Click (Meta) Command to run a list of commands

I need to be able to trigger multiple click commands from one command on the CLI

Let’s say I have a click group

@click.group()
def cli():
    pass

@cli.command()
def a():
    print("A")

@cli.command()
def b():
    print ("B")

What functionality should I add to run an ordered list of the commands like the following?

$ python -m my_cli_module a,b
A
B

The goal is that there are shared variables which get initialized for each of my commands. The init is expensive and I’d like to run the init exactly once.

Answer

To chain your commands, you have to pass chain=True to your group. For more information see this part of the documentation.

You could use the @click.pass_context decorator on the group to store the result of your initialisation:

@click.group(chain=True)
@click.pass_context
def cli(ctx):
    # Your init here resulting in an object
    ctx.obj = the_result_of_your_init

and then you need to use the @click.pass_obj decorator on the commands to use the result object:

@cli.command()
@click.pass_obj
def a(my_obj): # The first param of the command is the passed object
    print("A")

The pattern above is useful to share resources. I used it to share my sqlite db connection as an example.

For more information see the following documents:

pass_context documentation

pass_obj documentation

Another way to achieve this is to use multi command pipelines.