From 6bc08c0a7e335bdf685aa3149989b791dd845d85 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] 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