From 111ff30c38ba586cd074e89ab35466d50fe5914e Mon Sep 17 00:00:00 2001
From: Jerome Petazzoni <jerome.petazzoni@gmail.com>
Date: Sun, 7 Feb 2021 21:41:08 +0100
Subject: [PATCH 1/2] Add k9s section

---
 slides/k8s/k9s.md         | 141 ++++++++++++++++++++++++++++++++++++++
 slides/kube-fullday.yml   |   1 +
 slides/kube-halfday.yml   |   1 +
 slides/kube-selfpaced.yml |   1 +
 slides/kube-twodays.yml   |   1 +
 5 files changed, 145 insertions(+)
 create mode 100644 slides/k8s/k9s.md

diff --git a/slides/k8s/k9s.md b/slides/k8s/k9s.md
new file mode 100644
index 00000000..9c5174e4
--- /dev/null
+++ b/slides/k8s/k9s.md
@@ -0,0 +1,141 @@
+# k9s
+
+- Somewhere in between CLI and GUI (or web UI), we can find the magic land of TUI
+
+  - [Text-based user interfaces](https://en.wikipedia.org/wiki/Text-based_user_interface)
+
+  - often using libraries like [curses](https://en.wikipedia.org/wiki/Curses_%28programming_library%29) and its successors
+
+- Some folks love them, some folks hate them, some are indifferent ...
+
+- But it's nice to have different options!
+
+- Let's see one particular TUI for Kubernetes: [k9s](https://k9scli.io/)
+
+---
+
+## Installing k9s
+
+- If you are using a training cluster or the [shpod](https://github.com/jpetazzo/shpod) image, k9s is pre-installed
+
+- Otherwise, it can be installed easily:
+
+  - with [various package managers](https://k9scli.io/topics/install/)
+
+  - or by fetching a [binary release](https://github.com/derailed/k9s/releases)
+
+- We don't need to set up or configure anything
+
+  (it will use the same configuration as `kubectl` and other well-behaved clients)
+
+- Just run `k9s` to fire it up!
+
+---
+
+## What kind to we want to see?
+
+- Press `:` to change the type of resource to view
+
+- Then type, for instance, `ns` or `namespace` or `nam[TAB]`, then `[ENTER]`
+
+- Use the arrows to move down to e.g. `kube-system`, and press `[ENTER]`
+
+- Or, type `/kub` or `/sys` to filter the output, and press `[ENTER]` twice
+
+  (once to exit the filter, once to enter the namespace)
+
+- We now see the pods in `kube-system`!
+
+---
+
+## Interacting with pods
+
+- `l` to view logs
+
+- `d` to describe
+
+- `s` to get a shell (won't work if `sh` isn't available in the container image)
+
+- `e` to edit
+
+- `shift-f` to define port forwarding
+
+- `ctrl-k` to kill
+
+- `[ESC]` to get out or get back
+
+---
+
+## Quick navigation between namespaces
+
+- On top of the screen, we should see shortcuts like this:
+  ```
+  <0> all
+  <1> kube-system
+  <2> default
+  ```
+
+- Pressing the corresponding number switches to that namespace
+
+  (or shows resources across all namespaces with `0`)
+
+- Locate a namespace with a copy of DockerCoins, and go there!
+
+---
+
+## Interacting with Deployments
+
+- View Deployments (type `:` `deploy` `[ENTER]`)
+
+- Select e.g. `worker`
+
+- Scale it with `s`
+
+- View its aggregated logs with `l`
+
+---
+
+## Exit
+
+- Exit at any time with `Ctrl-C`
+
+- k9s will "remember" where you were
+
+  (and go back there next time you run it)
+
+---
+
+## Pros
+
+- Very convenient to navigate through resources
+
+  (hopping from a deployment, to its pod, to another namespace, etc.)
+
+- Very convenient to quickly view logs of e.g. init containers
+
+- Very convenient to get a (quasi) realtime view of resources
+
+  (if we use `watch kubectl get` a lot, we will probably like k9s)
+
+---
+
+## Cons
+
+- Doesn't promote automation / scripting
+
+  (if you repeat the same things over and over, there is a scripting opportunity)
+
+- Not all features are available
+
+  (e.g. executing arbitrary commands in containers)
+
+---
+
+## Conclusion
+
+Try it out, and see if it makes you more productive!
+
+???
+
+:EN:- The k9s TUI
+:FR:- L'interface texte k9s
diff --git a/slides/kube-fullday.yml b/slides/kube-fullday.yml
index 72c9f631..87ba65d0 100644
--- a/slides/kube-fullday.yml
+++ b/slides/kube-fullday.yml
@@ -58,6 +58,7 @@ content:
   #- k8s/setup-managed.md
   #- k8s/setup-selfhosted.md
   #- k8s/dashboard.md
+  #- k8s/k9s.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md
diff --git a/slides/kube-halfday.yml b/slides/kube-halfday.yml
index 0aaea969..6f4ed3c6 100644
--- a/slides/kube-halfday.yml
+++ b/slides/kube-halfday.yml
@@ -58,6 +58,7 @@ content:
   #- k8s/accessinternal.md
   #- k8s/kubectlproxy.md
 - - k8s/dashboard.md
+  - k8s/k9s.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md
diff --git a/slides/kube-selfpaced.yml b/slides/kube-selfpaced.yml
index 0fe9be4b..90b3d5e3 100644
--- a/slides/kube-selfpaced.yml
+++ b/slides/kube-selfpaced.yml
@@ -59,6 +59,7 @@ content:
   - k8s/setup-managed.md
   - k8s/setup-selfhosted.md
   - k8s/dashboard.md
+  - k8s/k9s.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md
diff --git a/slides/kube-twodays.yml b/slides/kube-twodays.yml
index 638bcc26..e52f7eaf 100644
--- a/slides/kube-twodays.yml
+++ b/slides/kube-twodays.yml
@@ -58,6 +58,7 @@ content:
   #- k8s/setup-managed.md
   #- k8s/setup-selfhosted.md
   - k8s/dashboard.md
+  - k8s/k9s.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md

From 955149e0190e965109854b41c75106f33ce81a20 Mon Sep 17 00:00:00 2001
From: Jerome Petazzoni <jerome.petazzoni@gmail.com>
Date: Sun, 7 Feb 2021 21:44:38 +0100
Subject: [PATCH 2/2] Add Tilt section

---
 dockercoins/Tiltfile      |  49 +++++++
 slides/k8s/tilt.md        | 302 ++++++++++++++++++++++++++++++++++++++
 slides/kube-fullday.yml   |   1 +
 slides/kube-halfday.yml   |   3 +-
 slides/kube-selfpaced.yml |   1 +
 slides/kube-twodays.yml   |   1 +
 6 files changed, 356 insertions(+), 1 deletion(-)
 create mode 100644 dockercoins/Tiltfile
 create mode 100644 slides/k8s/tilt.md

diff --git a/dockercoins/Tiltfile b/dockercoins/Tiltfile
new file mode 100644
index 00000000..d06b8120
--- /dev/null
+++ b/dockercoins/Tiltfile
@@ -0,0 +1,49 @@
+k8s_yaml(blob('''
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  labels:
+    app: registry
+  name: registry
+spec:
+  selector:
+    matchLabels:
+      app: registry
+  template:
+    metadata:
+      labels:
+        app: registry
+    spec:
+      containers:
+      - image: registry
+        name: registry
+---
+apiVersion: v1
+kind: Service
+metadata:
+  labels:
+    app: registry
+  name: registry
+spec:
+  ports:
+  - port: 5000
+    protocol: TCP
+    targetPort: 5000
+    nodePort: 30555
+  selector:
+    app: registry
+  type: NodePort
+'''))
+default_registry('localhost:30555')
+docker_build('dockercoins/hasher', 'hasher')
+docker_build('dockercoins/rng', 'rng')
+docker_build('dockercoins/webui', 'webui')
+docker_build('dockercoins/worker', 'worker')
+k8s_yaml('../k8s/dockercoins.yaml')
+
+# Uncomment the following line to let tilt run with the default kubeadm cluster-admin context.
+#allow_k8s_contexts('kubernetes-admin@kubernetes')
+
+# While we're here: if you're controlling a remote cluster, uncomment that line.
+# It will create a port forward so that you can access the remote registry.
+#k8s_resource(workload='registry', port_forwards='30555:5000')
diff --git a/slides/k8s/tilt.md b/slides/k8s/tilt.md
new file mode 100644
index 00000000..678f005a
--- /dev/null
+++ b/slides/k8s/tilt.md
@@ -0,0 +1,302 @@
+# Tilt
+
+- What does a development workflow look like?
+
+  - make changes
+
+  - test / see these changes
+
+  - repeat!
+
+- What does it look like, with containers?
+
+  🤔
+
+---
+
+## Basic Docker workflow
+
+- Preparation
+
+  - write Dockerfiles
+
+- Iteration
+
+  - edit code
+  - `docker build`
+  - `docker run`
+  - test
+  - `docker stop`
+
+Straightforward when we have a single container.
+
+---
+
+## Docker workflow with volumes
+
+- Preparation
+
+  - write Dockerfiles
+  - `docker build` + `docker run`
+
+- Iteration
+
+  - edit code
+  - test
+
+Note: only works with interpreted languages.
+<br/>
+(Compiled languages require extra work.)
+
+---
+
+## Docker workflow with Compose
+
+- Preparation
+
+  - write Dockerfiles + Compose file
+  - `docker-compose up`
+
+- Iteration
+
+  - edit code
+  - test
+  - `docker-compose up` (as needed)
+
+Simplifies complex scenarios (multiple containers).
+<br/>
+Facilitates updating images.
+
+---
+
+## Basic Kubernetes workflow
+
+- Preparation
+
+  - write Dockerfiles
+  - write Kubernetes YAML
+  - set up container registry
+
+- Iteration
+
+  - edit code
+  - build images
+  - push images
+  - update Kubernetes resources
+
+Seems simple enough, right?
+
+---
+
+## Basic Kubernetes workflow
+
+- Preparation
+
+  - write Dockerfiles
+  - write Kubernetes YAML
+  - **set up container registry**
+
+- Iteration
+
+  - edit code
+  - build images
+  - **push images**
+  - update Kubernetes resources
+
+Ah, right ...
+
+---
+
+## We need a registry
+
+- Remember "build, ship, and run"
+
+- Registries are involved in the "ship" phase
+
+- With Docker, we were building and running on the same node
+
+- We didn't need a registry!
+
+- With Kubernetes, though ...
+
+---
+
+## Special case of single node clusters
+
+- If our Kubernetes has only one node ...
+
+- ... We can build directly on that node ...
+
+- ... We don't need to push images ...
+
+- ... We don't need to run a registry!
+
+- Examples: Docker Desktop, Minikube ...
+
+---
+
+## When we have more than one node
+
+- Which registry should we use?
+
+  (Docker Hub, Quay, cloud-based, self-hosted ...)
+
+- Should we use a single registry, or one per cluster or environment?
+
+- Which tags and credentials should we use?
+
+  (in particular when using a shared registry!)
+
+- How do we provision that registry and its users?
+
+- How do we adjust our Kubernetes YAML manifests?
+
+  (e.g. to inject image names and tags)
+
+---
+
+## More questions
+
+- The whole cycle (build+push+update) is expensive
+
+- If we have many services, how do we update only the ones we need?
+
+- Can we take shortcuts?
+
+  (e.g. synchronized files without going through a whole build+push+update cycle)
+
+---
+
+## Tilt
+
+- Tilt is a tool to address all these questions
+
+- There are other similar tools (e.g. Skaffold)
+
+- We arbitrarily decided to focus on that one
+
+---
+
+## Tilt in practice
+
+- The `dockercoins` directory in our repository has a `Tiltfile`
+
+- Go to that directory and try `tilt up`
+
+- Tilt should refuse to start, but it will explain why
+
+- Edit the `Tiltfile` accordingly and try again
+
+- Open the Tilt web UI
+
+  (if running Tilt on a remote machine, you will need `tilt up --host 0.0.0.0`)
+
+- Watch as the Dockercoins app is built, pushed, started
+
+---
+
+## What's in our Tiltfile?
+
+- Kubernetes manifests for a local registry
+
+- Kubernetes manifests for DockerCoins
+
+- Instructions indicating how to build DockerCoins' images
+
+- A tiny bit of sugar
+
+  (telling Tilt which registry to use)
+
+---
+
+
+## How does it work?
+
+- Tilt keeps track of dependencies between files and resources
+
+  (a bit like a `make` that would run continuously)
+
+- It automatically alters some resources
+
+  (for instance, it updates the images used in our Kubernetes manifests)
+
+- That's it!
+
+(And of course, it provides a great web UI, lots of libraries, etc.)
+
+---
+
+## What happens when we edit a file (1/2)
+
+- Let's change e.g. `worker/worker.py`
+
+- Thanks to this line,
+  ```python
+  docker_build('dockercoins/worker', 'worker')
+  ```
+  ... Tilt watches the `worker` directory and uses it to build `dockercoins/worker`
+
+- Thanks to this line,
+  ```python
+  default_registry('localhost:30555')
+  ```
+  ... Tilt actually renames `dockercoins/worker` to `localhost:30555/dockercoins_worker`
+
+- Tilt will tag the image with something like `tilt-xxxxxxxxxx`
+
+---
+
+## What happens when we edit a file (2/2)
+
+- Thanks to this line,
+  ```python
+  k8s_yaml('../k8s/dockercoins.yaml')
+  ```
+  ... Tilt is aware of our Kubernetes resources
+
+- The `worker` Deployment uses `dockercoins/worker`, so it must be updated
+
+- `dockercoins/worker` becomes `localhost:30555/dockercoins_worker:tilt-xxx`
+
+- The `worker` Deployment gets updated on the Kubernetes cluster
+
+- All these operations (and their log output) are visible in the Tilt UI
+
+---
+
+## Configuration file format
+
+- The Tiltfile is written in [Starlark](https://github.com/bazelbuild/starlark)
+
+  (essentially a subset of Python)
+
+- Tilt monitors the Tiltfile too
+
+  (so it reloads it immediately when we change it)
+
+---
+
+## Tilt "killer features"
+
+- Dependency engine
+
+  (build or run only what's necessary)
+
+- Ability to watch resources
+
+  (execute actions immediately, without explicitly running a command)
+
+- Rich library of function and helpers
+
+  (build container images, manipulate YAML manifests...)
+
+- Convenient UI (web; TUI also available)
+
+  (provides immediate feedback and logs)
+
+- Extensibility!
+
+???
+
+:EN:- Development workflow with Tilt
+:FR:- Développer avec Tilt
diff --git a/slides/kube-fullday.yml b/slides/kube-fullday.yml
index 87ba65d0..17b93bcd 100644
--- a/slides/kube-fullday.yml
+++ b/slides/kube-fullday.yml
@@ -59,6 +59,7 @@ content:
   #- k8s/setup-selfhosted.md
   #- k8s/dashboard.md
   #- k8s/k9s.md
+  #- k8s/tilt.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md
diff --git a/slides/kube-halfday.yml b/slides/kube-halfday.yml
index 6f4ed3c6..42da801c 100644
--- a/slides/kube-halfday.yml
+++ b/slides/kube-halfday.yml
@@ -58,7 +58,8 @@ content:
   #- k8s/accessinternal.md
   #- k8s/kubectlproxy.md
 - - k8s/dashboard.md
-  - k8s/k9s.md
+  #- k8s/k9s.md
+  #- k8s/tilt.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md
diff --git a/slides/kube-selfpaced.yml b/slides/kube-selfpaced.yml
index 90b3d5e3..d725650b 100644
--- a/slides/kube-selfpaced.yml
+++ b/slides/kube-selfpaced.yml
@@ -60,6 +60,7 @@ content:
   - k8s/setup-selfhosted.md
   - k8s/dashboard.md
   - k8s/k9s.md
+  - k8s/tilt.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md
diff --git a/slides/kube-twodays.yml b/slides/kube-twodays.yml
index e52f7eaf..7b8b4de7 100644
--- a/slides/kube-twodays.yml
+++ b/slides/kube-twodays.yml
@@ -59,6 +59,7 @@ content:
   #- k8s/setup-selfhosted.md
   - k8s/dashboard.md
   - k8s/k9s.md
+  #- k8s/tilt.md
   #- k8s/kubectlscale.md
   - k8s/scalingdockercoins.md
   - shared/hastyconclusions.md