Write Your Own Kubernetes Sub-Command [Part 9]
source link: https://hackernoon.com/write-your-own-kubernetes-sub-command-part-9-46y32u8
Go to the source link to view the article. You can view the picture content, updated content and better typesetting reading experience. If the link is broken, please click the button below to view the snapshot at that time.
Write Your Own Kubernetes Sub-Command [Part 9]
@jameshuntJames Hunt
R&D at Stark & Wayne, finding software solutions to customer problems and changing them into executable best practices.
Eventually, you'll write a super handy script for interacting with Kubernetes – I have no doubt. Wouldn't it be stellar if you could pretend that your script was officially part of the
kubectl
You can!
kubectlgit$ kubectl fu
Error: unknown command "fu" for "kubectl"
Did you mean this?
run
cp
Run 'kubectl --help' for usage.Before it spits out the usage screen, however,
kubectl$PATHkubectl-$COMMAND$ echo $PATH
/Users/jhunt/bin:/usr/bin:/bin:/usr/sbin:/sbin
$ cat ~/bin/kubectl-fu
#!/bin/sh
echo "the kubernetes is strong with this one..."
$ kubectl fu
the kubernetes is strong with this one...It doesn't matter what you write your program in; hack up some Bash, compile some Go or Rust, even write it in Perl or Python! As long as it is in
$PATHHere's a more potent and useful example, which uses a bit of Go magic to handle the base64 encoding that Kubernetes puts on all of its Secrets.
If you store secrets in Kubernetes, they get encrypted at rest, and are returned by the API encoded using the Base 64 scheme. While the particulars of the algorithm are interesting, using the encoded data is a bit of a pain.
$ kubectl get secret creds -o jsonpath='{.data.password}'
aXQncyBhIHNlY3JldCB0byBldmVyeWJvZHkuLuckily, we can use Go templates to format data we get from the API. What's more, the template language has the ability to decode base64-encoded data, natively! Here's a first attempt at extracting the data:
$ kubectl get secret creds -o template='{{.data.password | base64decode }}'
it's a secret to everybody.That's mighty useful. If we package it up as the new
kubectl decode$ cat ~/bin/kubectl-decode
#!/bin/sh
exec kubectl get secret -o template='{{.data.password | base64decode }}' "$@"
$ chmod 0755 ~/bin/kubectl-decode
$ kubectl decode creds
it's a secret to everybody.Also seen here.
R&D at Stark & Wayne, finding software solutions to customer problems and changing them into executable best practices.
Create your free account to unlock your custom reading experience.
Recommend
About Joyk
Aggregate valuable and interesting links.
Joyk means Joy of geeK