenResponse().IDToken,
+			RefreshToken: sv.LastTokenResponse().RefreshToken,
 		})
 	})
 
@@ -235,42 +266,49 @@ func testStandalone(t *testing.T, idpTLS keys.Keys) {
 		t.Parallel()
 		ctx, cancel := context.WithTimeout(context.TODO(), timeout)
 		defer cancel()
-		ctrl := gomock.NewController(t)
-		defer ctrl.Finish()
-
-		provider := mock_idp.NewMockProvider(ctrl)
-		serverURL, server := localserver.Start(t, idp.NewHandler(t, provider), idpTLS)
-		defer server.Shutdown(t, ctx)
-		var idToken string
-		setupAuthCodeFlow(t, provider, serverURL, "profile groups openid", nil, &idToken)
-		browserMock := newBrowserMock(ctx, t, ctrl, idpTLS)
-
+		sv := oidcserver.New(t, keypair.None, oidcserver.Config{
+			Want: oidcserver.Want{
+				Scope:             "profile groups openid",
+				RedirectURIPrefix: "http://localhost:",
+			},
+			Response: oidcserver.Response{
+				IDTokenExpiry: now.Add(time.Hour),
+			},
+		})
+		defer sv.Shutdown(t, ctx)
 		kubeConfigFilename := kubeconfig.Create(t, &kubeconfig.Values{
-			Issuer:                  serverURL,
-			ExtraScopes:             "profile,groups",
-			IDPCertificateAuthority: idpTLS.CACertPath,
+			Issuer:      sv.IssuerURL(),
+			ExtraScopes: "profile,groups",
 		})
 		defer os.Remove(kubeConfigFilename)
-
-		args := []string{
-			"--kubeconfig", kubeConfigFilename,
-		}
-		runRootCmd(t, ctx, browserMock, args)
+		runStandalone(t, ctx, standaloneConfig{
+			issuerURL:          sv.IssuerURL(),
+			kubeConfigFilename: kubeConfigFilename,
+			httpDriver:         httpdriver.New(ctx, t, nil),
+			now:                now,
+		})
 		kubeconfig.Verify(t, kubeConfigFilename, kubeconfig.AuthProviderConfig{
-			IDToken:      idToken,
-			RefreshToken: "YOUR_REFRESH_TOKEN",
+			IDToken:      sv.LastTokenResponse().IDToken,
+			RefreshToken: sv.LastTokenResponse().RefreshToken,
 		})
 	})
 }
 
-func runRootCmd(t *testing.T, ctx context.Context, b browser.Interface, args []string) {
-	t.Helper()
-	cmd := di.NewCmdForHeadless(logger.New(t), b, nil)
+type standaloneConfig struct {
+	issuerURL          string
+	kubeConfigFilename string
+	httpDriver         browser.Interface
+	now                time.Time
+	args               []string
+}
+
+func runStandalone(t *testing.T, ctx context.Context, cfg standaloneConfig) {
+	cmd := di.NewCmdForHeadless(clock.Fake(cfg.now), os.Stdin, os.Stdout, logger.New(t), cfg.httpDriver)
 	exitCode := cmd.Run(ctx, append([]string{
 		"kubelogin",
-		"--v=1",
+		"--kubeconfig", cfg.kubeConfigFilename,
 		"--listen-address", "127.0.0.1:0",
-	}, args...), "HEAD")
+	}, cfg.args...), "HEAD")
 	if exitCode != 0 {
 		t.Errorf("exit status wants 0 but %d", exitCode)
 	}

pkg/adaptors/clock/clock.go

@@ -8,17 +8,17 @@ import (
 )
 
 var Set = wire.NewSet(
-	wire.Struct(new(Clock), "*"),
-	wire.Bind(new(Interface), new(*Clock)),
+	wire.Struct(new(Real), "*"),
+	wire.Bind(new(Interface), new(*Real)),
 )
 
 type Interface interface {
 	Now() time.Time
 }
 
-type Clock struct{}
+type Real struct{}
 
 // Now returns the current time.
-func (c *Clock) Now() time.Time {
+func (c *Real) Now() time.Time {
 	return time.Now()
 }

pkg/adaptors/cmd/cmd.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"context"
+	"runtime"
 
 	"github.com/google/wire"
 	"github.com/int128/kubelogin/pkg/adaptors/logger"
@@ -52,7 +53,7 @@ func (cmd *Cmd) Run(ctx context.Context, args []string, version string) int {
 		Short: "Print the version information",
 		Args:  cobra.NoArgs,
 		Run: func(*cobra.Command, []string) {
-			cmd.Logger.Printf("kubelogin version %s", version)
+			cmd.Logger.Printf("kubelogin version %s (%s %s_%s)", version, runtime.Version(), runtime.GOOS, runtime.GOARCH)
 		},
 	}
 	rootCmd.AddCommand(versionCmd)

pkg/adaptors/cmd/cmd_test.go

@@ -27,7 +27,8 @@ func TestCmd_Run(t *testing.T) {
 				in: standalone.Input{
 					GrantOptionSet: authentication.GrantOptionSet{
 						AuthCodeOption: &authentication.AuthCodeOption{
-							BindAddress: defaultListenAddress,
+							BindAddress:         defaultListenAddress,
+							RedirectURLHostname: "localhost",
 						},
 					},
 				},
@@ -41,7 +42,8 @@ func TestCmd_Run(t *testing.T) {
 				in: standalone.Input{
 					GrantOptionSet: authentication.GrantOptionSet{
 						AuthCodeOption: &authentication.AuthCodeOption{
-							BindAddress: []string{"127.0.0.1:10080", "127.0.0.1:20080"},
+							BindAddress:         []string{"127.0.0.1:10080", "127.0.0.1:20080"},
+							RedirectURLHostname: "localhost",
 						},
 					},
 				},
@@ -57,7 +59,8 @@ func TestCmd_Run(t *testing.T) {
 				in: standalone.Input{
 					GrantOptionSet: authentication.GrantOptionSet{
 						AuthCodeOption: &authentication.AuthCodeOption{
-							BindAddress: []string{"127.0.0.1:10080", "127.0.0.1:20080"},
+							BindAddress:         []string{"127.0.0.1:10080", "127.0.0.1:20080"},
+							RedirectURLHostname: "localhost",
 						},
 					},
 				},
@@ -85,8 +88,9 @@ func TestCmd_Run(t *testing.T) {
 					SkipTLSVerify:      true,
 					GrantOptionSet: authentication.GrantOptionSet{
 						AuthCodeOption: &authentication.AuthCodeOption{
-							BindAddress:     []string{"127.0.0.1:10080", "127.0.0.1:20080"},
-							SkipOpenBrowser: true,
+							BindAddress:         []string{"127.0.0.1:10080", "127.0.0.1:20080"},
+							SkipOpenBrowser:     true,
+							RedirectURLHostname: "localhost",
 						},
 					},
 				},
@@ -191,7 +195,8 @@ func TestCmd_Run(t *testing.T) {
 					ClientID:      "YOUR_CLIENT_ID",
 					GrantOptionSet: authentication.GrantOptionSet{
 						AuthCodeOption: &authentication.AuthCodeOption{
-							BindAddress: []string{"127.0.0.1:8000", "127.0.0.1:18000"},
+							BindAddress:         []string{"127.0.0.1:8000", "127.0.0.1:18000"},
+							RedirectURLHostname: "localhost",
 						},
 					},
 				},
@@ -230,6 +235,7 @@ func TestCmd_Run(t *testing.T) {
 						AuthCodeOption: &authentication.AuthCodeOption{
 							BindAddress:            []string{"127.0.0.1:10080", "127.0.0.1:20080"},
 							SkipOpenBrowser:        true,
+							RedirectURLHostname:    "localhost",
 							AuthRequestExtraParams: map[string]string{"ttl": "86400", "reauth": "true"},
 						},
 					},

pkg/adaptors/cmd/root.go

@@ -48,6 +48,7 @@ type authenticationOptions struct {
 	ListenAddress          []string
 	ListenPort             []int // deprecated
 	SkipOpenBrowser        bool
+	RedirectURLHostname    string
 	AuthRequestExtraParams map[string]string
 	Username               string
 	Password               string
@@ -81,6 +82,7 @@ func (o *authenticationOptions) register(f *pflag.FlagSet) {
 	//TODO: remove the deprecated flag
 	f.IntSliceVar(&o.ListenPort, "listen-port", nil, "(Deprecated: use --listen-address)")
 	f.BoolVar(&o.SkipOpenBrowser, "skip-open-browser", false, "If true, it does not open the browser on authentication")
+	f.StringVar(&o.RedirectURLHostname, "oidc-redirect-url-hostname", "localhost", "Hostname of the redirect URL")
 	f.StringToStringVar(&o.AuthRequestExtraParams, "oidc-auth-request-extra-params", nil, "Extra query parameters to send with an authentication request")
 	f.StringVar(&o.Username, "username", "", "If set, perform the resource owner password credentials grant")
 	f.StringVar(&o.Password, "password", "", "If set, use the password instead of asking it")
@@ -92,6 +94,7 @@ func (o *authenticationOptions) grantOptionSet() (s authentication.GrantOptionSe
 		s.AuthCodeOption = &authentication.AuthCodeOption{
 			BindAddress:            o.determineListenAddress(),
 			SkipOpenBrowser:        o.SkipOpenBrowser,
+			RedirectURLHostname:    o.RedirectURLHostname,
 			AuthRequestExtraParams: o.AuthRequestExtraParams,
 		}
 	case o.GrantType == "authcode-keyboard":

pkg/adaptors/credentialpluginwriter/credential_plugin.go

@@ -3,13 +3,13 @@ package credentialpluginwriter
 
 import (
 	"encoding/json"
-	"os"
 	"time"
 
 	"github.com/google/wire"
+	"github.com/int128/kubelogin/pkg/adaptors/stdio"
 	"golang.org/x/xerrors"
-	"k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/client-go/pkg/apis/clientauthentication/v1beta1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	clientauthenticationv1beta1 "k8s.io/client-go/pkg/apis/clientauthentication/v1beta1"
 )
 
 //go:generate mockgen -destination mock_credentialpluginwriter/mock_credentialpluginwriter.go github.com/int128/kubelogin/pkg/adaptors/credentialpluginwriter Interface
@@ -29,21 +29,23 @@ type Output struct {
 	Expiry time.Time
 }
 
-type Writer struct{}
+type Writer struct {
+	Stdout stdio.Stdout
+}
 
 // Write writes the ExecCredential to standard output for kubectl.
-func (*Writer) Write(out Output) error {
-	ec := &v1beta1.ExecCredential{
-		TypeMeta: v1.TypeMeta{
+func (w *Writer) Write(out Output) error {
+	ec := &clientauthenticationv1beta1.ExecCredential{
+		TypeMeta: metav1.TypeMeta{
 			APIVersion: "client.authentication.k8s.io/v1beta1",
 			Kind:       "ExecCredential",
 		},
-		Status: &v1beta1.ExecCredentialStatus{
+		Status: &clientauthenticationv1beta1.ExecCredentialStatus{
 			Token:               out.Token,
-			ExpirationTimestamp: &v1.Time{Time: out.Expiry},
+			ExpirationTimestamp: &metav1.Time{Time: out.Expiry},
 		},
 	}
-	e := json.NewEncoder(os.Stdout)
+	e := json.NewEncoder(w.Stdout)
 	if err := e.Encode(ec); err != nil {
 		return xerrors.Errorf("could not write the ExecCredential: %w", err)
 	}

pkg/adaptors/oidcclient/factory.go

@@ -4,17 +4,27 @@ package oidcclient
 import (
 	"context"
 	"crypto/tls"
+	"fmt"
 	"net/http"
 
 	"github.com/coreos/go-oidc"
+	"github.com/google/wire"
 	"github.com/int128/kubelogin/pkg/adaptors/certpool"
+	"github.com/int128/kubelogin/pkg/adaptors/clock"
 	"github.com/int128/kubelogin/pkg/adaptors/logger"
 	"github.com/int128/kubelogin/pkg/adaptors/oidcclient/logging"
 	"golang.org/x/oauth2"
 	"golang.org/x/xerrors"
 )
 
-type NewFunc func(ctx context.Context, config Config) (Interface, error)
+var Set = wire.NewSet(
+	wire.Struct(new(Factory), "*"),
+	wire.Bind(new(FactoryInterface), new(*Factory)),
+)
+
+type FactoryInterface interface {
+	New(ctx context.Context, config Config) (Interface, error)
+}
 
 // Config represents a configuration of OpenID Connect client.
 type Config struct {
@@ -24,11 +34,15 @@ type Config struct {
 	ExtraScopes   []string // optional
 	CertPool      certpool.Interface
 	SkipTLSVerify bool
-	Logger        logger.Interface
+}
+
+type Factory struct {
+	Clock  clock.Interface
+	Logger logger.Interface
 }
 
 // New returns an instance of adaptors.Interface with the given configuration.
-func New(ctx context.Context, config Config) (Interface, error) {
+func (f *Factory) New(ctx context.Context, config Config) (Interface, error) {
 	var tlsConfig tls.Config
 	tlsConfig.InsecureSkipVerify = config.SkipTLSVerify
 	config.CertPool.SetRootCAs(&tlsConfig)
@@ -38,7 +52,7 @@ func New(ctx context.Context, config Config) (Interface, error) {
 	}
 	loggingTransport := &logging.Transport{
 		Base:   baseTransport,
-		Logger: config.Logger,
+		Logger: f.Logger,
 	}
 	httpClient := &http.Client{
 		Transport: loggingTransport,
@@ -49,6 +63,10 @@ func New(ctx context.Context, config Config) (Interface, error) {
 	if err != nil {
 		return nil, xerrors.Errorf("oidc discovery error: %w", err)
 	}
+	supportedPKCEMethods, err := extractSupportedPKCEMethods(provider)
+	if err != nil {
+		return nil, xerrors.Errorf("could not determine supported PKCE methods: %w", err)
+	}
 	return &client{
 		httpClient: httpClient,
 		provider:   provider,
@@ -58,6 +76,18 @@ func New(ctx context.Context, config Config) (Interface, error) {
 			ClientSecret: config.ClientSecret,
 			Scopes:       append(config.ExtraScopes, oidc.ScopeOpenID),
 		},
-		logger: config.Logger,
+		clock:                f.Clock,
+		logger:               f.Logger,
+		supportedPKCEMethods: supportedPKCEMethods,
 	}, nil
 }
+
+func extractSupportedPKCEMethods(provider *oidc.Provider) ([]string, error) {
+	var d struct {
+		CodeChallengeMethodsSupported []string `json:"code_challenge_methods_supported"`
+	}
+	if err := provider.Claims(&d); err != nil {
+		return nil, fmt.Errorf("invalid discovery document: %w", err)
+	}
+	return d.CodeChallengeMethodsSupported, nil
+}

pkg/adaptors/oidcclient/mock_oidcclient/mock_oidcclient.go

@@ -11,30 +11,30 @@ import (
 	reflect "reflect"
 )
 
-// MockInterface is a mock of Interface interface
+// MockInterface is a mock of Interface interface.
 type MockInterface struct {
 	ctrl     *gomock.Controller
 	recorder *MockInterfaceMockRecorder
 }
 
-// MockInterfaceMockRecorder is the mock recorder for MockInterface
+// MockInterfaceMockRecorder is the mock recorder for MockInterface.
 type MockInterfaceMockRecorder struct {
 	mock *MockInterface
 }
 
-// NewMockInterface creates a new mock instance
+// NewMockInterface creates a new mock instance.
 func NewMockInterface(ctrl *gomock.Controller) *MockInterface {
 	mock := &MockInterface{ctrl: ctrl}
 	mock.recorder = &MockInterfaceMockRecorder{mock}
 	return mock
 }
 
-// EXPECT returns an object that allows the caller to indicate expected use
+// EXPECT returns an object that allows the caller to indicate expected use.
 func (m *MockInterface) EXPECT() *MockInterfaceMockRecorder {
 	return m.recorder
 }
 
-// ExchangeAuthCode mocks base method
+// ExchangeAuthCode mocks base method.
 func (m *MockInterface) ExchangeAuthCode(arg0 context.Context, arg1 oidcclient.ExchangeAuthCodeInput) (*oidcclient.TokenSet, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "ExchangeAuthCode", arg0, arg1)
@@ -43,13 +43,13 @@ func (m *MockInterface) ExchangeAuthCode(arg0 context.Context, arg1 oidcclient.E
 	return ret0, ret1
 }
 
-// ExchangeAuthCode indicates an expected call of ExchangeAuthCode
+// ExchangeAuthCode indicates an expected call of ExchangeAuthCode.
 func (mr *MockInterfaceMockRecorder) ExchangeAuthCode(arg0, arg1 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ExchangeAuthCode", reflect.TypeOf((*MockInterface)(nil).ExchangeAuthCode), arg0, arg1)
 }
 
-// GetAuthCodeURL mocks base method
+// GetAuthCodeURL mocks base method.
 func (m *MockInterface) GetAuthCodeURL(arg0 oidcclient.AuthCodeURLInput) string {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "GetAuthCodeURL", arg0)
@@ -57,13 +57,13 @@ func (m *MockInterface) GetAuthCodeURL(arg0 oidcclient.AuthCodeURLInput) string
 	return ret0
 }
 
-// GetAuthCodeURL indicates an expected call of GetAuthCodeURL
+// GetAuthCodeURL indicates an expected call of GetAuthCodeURL.
 func (mr *MockInterfaceMockRecorder) GetAuthCodeURL(arg0 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetAuthCodeURL", reflect.TypeOf((*MockInterface)(nil).GetAuthCodeURL), arg0)
 }
 
-// GetTokenByAuthCode mocks base method
+// GetTokenByAuthCode mocks base method.
 func (m *MockInterface) GetTokenByAuthCode(arg0 context.Context, arg1 oidcclient.GetTokenByAuthCodeInput, arg2 chan<- string) (*oidcclient.TokenSet, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "GetTokenByAuthCode", arg0, arg1, arg2)
@@ -72,13 +72,13 @@ func (m *MockInterface) GetTokenByAuthCode(arg0 context.Context, arg1 oidcclient
 	return ret0, ret1
 }
 
-// GetTokenByAuthCode indicates an expected call of GetTokenByAuthCode
+// GetTokenByAuthCode indicates an expected call of GetTokenByAuthCode.
 func (mr *MockInterfaceMockRecorder) GetTokenByAuthCode(arg0, arg1, arg2 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetTokenByAuthCode", reflect.TypeOf((*MockInterface)(nil).GetTokenByAuthCode), arg0, arg1, arg2)
 }
 
-// GetTokenByROPC mocks base method
+// GetTokenByROPC mocks base method.
 func (m *MockInterface) GetTokenByROPC(arg0 context.Context, arg1, arg2 string) (*oidcclient.TokenSet, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "GetTokenByROPC", arg0, arg1, arg2)
@@ -87,13 +87,13 @@ func (m *MockInterface) GetTokenByROPC(arg0 context.Context, arg1, arg2 string)
 	return ret0, ret1
 }
 
-// GetTokenByROPC indicates an expected call of GetTokenByROPC
+// GetTokenByROPC indicates an expected call of GetTokenByROPC.
 func (mr *MockInterfaceMockRecorder) GetTokenByROPC(arg0, arg1, arg2 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetTokenByROPC", reflect.TypeOf((*MockInterface)(nil).GetTokenByROPC), arg0, arg1, arg2)
 }
 
-// Refresh mocks base method
+// Refresh mocks base method.
 func (m *MockInterface) Refresh(arg0 context.Context, arg1 string) (*oidcclient.TokenSet, error) {
 	m.ctrl.T.Helper()
 	ret := m.ctrl.Call(m, "Refresh", arg0, arg1)
@@ -102,8 +102,22 @@ func (m *MockInterface) Refresh(arg0 context.Context, arg1 string) (*oidcclient.
 	return ret0, ret1
 }
 
-// Refresh indicates an expected call of Refresh
+// Refresh indicates an expected call of Refresh.
 func (mr *MockInterfaceMockRecorder) Refresh(arg0, arg1 interface{}) *gomock.Call {
 	mr.mock.ctrl.T.Helper()
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "Refresh", reflect.TypeOf((*MockInterface)(nil).Refresh), arg0, arg1)
 }
+
+// SupportedPKCEMethods mocks base method.
+func (m *MockInterface) SupportedPKCEMethods() []string {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "SupportedPKCEMethods")
+	ret0, _ := ret[0].([]string)
+	return ret0
+}
+
+// SupportedPKCEMethods indicates an expected call of SupportedPKCEMethods.
+func (mr *MockInterfaceMockRecorder) SupportedPKCEMethods() *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "SupportedPKCEMethods", reflect.TypeOf((*MockInterface)(nil).SupportedPKCEMethods))
+}

pkg/adaptors/oidcclient/oidcclient.go

@@ -6,9 +6,10 @@ import (
 	"time"
 
 	"github.com/coreos/go-oidc"
-	"github.com/google/wire"
+	"github.com/int128/kubelogin/pkg/adaptors/clock"
 	"github.com/int128/kubelogin/pkg/adaptors/logger"
 	"github.com/int128/kubelogin/pkg/domain/jwt"
+	"github.com/int128/kubelogin/pkg/domain/pkce"
 	"github.com/int128/oauth2cli"
 	"golang.org/x/oauth2"
 	"golang.org/x/xerrors"
@@ -16,42 +17,38 @@ import (
 
 //go:generate mockgen -destination mock_oidcclient/mock_oidcclient.go github.com/int128/kubelogin/pkg/adaptors/oidcclient Interface
 
-var Set = wire.NewSet(
-	wire.Value(NewFunc(New)),
-)
-
 type Interface interface {
 	GetAuthCodeURL(in AuthCodeURLInput) string
 	ExchangeAuthCode(ctx context.Context, in ExchangeAuthCodeInput) (*TokenSet, error)
 	GetTokenByAuthCode(ctx context.Context, in GetTokenByAuthCodeInput, localServerReadyChan chan<- string) (*TokenSet, error)
 	GetTokenByROPC(ctx context.Context, username, password string) (*TokenSet, error)
 	Refresh(ctx context.Context, refreshToken string) (*TokenSet, error)
+	SupportedPKCEMethods() []string
 }
 
 type AuthCodeURLInput struct {
 	State                  string
 	Nonce                  string
-	CodeChallenge          string
-	CodeChallengeMethod    string
+	PKCEParams             pkce.Params
 	RedirectURI            string
 	AuthRequestExtraParams map[string]string
 }
 
 type ExchangeAuthCodeInput struct {
-	Code         string
-	CodeVerifier string
-	Nonce        string
-	RedirectURI  string
+	Code        string
+	PKCEParams  pkce.Params
+	Nonce       string
+	RedirectURI string
 }
 
 type GetTokenByAuthCodeInput struct {
 	BindAddress            []string
 	State                  string
 	Nonce                  string
-	CodeChallenge          string
-	CodeChallengeMethod    string
-	CodeVerifier           string
+	PKCEParams             pkce.Params
+	RedirectURLHostname    string
 	AuthRequestExtraParams map[string]string
+	LocalServerSuccessHTML string
 }
 
 // TokenSet represents an output DTO of
@@ -63,10 +60,12 @@ type TokenSet struct {
 }
 
 type client struct {
-	httpClient   *http.Client
-	provider     *oidc.Provider
-	oauth2Config oauth2.Config
-	logger       logger.Interface
+	httpClient           *http.Client
+	provider             *oidc.Provider
+	oauth2Config         oauth2.Config
+	clock                clock.Interface
+	logger               logger.Interface
+	supportedPKCEMethods []string
 }
 
 func (c *client) wrapContext(ctx context.Context) context.Context {
@@ -80,24 +79,16 @@ func (c *client) wrapContext(ctx context.Context) context.Context {
 func (c *client) GetTokenByAuthCode(ctx context.Context, in GetTokenByAuthCodeInput, localServerReadyChan chan<- string) (*TokenSet, error) {
 	ctx = c.wrapContext(ctx)
 	config := oauth2cli.Config{
-		OAuth2Config: c.oauth2Config,
-		State:        in.State,
-		AuthCodeOptions: []oauth2.AuthCodeOption{
-			oauth2.AccessTypeOffline,
-			oidc.Nonce(in.Nonce),
-			oauth2.SetAuthURLParam("code_challenge", in.CodeChallenge),
-			oauth2.SetAuthURLParam("code_challenge_method", in.CodeChallengeMethod),
-		},
-		TokenRequestOptions: []oauth2.AuthCodeOption{
-			oauth2.SetAuthURLParam("code_verifier", in.CodeVerifier),
-		},
+		OAuth2Config:           c.oauth2Config,
+		State:                  in.State,
+		AuthCodeOptions:        authorizationRequestOptions(in.Nonce, in.PKCEParams, in.AuthRequestExtraParams),
+		TokenRequestOptions:    tokenRequestOptions(in.PKCEParams),
 		LocalServerBindAddress: in.BindAddress,
 		LocalServerReadyChan:   localServerReadyChan,
+		RedirectURLHostname:    in.RedirectURLHostname,
+		LocalServerSuccessHTML: in.LocalServerSuccessHTML,
+		Logf:                   c.logger.V(1).Infof,
 	}
-	for key, value := range in.AuthRequestExtraParams {
-		config.AuthCodeOptions = append(config.AuthCodeOptions, oauth2.SetAuthURLParam(key, value))
-	}
-
 	token, err := oauth2cli.GetToken(ctx, config)
 	if err != nil {
 		return nil, xerrors.Errorf("oauth2 error: %w", err)
@@ -109,15 +100,7 @@ func (c *client) GetTokenByAuthCode(ctx context.Context, in GetTokenByAuthCodeIn
 func (c *client) GetAuthCodeURL(in AuthCodeURLInput) string {
 	cfg := c.oauth2Config
 	cfg.RedirectURL = in.RedirectURI
-	opts := []oauth2.AuthCodeOption{
-		oauth2.AccessTypeOffline,
-		oidc.Nonce(in.Nonce),
-		oauth2.SetAuthURLParam("code_challenge", in.CodeChallenge),
-		oauth2.SetAuthURLParam("code_challenge_method", in.CodeChallengeMethod),
-	}
-	for key, value := range in.AuthRequestExtraParams {
-		opts = append(opts, oauth2.SetAuthURLParam(key, value))
-	}
+	opts := authorizationRequestOptions(in.Nonce, in.PKCEParams, in.AuthRequestExtraParams)
 	return cfg.AuthCodeURL(in.State, opts...)
 }
 
@@ -126,13 +109,44 @@ func (c *client) ExchangeAuthCode(ctx context.Context, in ExchangeAuthCodeInput)
 	ctx = c.wrapContext(ctx)
 	cfg := c.oauth2Config
 	cfg.RedirectURL = in.RedirectURI
-	token, err := cfg.Exchange(ctx, in.Code, oauth2.SetAuthURLParam("code_verifier", in.CodeVerifier))
+	opts := tokenRequestOptions(in.PKCEParams)
+	token, err := cfg.Exchange(ctx, in.Code, opts...)
 	if err != nil {
 		return nil, xerrors.Errorf("exchange error: %w", err)
 	}
 	return c.verifyToken(ctx, token, in.Nonce)
 }
 
+func authorizationRequestOptions(n string, p pkce.Params, e map[string]string) []oauth2.AuthCodeOption {
+	o := []oauth2.AuthCodeOption{
+		oauth2.AccessTypeOffline,
+		oidc.Nonce(n),
+	}
+	if !p.IsZero() {
+		o = append(o,
+			oauth2.SetAuthURLParam("code_challenge", p.CodeChallenge),
+			oauth2.SetAuthURLParam("code_challenge_method", p.CodeChallengeMethod),
+		)
+	}
+	for key, value := range e {
+		o = append(o, oauth2.SetAuthURLParam(key, value))
+	}
+	return o
+}
+
+func tokenRequestOptions(p pkce.Params) (o []oauth2.AuthCodeOption) {
+	if !p.IsZero() {
+		o = append(o, oauth2.SetAuthURLParam("code_verifier", p.CodeVerifier))
+	}
+	return
+}
+
+// SupportedPKCEMethods returns the PKCE methods supported by the provider.
+// This may return nil if PKCE is not supported.
+func (c *client) SupportedPKCEMethods() []string {
+	return c.supportedPKCEMethods
+}
+
 // GetTokenByROPC performs the resource owner password credentials flow.
 func (c *client) GetTokenByROPC(ctx context.Context, username, password string) (*TokenSet, error) {
 	ctx = c.wrapContext(ctx)
@@ -165,7 +179,7 @@ func (c *client) verifyToken(ctx context.Context, token *oauth2.Token, nonce str
 	if !ok {
 		return nil, xerrors.Errorf("id_token is missing in the token response: %s", token)
 	}
-	verifier := c.provider.Verifier(&oidc.Config{ClientID: c.oauth2Config.ClientID})
+	verifier := c.provider.Verifier(&oidc.Config{ClientID: c.oauth2Config.ClientID, Now: c.clock.Now})
 	verifiedIDToken, err := verifier.Verify(ctx, idToken)
 	if err != nil {
 		return nil, xerrors.Errorf("could not verify the ID token: %w", err)

pkg/adaptors/reader/reader.go

@@ -9,6 +9,7 @@ import (
 	"syscall"
 
 	"github.com/google/wire"
+	"github.com/int128/kubelogin/pkg/adaptors/stdio"
 	"golang.org/x/crypto/ssh/terminal"
 	"golang.org/x/xerrors"
 )
@@ -26,14 +27,16 @@ type Interface interface {
 	ReadPassword(prompt string) (string, error)
 }
 
-type Reader struct{}
+type Reader struct {
+	Stdin stdio.Stdin
+}
 
 // ReadString reads a string from the stdin.
-func (*Reader) ReadString(prompt string) (string, error) {
+func (x *Reader) ReadString(prompt string) (string, error) {
 	if _, err := fmt.Fprint(os.Stderr, prompt); err != nil {
 		return "", xerrors.Errorf("write error: %w", err)
 	}
-	r := bufio.NewReader(os.Stdin)
+	r := bufio.NewReader(x.Stdin)
 	s, err := r.ReadString('\n')
 	if err != nil {
 		return "", xerrors.Errorf("read error: %w", err)

pkg/adaptors/stdio/stdio.go

@@ -0,0 +1,17 @@
+// Package stdio wraps os.Stdin and os.Stdout for testing.
+package stdio
+
+import (
+	"io"
+	"os"
+
+	"github.com/google/wire"
+)
+
+var Set = wire.NewSet(
+	wire.InterfaceValue(new(Stdin), os.Stdin),
+	wire.InterfaceValue(new(Stdout), os.Stdout),
+)
+
+type Stdout io.Writer
+type Stdin io.Reader

pkg/di/di.go

@@ -14,6 +14,7 @@ import (
 	"github.com/int128/kubelogin/pkg/adaptors/logger"
 	"github.com/int128/kubelogin/pkg/adaptors/oidcclient"
 	"github.com/int128/kubelogin/pkg/adaptors/reader"
+	"github.com/int128/kubelogin/pkg/adaptors/stdio"
 	"github.com/int128/kubelogin/pkg/adaptors/tokencache"
 	"github.com/int128/kubelogin/pkg/usecases/authentication"
 	"github.com/int128/kubelogin/pkg/usecases/credentialplugin"
@@ -27,15 +28,16 @@ func NewCmd() cmd.Interface {
 		NewCmdForHeadless,
 
 		// dependencies for production
+		clock.Set,
+		stdio.Set,
 		logger.Set,
 		browser.Set,
-		credentialpluginwriter.Set,
 	)
 	return nil
 }
 
 // NewCmdForHeadless returns an instance of adaptors.Cmd for headless testing.
-func NewCmdForHeadless(logger.Interface, browser.Interface, credentialpluginwriter.Interface) cmd.Interface {
+func NewCmdForHeadless(clock.Interface, stdio.Stdin, stdio.Stdout, logger.Interface, browser.Interface) cmd.Interface {
 	wire.Build(
 		// use-cases
 		authentication.Set,
@@ -46,11 +48,11 @@ func NewCmdForHeadless(logger.Interface, browser.Interface, credentialpluginwrit
 		// adaptors
 		cmd.Set,
 		reader.Set,
-		clock.Set,
 		kubeconfig.Set,
 		tokencache.Set,
 		oidcclient.Set,
 		certpool.Set,
+		credentialpluginwriter.Set,
 	)
 	return nil
 }

pkg/di/wire_gen.go

@@ -15,31 +15,44 @@ import (
 	"github.com/int128/kubelogin/pkg/adaptors/logger"
 	"github.com/int128/kubelogin/pkg/adaptors/oidcclient"
 	"github.com/int128/kubelogin/pkg/adaptors/reader"
+	"github.com/int128/kubelogin/pkg/adaptors/stdio"
 	"github.com/int128/kubelogin/pkg/adaptors/tokencache"
 	"github.com/int128/kubelogin/pkg/usecases/authentication"
 	"github.com/int128/kubelogin/pkg/usecases/credentialplugin"
 	"github.com/int128/kubelogin/pkg/usecases/setup"
 	"github.com/int128/kubelogin/pkg/usecases/standalone"
+	"os"
 )
 
 // Injectors from di.go:
 
 func NewCmd() cmd.Interface {
+	clockReal := &clock.Real{}
+	stdin := _wireFileValue
+	stdout := _wireOsFileValue
 	loggerInterface := logger.New()
 	browserBrowser := &browser.Browser{}
-	writer := &credentialpluginwriter.Writer{}
-	cmdInterface := NewCmdForHeadless(loggerInterface, browserBrowser, writer)
+	cmdInterface := NewCmdForHeadless(clockReal, stdin, stdout, loggerInterface, browserBrowser)
 	return cmdInterface
 }
 
-func NewCmdForHeadless(loggerInterface logger.Interface, browserInterface browser.Interface, credentialpluginwriterInterface credentialpluginwriter.Interface) cmd.Interface {
-	newFunc := _wireNewFuncValue
-	clockClock := &clock.Clock{}
+var (
+	_wireFileValue   = os.Stdin
+	_wireOsFileValue = os.Stdout
+)
+
+func NewCmdForHeadless(clockInterface clock.Interface, stdin stdio.Stdin, stdout stdio.Stdout, loggerInterface logger.Interface, browserInterface browser.Interface) cmd.Interface {
+	factory := &oidcclient.Factory{
+		Clock:  clockInterface,
+		Logger: loggerInterface,
+	}
 	authCode := &authentication.AuthCode{
 		Browser: browserInterface,
 		Logger:  loggerInterface,
 	}
-	readerReader := &reader.Reader{}
+	readerReader := &reader.Reader{
+		Stdin: stdin,
+	}
 	authCodeKeyboard := &authentication.AuthCodeKeyboard{
 		Reader: readerReader,
 		Logger: loggerInterface,
@@ -49,9 +62,9 @@ func NewCmdForHeadless(loggerInterface logger.Interface, browserInterface browse
 		Logger: loggerInterface,
 	}
 	authenticationAuthentication := &authentication.Authentication{
-		NewOIDCClient:    newFunc,
+		OIDCClient:       factory,
 		Logger:           loggerInterface,
-		Clock:            clockClock,
+		Clock:            clockInterface,
 		AuthCode:         authCode,
 		AuthCodeKeyboard: authCodeKeyboard,
 		ROPC:             ropc,
@@ -59,11 +72,11 @@ func NewCmdForHeadless(loggerInterface logger.Interface, browserInterface browse
 	kubeconfigKubeconfig := &kubeconfig.Kubeconfig{
 		Logger: loggerInterface,
 	}
-	certpoolNewFunc := _wireCertpoolNewFuncValue
+	newFunc := _wireNewFuncValue
 	standaloneStandalone := &standalone.Standalone{
 		Authentication: authenticationAuthentication,
 		Kubeconfig:     kubeconfigKubeconfig,
-		NewCertPool:    certpoolNewFunc,
+		NewCertPool:    newFunc,
 		Logger:         loggerInterface,
 	}
 	root := &cmd.Root{
@@ -71,11 +84,14 @@ func NewCmdForHeadless(loggerInterface logger.Interface, browserInterface browse
 		Logger:     loggerInterface,
 	}
 	repository := &tokencache.Repository{}
+	writer := &credentialpluginwriter.Writer{
+		Stdout: stdout,
+	}
 	getToken := &credentialplugin.GetToken{
 		Authentication:       authenticationAuthentication,
 		TokenCacheRepository: repository,
-		NewCertPool:          certpoolNewFunc,
-		Writer:               credentialpluginwriterInterface,
+		NewCertPool:          newFunc,
+		Writer:               writer,
 		Logger:               loggerInterface,
 	}
 	cmdGetToken := &cmd.GetToken{
@@ -84,7 +100,7 @@ func NewCmdForHeadless(loggerInterface logger.Interface, browserInterface browse
 	}
 	setupSetup := &setup.Setup{
 		Authentication: authenticationAuthentication,
-		NewCertPool:    certpoolNewFunc,
+		NewCertPool:    newFunc,
 		Logger:         loggerInterface,
 	}
 	cmdSetup := &cmd.Setup{
@@ -100,6 +116,5 @@ func NewCmdForHeadless(loggerInterface logger.Interface, browserInterface browse
 }
 
 var (
-	_wireNewFuncValue         = oidcclient.NewFunc(oidcclient.New)
-	_wireCertpoolNewFuncValue = certpool.NewFunc(certpool.New)
+	_wireNewFuncValue = certpool.NewFunc(certpool.New)
 )

pkg/domain/oidc/oidc.go

@@ -2,7 +2,6 @@ package oidc
 
 import (
 	"crypto/rand"
-	"crypto/sha256"
 	"encoding/base64"
 	"encoding/binary"
 
@@ -25,21 +24,6 @@ func NewNonce() (string, error) {
 	return base64URLEncode(b), nil
 }
 
-type PKCEParams struct {
-	CodeChallenge       string
-	CodeChallengeMethod string
-	CodeVerifier        string
-}
-
-func NewPKCEParams() (*PKCEParams, error) {
-	b, err := random32()
-	if err != nil {
-		return nil, xerrors.Errorf("could not generate a random: %w", err)
-	}
-	s := computeS256(b)
-	return &s, nil
-}
-
 func random32() ([]byte, error) {
 	b := make([]byte, 32)
 	if err := binary.Read(rand.Reader, binary.LittleEndian, b); err != nil {
@@ -48,17 +32,6 @@ func random32() ([]byte, error) {
 	return b, nil
 }
 
-func computeS256(b []byte) PKCEParams {
-	v := base64URLEncode(b)
-	s := sha256.New()
-	_, _ = s.Write([]byte(v))
-	return PKCEParams{
-		CodeChallenge:       base64URLEncode(s.Sum(nil)),
-		CodeChallengeMethod: "S256",
-		CodeVerifier:        v,
-	}
-}
-
 func base64URLEncode(b []byte) string {
 	return base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString(b)
 }

pkg/domain/oidc/oidc_test.go

@@ -1,25 +0,0 @@
-package oidc
-
-import (
-	"testing"
-)
-
-func Test_computeS256(t *testing.T) {
-	// Testdata described at:
-	// https://tools.ietf.org/html/rfc7636#appendix-B
-	b := []byte{
-		116, 24, 223, 180, 151, 153, 224, 37, 79, 250, 96, 125, 216, 173,
-		187, 186, 22, 212, 37, 77, 105, 214, 191, 240, 91, 88, 5, 88, 83,
-		132, 141, 121,
-	}
-	p := computeS256(b)
-	if want := "dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"; want != p.CodeVerifier {
-		t.Errorf("CodeVerifier wants %s but was %s", want, p.CodeVerifier)
-	}
-	if want := "E9Melhoa2OwvFrEMTJguCHaoeK1t8URWbuGJSstw-cM"; want != p.CodeChallenge {
-		t.Errorf("CodeChallenge wants %s but was %s", want, p.CodeChallenge)
-	}
-	if p.CodeChallengeMethod != "S256" {
-		t.Errorf("CodeChallengeMethod wants S256 but was %s", p.CodeChallengeMethod)
-	}
-}

pkg/domain/pkce/pkce.go

@@ -0,0 +1,74 @@
+// Package pkce provides generation of the PKCE parameters.
+// See also https://tools.ietf.org/html/rfc7636.
+package pkce
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/binary"
+
+	"golang.org/x/xerrors"
+)
+
+var Plain Params
+
+const (
+	// code challenge methods defined as https://tools.ietf.org/html/rfc7636#section-4.3
+	methodS256 = "S256"
+)
+
+// Params represents a set of the PKCE parameters.
+type Params struct {
+	CodeChallenge       string
+	CodeChallengeMethod string
+	CodeVerifier        string
+}
+
+func (p Params) IsZero() bool {
+	return p == Params{}
+}
+
+// New returns a parameters supported by the provider.
+// You need to pass the code challenge methods defined in RFC7636.
+// It returns Plain if no method is available.
+func New(methods []string) (Params, error) {
+	for _, method := range methods {
+		if method == methodS256 {
+			return NewS256()
+		}
+	}
+	return Plain, nil
+}
+
+// NewS256 generates a parameters for S256.
+func NewS256() (Params, error) {
+	b, err := random32()
+	if err != nil {
+		return Plain, xerrors.Errorf("could not generate a random: %w", err)
+	}
+	return computeS256(b), nil
+}
+
+func random32() ([]byte, error) {
+	b := make([]byte, 32)
+	if err := binary.Read(rand.Reader, binary.LittleEndian, b); err != nil {
+		return nil, xerrors.Errorf("read error: %w", err)
+	}
+	return b, nil
+}
+
+func computeS256(b []byte) Params {
+	v := base64URLEncode(b)
+	s := sha256.New()
+	_, _ = s.Write([]byte(v))
+	return Params{
+		CodeChallenge:       base64URLEncode(s.Sum(nil)),
+		CodeChallengeMethod: methodS256,
+		CodeVerifier:        v,
+	}
+}
+
+func base64URLEncode(b []byte) string {
+	return base64.URLEncoding.WithPadding(base64.NoPadding).EncodeToString(b)
+}

pkg/domain/pkce/pkce_test.go

@@ -0,0 +1,61 @@
+package pkce
+
+import (
+	"testing"
+)
+
+func TestNew(t *testing.T) {
+	t.Run("S256", func(t *testing.T) {
+		p, err := New([]string{"plain", "S256"})
+		if err != nil {
+			t.Fatalf("New error: %s", err)
+		}
+		if p.CodeChallengeMethod != "S256" {
+			t.Errorf("CodeChallengeMethod wants S256 but was %s", p.CodeChallengeMethod)
+		}
+		if p.CodeChallenge == "" {
+			t.Errorf("CodeChallenge wants non-empty but was empty")
+		}
+		if p.CodeVerifier == "" {
+			t.Errorf("CodeVerifier wants non-empty but was empty")
+		}
+	})
+	t.Run("plain", func(t *testing.T) {
+		p, err := New([]string{"plain"})
+		if err != nil {
+			t.Fatalf("New error: %s", err)
+		}
+		if !p.IsZero() {
+			t.Errorf("IsZero wants true but was false")
+		}
+	})
+	t.Run("nil", func(t *testing.T) {
+		p, err := New(nil)
+		if err != nil {
+			t.Fatalf("New error: %s", err)
+		}
+		if !p.IsZero() {
+			t.Errorf("IsZero wants true but was false")
+		}
+	})
+}
+
+func Test_computeS256(t *testing.T) {
+	// Testdata described at:
+	// https://tools.ietf.org/html/rfc7636#appendix-B
+	b := []byte{
+		116, 24, 223, 180, 151, 153, 224, 37, 79, 250, 96, 125, 216, 173,
+		187, 186, 22, 212, 37, 77, 105, 214, 191, 240, 91, 88, 5, 88, 83,
+		132, 141, 121,
+	}
+	p := computeS256(b)
+	if want := "dBjftJeZ4CVP-mB92K27uhbUJU1p1r_wW1gFWFOEjXk"; want != p.CodeVerifier {
+		t.Errorf("CodeVerifier wants %s but was %s", want, p.CodeVerifier)
+	}
+	if want := "E9Melhoa2OwvFrEMTJguCHaoeK1t8URWbuGJSstw-cM"; want != p.CodeChallenge {
+		t.Errorf("CodeChallenge wants %s but was %s", want, p.CodeChallenge)
+	}
+	if p.CodeChallengeMethod != "S256" {
+		t.Errorf("CodeChallengeMethod wants S256 but was %s", p.CodeChallengeMethod)
+	}
+}

pkg/templates/authcode_browser.go

@@ -0,0 +1,35 @@
+package templates
+
+// AuthCodeBrowserSuccessHTML is the success page on browser based authentication.
+const AuthCodeBrowserSuccessHTML = `
+<!DOCTYPE html>
+<html lang="en">
+<head>
+	<meta charset="UTF-8">
+	<title>Authenticated</title>
+	<script>
+		window.close()
+	</script>
+	<style>
+		body {
+			background-color: #eee;
+			margin: 0;
+			padding: 0;
+			font-family: sans-serif;
+		}
+		.placeholder {
+			margin: 2em;
+			padding: 2em;
+			background-color: #fff;
+			border-radius: 1em;
+		}
+	</style>
+</head>
+<body>
+	<div class="placeholder">
+		<h1>Authenticated</h1>
+		<p>You have logged in to the cluster. You can close this window.</p>
+	</div>
+</body>
+</html>
+`

pkg/templates/httpserver/httpserver.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+	"log"
+	"net/http"
+
+	"github.com/int128/kubelogin/pkg/templates"
+)
+
+func main() {
+	http.HandleFunc("/AuthCodeBrowserSuccessHTML", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Add("content-type", "text/html")
+		_, _ = w.Write([]byte(templates.AuthCodeBrowserSuccessHTML))
+	})
+	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Add("content-type", "text/html")
+		_, _ = w.Write([]byte(`
+<html>
+<body>
+<ul>
+<li><a href="AuthCodeBrowserSuccessHTML">AuthCodeBrowserSuccessHTML</a></li>
+</ul>
+</body>
+</html>
+`))
+	})
+	log.Printf("http://localhost:8000")
+	log.Fatal(http.ListenAndServe("127.0.0.1:8000", nil))
+}

pkg/templates/package.go

@@ -0,0 +1,6 @@
+// Package templates provides templates such as HTML and messages.
+//
+// You can preview HTML pages by running httpserver package.
+//	go run ./httpserver
+//
+package templates

pkg/usecases/authentication/authcode_browser.go

@@ -7,6 +7,8 @@ import (
 	"github.com/int128/kubelogin/pkg/adaptors/logger"
 	"github.com/int128/kubelogin/pkg/adaptors/oidcclient"
 	"github.com/int128/kubelogin/pkg/domain/oidc"
+	"github.com/int128/kubelogin/pkg/domain/pkce"
+	"github.com/int128/kubelogin/pkg/templates"
 	"golang.org/x/sync/errgroup"
 	"golang.org/x/xerrors"
 )
@@ -18,7 +20,7 @@ type AuthCode struct {
 }
 
 func (u *AuthCode) Do(ctx context.Context, o *AuthCodeOption, client oidcclient.Interface) (*Output, error) {
-	u.Logger.V(1).Infof("performing the authentication code flow")
+	u.Logger.V(1).Infof("starting the authentication code flow via the browser")
 	state, err := oidc.NewState()
 	if err != nil {
 		return nil, xerrors.Errorf("could not generate a state: %w", err)
@@ -27,7 +29,7 @@ func (u *AuthCode) Do(ctx context.Context, o *AuthCodeOption, client oidcclient.
 	if err != nil {
 		return nil, xerrors.Errorf("could not generate a nonce: %w", err)
 	}
-	p, err := oidc.NewPKCEParams()
+	p, err := pkce.New(client.SupportedPKCEMethods())
 	if err != nil {
 		return nil, xerrors.Errorf("could not generate PKCE parameters: %w", err)
 	}
@@ -35,10 +37,10 @@ func (u *AuthCode) Do(ctx context.Context, o *AuthCodeOption, client oidcclient.
 		BindAddress:            o.BindAddress,
 		State:                  state,
 		Nonce:                  nonce,
-		CodeChallenge:          p.CodeChallenge,
-		CodeChallengeMethod:    p.CodeChallengeMethod,
-		CodeVerifier:           p.CodeVerifier,
+		PKCEParams:             p,
+		RedirectURLHostname:    o.RedirectURLHostname,
 		AuthRequestExtraParams: o.AuthRequestExtraParams,
+		LocalServerSuccessHTML: templates.AuthCodeBrowserSuccessHTML,
 	}
 	readyChan := make(chan string, 1)
 	defer close(readyChan)
@@ -54,6 +56,7 @@ func (u *AuthCode) Do(ctx context.Context, o *AuthCodeOption, client oidcclient.
 				u.Logger.Printf("Please visit the following URL in your browser: %s", url)
 				return nil
 			}
+			u.Logger.V(1).Infof("opening %s in the browser", url)
 			if err := u.Browser.Open(url); err != nil {
 				u.Logger.Printf(`error: could not open the browser: %s
 
@@ -75,10 +78,12 @@ Please visit the following URL in your browser manually: %s`, err, url)
 			IDTokenClaims: tokenSet.IDTokenClaims,
 			RefreshToken:  tokenSet.RefreshToken,
 		}
+		u.Logger.V(1).Infof("got a token set by the authorization code flow")
 		return nil
 	})
 	if err := eg.Wait(); err != nil {
 		return nil, xerrors.Errorf("authentication error: %w", err)
 	}
+	u.Logger.V(1).Infof("finished the authorization code flow via the browser")
 	return &out, nil
 }

pkg/usecases/authentication/authcode_browser_test.go

@@ -30,15 +30,20 @@ func TestAuthCode_Do(t *testing.T) {
 		o := &AuthCodeOption{
 			BindAddress:            []string{"127.0.0.1:8000"},
 			SkipOpenBrowser:        true,
+			RedirectURLHostname:    "localhost",
 			AuthRequestExtraParams: map[string]string{"ttl": "86400", "reauth": "true"},
 		}
 		mockOIDCClient := mock_oidcclient.NewMockInterface(ctrl)
+		mockOIDCClient.EXPECT().SupportedPKCEMethods()
 		mockOIDCClient.EXPECT().
 			GetTokenByAuthCode(gomock.Any(), gomock.Any(), gomock.Any()).
 			Do(func(_ context.Context, in oidcclient.GetTokenByAuthCodeInput, readyChan chan<- string) {
 				if diff := cmp.Diff(o.BindAddress, in.BindAddress); diff != "" {
 					t.Errorf("BindAddress mismatch (-want +got):\n%s", diff)
 				}
+				if diff := cmp.Diff(o.RedirectURLHostname, in.RedirectURLHostname); diff != "" {
+					t.Errorf("RedirectURLHostname mismatch (-want +got):\n%s", diff)
+				}
 				if diff := cmp.Diff(o.AuthRequestExtraParams, in.AuthRequestExtraParams); diff != "" {
 					t.Errorf("AuthRequestExtraParams mismatch (-want +got):\n%s", diff)
 				}
@@ -75,6 +80,7 @@ func TestAuthCode_Do(t *testing.T) {
 			BindAddress: []string{"127.0.0.1:8000"},
 		}
 		mockOIDCClient := mock_oidcclient.NewMockInterface(ctrl)
+		mockOIDCClient.EXPECT().SupportedPKCEMethods()
 		mockOIDCClient.EXPECT().
 			GetTokenByAuthCode(gomock.Any(), gomock.Any(), gomock.Any()).
 			Do(func(_ context.Context, _ oidcclient.GetTokenByAuthCodeInput, readyChan chan<- string) {

pkg/usecases/authentication/authcode_keyboard.go

@@ -7,6 +7,7 @@ import (
 	"github.com/int128/kubelogin/pkg/adaptors/oidcclient"
 	"github.com/int128/kubelogin/pkg/adaptors/reader"
 	"github.com/int128/kubelogin/pkg/domain/oidc"
+	"github.com/int128/kubelogin/pkg/domain/pkce"
 	"golang.org/x/xerrors"
 )
 
@@ -20,7 +21,7 @@ type AuthCodeKeyboard struct {
 }
 
 func (u *AuthCodeKeyboard) Do(ctx context.Context, o *AuthCodeKeyboardOption, client oidcclient.Interface) (*Output, error) {
-	u.Logger.V(1).Infof("performing the authorization code flow with keyboard interactive")
+	u.Logger.V(1).Infof("starting the authorization code flow with keyboard interactive")
 	state, err := oidc.NewState()
 	if err != nil {
 		return nil, xerrors.Errorf("could not generate a state: %w", err)
@@ -29,33 +30,34 @@ func (u *AuthCodeKeyboard) Do(ctx context.Context, o *AuthCodeKeyboardOption, cl
 	if err != nil {
 		return nil, xerrors.Errorf("could not generate a nonce: %w", err)
 	}
-	p, err := oidc.NewPKCEParams()
+	p, err := pkce.New(client.SupportedPKCEMethods())
 	if err != nil {
 		return nil, xerrors.Errorf("could not generate PKCE parameters: %w", err)
 	}
 	authCodeURL := client.GetAuthCodeURL(oidcclient.AuthCodeURLInput{
 		State:                  state,
 		Nonce:                  nonce,
-		CodeChallenge:          p.CodeChallenge,
-		CodeChallengeMethod:    p.CodeChallengeMethod,
+		PKCEParams:             p,
 		RedirectURI:            oobRedirectURI,
 		AuthRequestExtraParams: o.AuthRequestExtraParams,
 	})
-	u.Logger.Printf("Open %s", authCodeURL)
+	u.Logger.Printf("Please visit the following URL in your browser: %s", authCodeURL)
 	code, err := u.Reader.ReadString(authCodeKeyboardPrompt)
 	if err != nil {
 		return nil, xerrors.Errorf("could not read an authorization code: %w", err)
 	}
 
+	u.Logger.V(1).Infof("exchanging the code and token")
 	tokenSet, err := client.ExchangeAuthCode(ctx, oidcclient.ExchangeAuthCodeInput{
-		Code:         code,
-		CodeVerifier: p.CodeVerifier,
-		Nonce:        nonce,
-		RedirectURI:  oobRedirectURI,
+		Code:        code,
+		PKCEParams:  p,
+		Nonce:       nonce,
+		RedirectURI: oobRedirectURI,
 	})
 	if err != nil {
 		return nil, xerrors.Errorf("could not exchange the authorization code: %w", err)
 	}
+	u.Logger.V(1).Infof("finished the authorization code flow with keyboard interactive")
 	return &Output{
 		IDToken:       tokenSet.IDToken,
 		IDTokenClaims: tokenSet.IDTokenClaims,

pkg/usecases/authentication/authcode_keyboard_test.go

@@ -33,6 +33,7 @@ func TestAuthCodeKeyboard_Do(t *testing.T) {
 			AuthRequestExtraParams: map[string]string{"ttl": "86400", "reauth": "true"},
 		}
 		mockOIDCClient := mock_oidcclient.NewMockInterface(ctrl)
+		mockOIDCClient.EXPECT().SupportedPKCEMethods()
 		mockOIDCClient.EXPECT().
 			GetAuthCodeURL(nonNil).
 			Do(func(in oidcclient.AuthCodeURLInput) {

pkg/usecases/authentication/authentication.go

@@ -49,6 +49,7 @@ type GrantOptionSet struct {
 type AuthCodeOption struct {
 	SkipOpenBrowser        bool
 	BindAddress            []string
+	RedirectURLHostname    string
 	AuthRequestExtraParams map[string]string
 }
 
@@ -86,7 +87,7 @@ const passwordPrompt = "Password: "
 // If the Password is not set, it asks a password by the prompt.
 //
 type Authentication struct {
-	NewOIDCClient    oidcclient.NewFunc
+	OIDCClient       oidcclient.FactoryInterface
 	Logger           logger.Interface
 	Clock            clock.Interface
 	AuthCode         *AuthCode
@@ -117,14 +118,13 @@ func (u *Authentication) Do(ctx context.Context, in Input) (*Output, error) {
 	}
 
 	u.Logger.V(1).Infof("initializing an OpenID Connect client")
-	client, err := u.NewOIDCClient(ctx, oidcclient.Config{
+	client, err := u.OIDCClient.New(ctx, oidcclient.Config{
 		IssuerURL:     in.IssuerURL,
 		ClientID:      in.ClientID,
 		ClientSecret:  in.ClientSecret,
 		ExtraScopes:   in.ExtraScopes,
 		CertPool:      in.CertPool,
 		SkipTLSVerify: in.SkipTLSVerify,
-		Logger:        u.Logger,
 	})
 	if err != nil {
 		return nil, xerrors.Errorf("oidc error: %w", err)

pkg/usecases/authentication/authentication_test.go

@@ -7,8 +7,6 @@ import (
 
 	"github.com/golang/mock/gomock"
 	"github.com/google/go-cmp/cmp"
-	"github.com/google/go-cmp/cmp/cmpopts"
-	"github.com/int128/kubelogin/pkg/adaptors/logger"
 	"github.com/int128/kubelogin/pkg/adaptors/oidcclient"
 	"github.com/int128/kubelogin/pkg/adaptors/oidcclient/mock_oidcclient"
 	"github.com/int128/kubelogin/pkg/domain/jwt"
@@ -18,8 +16,6 @@ import (
 	"golang.org/x/xerrors"
 )
 
-var cmpIgnoreLogger = cmpopts.IgnoreInterfaces(struct{ logger.Interface }{})
-
 func TestAuthentication_Do(t *testing.T) {
 	timeout := 5 * time.Second
 	expiryTime := time.Date(2020, 1, 2, 3, 4, 5, 0, time.UTC)
@@ -92,16 +88,14 @@ func TestAuthentication_Do(t *testing.T) {
 				IDTokenClaims: dummyClaims,
 			}, nil)
 		u := Authentication{
-			NewOIDCClient: func(_ context.Context, got oidcclient.Config) (oidcclient.Interface, error) {
-				want := oidcclient.Config{
+			OIDCClient: &oidcclientFactory{
+				t:      t,
+				client: mockOIDCClient,
+				want: oidcclient.Config{
 					IssuerURL:    "https://issuer.example.com",
 					ClientID:     "YOUR_CLIENT_ID",
 					ClientSecret: "YOUR_CLIENT_SECRET",
-				}
-				if diff := cmp.Diff(want, got, cmpIgnoreLogger); diff != "" {
-					t.Errorf("mismatch (-want +got):\n%s", diff)
-				}
-				return mockOIDCClient, nil
+				},
 			},
 			Logger: testingLogger.New(t),
 			Clock:  clock.Fake(expiryTime.Add(+time.Hour)),
@@ -139,6 +133,7 @@ func TestAuthentication_Do(t *testing.T) {
 			RefreshToken: "EXPIRED_REFRESH_TOKEN",
 		}
 		mockOIDCClient := mock_oidcclient.NewMockInterface(ctrl)
+		mockOIDCClient.EXPECT().SupportedPKCEMethods()
 		mockOIDCClient.EXPECT().
 			Refresh(ctx, "EXPIRED_REFRESH_TOKEN").
 			Return(nil, xerrors.New("token has expired"))
@@ -153,16 +148,14 @@ func TestAuthentication_Do(t *testing.T) {
 				IDTokenClaims: dummyClaims,
 			}, nil)
 		u := Authentication{
-			NewOIDCClient: func(_ context.Context, got oidcclient.Config) (oidcclient.Interface, error) {
-				want := oidcclient.Config{
+			OIDCClient: &oidcclientFactory{
+				t:      t,
+				client: mockOIDCClient,
+				want: oidcclient.Config{
 					IssuerURL:    "https://issuer.example.com",
 					ClientID:     "YOUR_CLIENT_ID",
 					ClientSecret: "YOUR_CLIENT_SECRET",
-				}
-				if diff := cmp.Diff(want, got, cmpIgnoreLogger); diff != "" {
-					t.Errorf("mismatch (-want +got):\n%s", diff)
-				}
-				return mockOIDCClient, nil
+				},
 			},
 			Logger: testingLogger.New(t),
 			Clock:  clock.Fake(expiryTime.Add(+time.Hour)),
@@ -209,16 +202,14 @@ func TestAuthentication_Do(t *testing.T) {
 				IDTokenClaims: dummyClaims,
 			}, nil)
 		u := Authentication{
-			NewOIDCClient: func(_ context.Context, got oidcclient.Config) (oidcclient.Interface, error) {
-				want := oidcclient.Config{
+			OIDCClient: &oidcclientFactory{
+				t:      t,
+				client: mockOIDCClient,
+				want: oidcclient.Config{
 					IssuerURL:    "https://issuer.example.com",
 					ClientID:     "YOUR_CLIENT_ID",
 					ClientSecret: "YOUR_CLIENT_SECRET",
-				}
-				if diff := cmp.Diff(want, got, cmpIgnoreLogger); diff != "" {
-					t.Errorf("mismatch (-want +got):\n%s", diff)
-				}
-				return mockOIDCClient, nil
+				},
 			},
 			Logger: testingLogger.New(t),
 			ROPC: &ROPC{
@@ -239,3 +230,16 @@ func TestAuthentication_Do(t *testing.T) {
 		}
 	})
 }
+
+type oidcclientFactory struct {
+	t      *testing.T
+	client oidcclient.Interface
+	want   oidcclient.Config
+}
+
+func (f *oidcclientFactory) New(_ context.Context, got oidcclient.Config) (oidcclient.Interface, error) {
+	if diff := cmp.Diff(f.want, got); diff != "" {
+		f.t.Errorf("mismatch (-want +got):\n%s", diff)
+	}
+	return f.client, nil
+}

pkg/usecases/authentication/password.go

@@ -16,7 +16,7 @@ type ROPC struct {
 }
 
 func (u *ROPC) Do(ctx context.Context, in *ROPCOption, client oidcclient.Interface) (*Output, error) {
-	u.Logger.V(1).Infof("performing the resource owner password credentials flow")
+	u.Logger.V(1).Infof("starting the resource owner password credentials flow")
 	if in.Username == "" {
 		var err error
 		in.Username, err = u.Reader.ReadString(usernamePrompt)
@@ -35,6 +35,7 @@ func (u *ROPC) Do(ctx context.Context, in *ROPCOption, client oidcclient.Interfa
 	if err != nil {
 		return nil, xerrors.Errorf("resource owner password credentials flow error: %w", err)
 	}
+	u.Logger.V(1).Infof("finished the resource owner password credentials flow")
 	return &Output{
 		IDToken:       tokenSet.IDToken,
 		IDTokenClaims: tokenSet.IDTokenClaims,

pkg/usecases/setup/stage2.go

@@ -18,19 +18,9 @@ You got a token with the following claims:
 
 ## 3. Bind a cluster role
 
-Apply the following manifest:
+Run the following command:
 
-	kind: ClusterRoleBinding
-	apiVersion: rbac.authorization.k8s.io/v1
-	metadata:
-	  name: oidc-cluster-admin
-	roleRef:
-	  apiGroup: rbac.authorization.k8s.io
-	  kind: ClusterRole
-	  name: cluster-admin
-	subjects:
-	- kind: User
-	  name: {{ .IssuerURL }}#{{ .Subject }}
+	kubectl create clusterrolebinding oidc-cluster-admin --clusterrole=cluster-admin --user='{{ .IssuerURL }}#{{ .Subject }}'
 
 ## 4. Set up the Kubernetes API server
 
@@ -49,7 +39,7 @@ Run the following command:
 	  --exec-arg=oidc-login \
 	  --exec-arg=get-token \
 {{- range .Args }}
-	  --exec-arg={{ . }}
+	  --exec-arg={{ . }} \
 {{- end }}
 
 ## 6. Verify cluster access

snapcraft.yaml

@@ -1,19 +0,0 @@
-name: kubelogin
-version: git
-summary: Log in to the OpenID Connect provider
-description: |
-  This is a kubectl plugin for Kubernetes OpenID Connect (OIDC) authentication.
-confinement: strict
-base: core18
-parts:
-  kubelogin:
-    plugin: nil
-    source: .
-    source-type: git
-    build-snaps: [go]
-    override-build: |
-      make CIRCLE_TAG=$SNAPCRAFT_PROJECT_VERSION
-      cp -av kubelogin $SNAPCRAFT_PART_INSTALL/bin
-apps:
-  kubelogin:
-    command: bin/kubelogin

system_test/Makefile

@@ -0,0 +1,109 @@
+CLUSTER_NAME := kubelogin-system-test
+OUTPUT_DIR := $(CURDIR)/output
+
+PATH := $(PATH):$(OUTPUT_DIR)/bin
+export PATH
+KUBECONFIG := $(OUTPUT_DIR)/kubeconfig.yaml
+export KUBECONFIG
+
+# run the login script instead of opening chrome
+BROWSER := $(OUTPUT_DIR)/bin/chromelogin
+export BROWSER
+
+.PHONY: test
+test: build
+	# see the setup instruction
+	kubectl oidc-login setup \
+		--oidc-issuer-url=https://dex-server:10443/dex \
+		--oidc-client-id=YOUR_CLIENT_ID \
+		--oidc-client-secret=YOUR_CLIENT_SECRET \
+		--oidc-extra-scope=email \
+		--certificate-authority=$(OUTPUT_DIR)/ca.crt
+	# set up the kubeconfig
+	kubectl config set-credentials oidc \
+		--exec-api-version=client.authentication.k8s.io/v1beta1 \
+		--exec-command=kubectl \
+		--exec-arg=oidc-login \
+		--exec-arg=get-token \
+		--exec-arg=--oidc-issuer-url=https://dex-server:10443/dex \
+		--exec-arg=--oidc-client-id=YOUR_CLIENT_ID \
+		--exec-arg=--oidc-client-secret=YOUR_CLIENT_SECRET \
+		--exec-arg=--oidc-extra-scope=email \
+		--exec-arg=--certificate-authority=$(OUTPUT_DIR)/ca.crt
+	# make sure we can access the cluster
+	kubectl --user=oidc cluster-info
+	# switch the current context
+	kubectl config set-context --current --user=oidc
+	# make sure we can access the cluster
+	kubectl cluster-info
+
+.PHONY: setup
+setup: build dex cluster setup-chrome
+
+.PHONY: setup-chrome
+setup-chrome: $(OUTPUT_DIR)/ca.crt
+	# add the dex server certificate to the trust store
+	mkdir -p ~/.pki/nssdb
+	cd ~/.pki/nssdb && certutil -A -d sql:. -n dex -i $(OUTPUT_DIR)/ca.crt -t "TC,,"
+
+# build binaries
+.PHONY: build
+build: $(OUTPUT_DIR)/bin/kubectl-oidc_login $(OUTPUT_DIR)/bin/chromelogin
+$(OUTPUT_DIR)/bin/kubectl-oidc_login:
+	go build -o $@ ..
+$(OUTPUT_DIR)/bin/chromelogin: chromelogin/main.go
+	go build -o $@ ./chromelogin
+
+# create a Dex server
+.PHONY: dex
+dex: $(OUTPUT_DIR)/server.crt $(OUTPUT_DIR)/server.key
+	docker create --name dex-server -p 10443:10443 --network kind quay.io/dexidp/dex:v2.21.0 serve /dex.yaml
+	docker cp $(OUTPUT_DIR)/server.crt dex-server:/
+	docker cp $(OUTPUT_DIR)/server.key dex-server:/
+	docker cp dex.yaml dex-server:/
+	docker start dex-server
+	docker logs dex-server
+
+$(OUTPUT_DIR)/ca.key:
+	mkdir -p $(OUTPUT_DIR)
+	openssl genrsa -out $@ 2048
+$(OUTPUT_DIR)/ca.csr: $(OUTPUT_DIR)/ca.key
+	openssl req -new -key $(OUTPUT_DIR)/ca.key -out $@ -subj "/CN=dex-ca" -config openssl.cnf
+$(OUTPUT_DIR)/ca.crt: $(OUTPUT_DIR)/ca.key $(OUTPUT_DIR)/ca.csr
+	openssl x509 -req -in $(OUTPUT_DIR)/ca.csr -signkey $(OUTPUT_DIR)/ca.key -out $@ -days 10
+$(OUTPUT_DIR)/server.key:
+	mkdir -p $(OUTPUT_DIR)
+	openssl genrsa -out $@ 2048
+$(OUTPUT_DIR)/server.csr: openssl.cnf $(OUTPUT_DIR)/server.key
+	openssl req -new -key $(OUTPUT_DIR)/server.key -out $@ -subj "/CN=dex-server" -config openssl.cnf
+$(OUTPUT_DIR)/server.crt: openssl.cnf $(OUTPUT_DIR)/server.csr $(OUTPUT_DIR)/ca.crt $(OUTPUT_DIR)/ca.key
+	openssl x509 -req -in $(OUTPUT_DIR)/server.csr -CA $(OUTPUT_DIR)/ca.crt -CAkey $(OUTPUT_DIR)/ca.key -CAcreateserial -out $@ -sha256 -days 10 -extensions v3_req -extfile openssl.cnf
+
+# create a Kubernetes cluster
+.PHONY: cluster
+cluster: dex create-cluster
+	# add the Dex container IP to /etc/hosts of kube-apiserver
+	docker inspect -f '{{.NetworkSettings.IPAddress}}' dex-server | sed -e 's,$$, dex-server,' | \
+		kubectl -n kube-system exec -i kube-apiserver-$(CLUSTER_NAME)-control-plane -- tee -a /etc/hosts
+	# wait for kube-apiserver oidc initialization
+	# (oidc authenticator will retry oidc discovery every 10s)
+	sleep 10
+
+.PHONY: create-cluster
+create-cluster: $(OUTPUT_DIR)/ca.crt
+	cp $(OUTPUT_DIR)/ca.crt /tmp/kubelogin-system-test-dex-ca.crt
+	kind create cluster --name $(CLUSTER_NAME) --config cluster.yaml
+	kubectl create clusterrole cluster-readonly --verb=get,watch,list --resource='*.*'
+	kubectl create clusterrolebinding cluster-readonly --clusterrole=cluster-readonly --user=admin@example.com
+
+# clean up the resources
+.PHONY: clean
+clean:
+	-rm -r $(OUTPUT_DIR)
+.PHONY: delete-cluster
+delete-cluster:
+	kind delete cluster --name $(CLUSTER_NAME)
+.PHONY: delete-dex
+delete-dex:
+	docker stop dex-server
+	docker rm dex-server

system_test/README.md

@@ -0,0 +1,112 @@
+# kubelogin/system_test
+
+This is an automated test for verifying behavior of the plugin with a real Kubernetes cluster and OIDC provider.
+
+
+## Purpose
+
+This test checks the following points:
+
+1. User can set up Kubernetes OIDC authentication using [setup guide](../docs/setup.md).
+1. User can log in to an OIDC provider on a browser.
+1. User can access the cluster using a token returned from the plugin.
+
+It depends on the following components:
+
+- Kubernetes cluster (Kind)
+- OIDC provider (Dex)
+- Browser (Chrome)
+- kubectl command
+
+
+## How it works
+
+Let's take a look at the diagram.
+
+![diagram](../docs/system-test-diagram.svg)
+
+It prepares the following resources:
+
+1. Generate a pair of CA certificate and TLS server certificate for Dex.
+1. Run Dex on a container.
+1. Create a Kubernetes cluster using Kind.
+1. Mutate `/etc/hosts` of the CI machine to access Dex.
+1. Mutate `/etc/hosts` of the kube-apiserver pod to access Dex.
+
+It performs the test by the following steps:
+
+1. Run kubectl.
+1. kubectl automatically runs kubelogin.
+1. kubelogin automatically runs [chromelogin](chromelogin).
+1. chromelogin opens the browser, navigates to `http://localhost:8000` and enter the username and password.
+1. kubelogin gets an authorization code from the browser.
+1. kubelogin gets a token.
+1. kubectl accesses an API with the token.
+1. kube-apiserver verifies the token by Dex.
+1. Check if kubectl exited with code 0.
+
+
+## Run locally
+
+You need to set up the following components:
+
+- Docker
+- Kind
+- Chrome or Chromium
+
+You need to add the following line to `/etc/hosts` so that the browser can access the Dex.
+
+```
+127.0.0.1 dex-server
+```
+
+Run the test.
+
+```shell script
+# run the test
+make
+
+# clean up
+make delete-cluster
+make delete-dex
+```
+
+
+## Technical consideration
+
+### Network and DNS
+
+Consider the following issues:
+
+- kube-apiserver runs on the host network of the kind container.
+- kube-apiserver cannot resolve a service name by kube-dns.
+- kube-apiserver cannot access a cluster IP.
+- kube-apiserver can access another container via the Docker network.
+- Chrome requires exactly match of domain name between Dex URL and a server certificate.
+
+Consequently,
+
+- kube-apiserver accesses Dex by resolving `/etc/hosts` and via the Docker network.
+- kubelogin and Chrome accesses Dex by resolving `/etc/hosts` and via the Docker network.
+
+### TLS server certificate
+
+Consider the following issues:
+
+- kube-apiserver requires `--oidc-issuer` is HTTPS URL.
+- kube-apiserver requires a CA certificate at startup, if `--oidc-ca-file` is given.
+- kube-apiserver mounts `/usr/local/share/ca-certificates` from the kind container.
+- It is possible to mount a file from the CI machine.
+- It is not possible to issue a certificate using Let's Encrypt in runtime.
+- Chrome requires a valid certificate in `~/.pki/nssdb`.
+
+As a result,
+
+- kube-apiserver uses the CA certificate of `/usr/local/share/ca-certificates/dex-ca.crt`. See the `extraMounts` section of [`cluster.yaml`](cluster.yaml).
+- kubelogin uses the CA certificate in `output/ca.crt`.
+- Chrome uses the CA certificate in `~/.pki/nssdb`.
+
+### Test environment
+
+- Set the issuer URL to kube-apiserver. See [`cluster.yaml`](cluster.yaml).
+- Set `BROWSER` environment variable to run [`chromelogin`](chromelogin) by `xdg-open`.

system_test/cluster.yaml

@@ -0,0 +1,20 @@
+kind: Cluster
+apiVersion: kind.x-k8s.io/v1alpha4
+# https://github.com/dexidp/dex/blob/master/Documentation/kubernetes.md
+kubeadmConfigPatches:
+  - |
+    apiVersion: kubeadm.k8s.io/v1beta2
+    kind: ClusterConfiguration
+    metadata:
+      name: config
+    apiServer:
+      extraArgs:
+        oidc-issuer-url: https://dex-server:10443/dex
+        oidc-client-id: YOUR_CLIENT_ID
+        oidc-username-claim: email
+        oidc-ca-file: /usr/local/share/ca-certificates/dex-ca.crt
+nodes:
+  - role: control-plane
+    extraMounts:
+      - hostPath: /tmp/kubelogin-system-test-dex-ca.crt
+        containerPath: /usr/local/share/ca-certificates/dex-ca.crt