feat: typer integration

[Slyces]

Integration With Typer

Following #329 requesting whether we could contribute an integration with Typer, here is an initial contribution.

My implementation is taking the click integration as a basis, with two main differences:

• With Typer, we can take in a typer.Typer app directly to access commands and subcommands
• Container injection is done through a callback which should run before every command
• setup_dishka, when using auto_inject=True should be called after the commands have been added to the app

Don't hesitate to provide feedback or ask for modifications.

[Tishka17]

we have moved from tox to nox, please update test run config

[Slyces]

I have addressed the comments and ensured that nox runs successfully locally!

[Lancetnik]

I think, we should pass typer.Context to dishka context as well to provide users with an ability use CLI options and flags in factories.

Just smth like we do for another integrations - https://github.com/reagento/dishka/blob/develop/src/dishka/integrations/fastapi.py#L64

[Slyces]

I think, we should pass typer.Context to dishka context as well to provide users with an ability use CLI options and flags in factories.

Just smth like we do for another integrations - https://github.com/reagento/dishka/blob/develop/src/dishka/integrations/fastapi.py#L64

I'm not 100% sure on what we could achieve that way, would you have an example?

Would it be accessing the flags of a callback or a higher level command?

[Lancetnik]

I think, we should pass typer.Context to dishka context as well to provide users with an ability use CLI options and flags in factories.
Just smth like we do for another integrations - https://github.com/reagento/dishka/blob/develop/src/dishka/integrations/fastapi.py#L64

I'm not 100% sure on what we could achieve that way, would you have an example?

Would it be accessing the flags of a callback or a higher level command?

You should wrap the original handler by your custom decorator with context like this:

from functools import wraps
from typer import Typer, Context

app = Typer()

def inject(func):
    def wrapper(ctx: Context):
        # we should pass this `ctx` object to dishka context
        print(ctx.args)
        return func()
    return wrapper

@app.command()
@inject
def main():
    pass

if __name__ == "__main__":
    app()

But, you should patch wrapper method signature to be a copy of original command with added Context option. You can take a look at signature patching in dishka sources

[Tishka17]

You can refer to fastapi integration to see how we process arguments when decorating

[Tishka17]

I do not think we should do it. I treat typer as well as click as framework which actually just runs app as a whole: inside click/typer handlers there can be other frameworks started (like fastapi, etc.)

So, from my point of view, expected behavior for typer handler is to have Scope.APP, not REQUEST. Let't keep the logic we have for click.

I see the problem now: you cannot pass Context because APP-scoped container is already created. My fault, let's rollback and ignore this requirement.

[Slyces]

Would you go back to typer.Context not being available to providers?

[Tishka17]

Correct. We cannot pass it here, so let it be user's problem.