Extensions are folders that contain clk configurations and commands. You can create and share those with your colleagues.
For instance, let’s suppose you need to bootstrap a development environment to work with k8s, you would need to create commands to:
- install the needed binaries dependencies,
- run the cluster,
- start some controllers of your choice,
- run the development environment that would update the cluster automatically.
creating our own extension
The real life extension can be found in here. In this document, we will mock its behavior. There should be something like.
@k8s.command()
def install_dependencies():
"""Install the required binary dependencies for k8s development."""
print("installing dependencies")
@k8s.command(flowdepends=["k8s.install-dependencies"])
def run_cluster():
"""Start the Kubernetes cluster."""
print("starting k8s cluster")
@k8s.command(flowdepends=["k8s.run-cluster"])
def start_controllers():
"""Start the necessary controllers for the k8s environment."""
print("starting controllers")
@k8s.command(flowdepends=["k8s.start-controllers"])
def run_dev_env():
"""Run the development environment with automatic cluster updates."""
print("running development environment")
To share them, you would first need to create the extension named k8s.
clk extension create k8s
Them, create the k8s command inside the extension.
clk command create --extension k8s python k8s --group --description "Deal with k8s stuff" --body '
@k8s.command()
def install_dependencies():
"""Install the required binary dependencies for k8s development."""
print("installing dependencies")
@k8s.command(flowdepends=["k8s.install-dependencies"])
def run_cluster():
"""Start the Kubernetes cluster."""
print("starting k8s cluster")
@k8s.command(flowdepends=["k8s.run-cluster"])
def start_controllers():
"""Start the necessary controllers for the k8s environment."""
print("starting controllers")
@k8s.command(flowdepends=["k8s.start-controllers"])
def run_dev_env():
"""Run the development environment with automatic cluster updates."""
print("running development environment")
'
Try it with
clk k8s run-dev-env --flow
installing dependencies
starting k8s cluster
starting controllers
running development environment
enable/disable it
Note that once it is there, the extension is automatically enabled.
Now, if you decide that you don’t want to be bothered with that extension anymore, you can disable it.
clk extension disable k8s
clk k8s run-dev-env --flow
Usage: clk [OPTIONS] COMMAND [ARGS]...
error: No such command 'k8s'.
You can enable it again with.
clk extension enable k8s
clk k8s run-dev-env --flow
installing dependencies
starting k8s cluster
starting controllers
running development environment
publish it
In case you lost that extension folder and want to find it again, simply run.
clk extension where-is global/k8s | sed "s|$(pwd)|.|"
./clk-root/extensions/k8s
You can git init that code and push it to some remote repository. Your colleagues then can get it with clk extension install yourextensionurl.
get an extension
Let’s try to install another extension for the sake of learning. Let’s try to install the one available in https://github.com/clk-project/clk_extension_hello . It does nothing useful. It simply says hello in a funny way.
There are three ways to provide the url to the extension:
- use the full url to the git remote,
- if it is hosted in github, and its repository name is something like
clk_extension_NAME, then you can simply pass<GITHUB_OWNER>/<NAME>. This will be automatically changed intohttps://github.com/<GITHUB_OWNER>/clk_extension_<NAME>. - if it is an official extension provided by clk (meaning hosted at https://github.com/orgs/clk-project/repositories with the prefix
clk_extension_), then the name will suffice.
Let’s try the three methods.
clk extension install https://github.com/clk-project/clk_extension_hello > /dev/null 2>&1
clk hello
_____
| hello |
=====
\
\
\
\
/ \\ //\\
|\\___/| / \\// \\\\
/0 0 \\__ / // | \\ \\
/ / \\/_/ // | \\ \\
\@_^_\@'/ \\/_ // | \\ \\
//_^_/ \\/_ // | \\ \\
( //) | \\/// | \\ \\
( / /) _|_ / ) // | \\ _\\
( // /) '/,_ _ _/ ( ; -. | _ _\\.-~ .-~~~^-.
(( / / )) ,-{ _ `-.|.-~-. .~ `.
(( // / )) '/\\ / ~-. _ .-~ .-~^-. \\
(( /// )) `. { } / \\ \\
(( / )) .----~-.\\ \\-' .~ \\ `. \\^-.
///.----..> \\ _ -~ `. ^-` ^-_
///-._ _ _ _ _ _ _}^ - - - - ~ ~-- ,.-~
/.-~
Remove the extension with
clk extension remove hello
clk hello
Usage: clk [OPTIONS] COMMAND [ARGS]...
error: No such command 'hello'.
error:
error: Did you mean one of these?
error: help
error: log
Because it is hosted on github, this should do as well to install it.
clk extension install clk-project/hello > /dev/null 2>&1
clk hello
_____
| hello |
=====
\
\
\
\
/ \\ //\\
|\\___/| / \\// \\\\
/0 0 \\__ / // | \\ \\
/ / \\/_/ // | \\ \\
\@_^_\@'/ \\/_ // | \\ \\
//_^_/ \\/_ // | \\ \\
( //) | \\/// | \\ \\
( / /) _|_ / ) // | \\ _\\
( // /) '/,_ _ _/ ( ; -. | _ _\\.-~ .-~~~^-.
(( / / )) ,-{ _ `-.|.-~-. .~ `.
(( // / )) '/\\ / ~-. _ .-~ .-~^-. \\
(( /// )) `. { } / \\ \\
(( / )) .----~-.\\ \\-' .~ \\ `. \\^-.
///.----..> \\ _ -~ `. ^-` ^-_
///-._ _ _ _ _ _ _}^ - - - - ~ ~-- ,.-~
/.-~
And because this is also a clk provided extension, the name is enough.
clk extension remove hello
clk extension install hello > /dev/null 2>&1
clk hello
_____
| hello |
=====
\
\
\
\
/ \\ //\\
|\\___/| / \\// \\\\
/0 0 \\__ / // | \\ \\
/ / \\/_/ // | \\ \\
\@_^_\@'/ \\/_ // | \\ \\
//_^_/ \\/_ // | \\ \\
( //) | \\/// | \\ \\
( / /) _|_ / ) // | \\ _\\
( // /) '/,_ _ _/ ( ; -. | _ _\\.-~ .-~~~^-.
(( / / )) ,-{ _ `-.|.-~-. .~ `.
(( // / )) '/\\ / ~-. _ .-~ .-~^-. \\
(( /// )) `. { } / \\ \\
(( / )) .----~-.\\ \\-' .~ \\ `. \\^-.
///.----..> \\ _ -~ `. ^-` ^-_
///-._ _ _ _ _ _ _}^ - - - - ~ ~-- ,.-~
/.-~