More nested meta help page issues

[JuneStepp]

I tried the latest release and found:

• The help page for meta commands don't show the parameters from meta.meta.default.
• meta.meta commands show the parameters from meta.default.
• Non-meta commands except app.default don't show the parameters from meta.meta.default.

[BrianPugh]

Hey @JuneStepp!

Can you explain your use-case a little more? I'm sure there are some meta-meta consistency/bugs, but I'm also a bit hesitant if the fixes make the code significantly more complicated. Is there a way to restructure your app to avoid these structures?

The help page for meta commands don't show the parameters from meta.meta.default.

If i'm interpreting this correctly, this is intended. The relationship is that meta calls it's parent, so the parent doesn't care/concern itself about the meta. By extension, app.meta doesn't do anything with app.meta.meta.

[JuneStepp]

Can you explain your use-case a little more? I'm sure there are some meta-meta consistency/bugs, but I'm also a bit hesitant if the fixes make the code significantly more complicated. Is there a way to restructure your app to avoid these structures?

I explained this trouble in #641 (comment). Every level of a parameter's validation depending on another parameter requires another meta app. In my application that has various games registered to it, I first need to get where the program config directory is in meta.meta.default, then handle program options and selecting a game in meta.default, then finally handle game specific options in app.default. I attach commands that don't depend on the program config to meta.meta and ones that don't depend on a game being selected to meta.

The help page for meta commands don't show the parameters from meta.meta.default.

If i'm interpreting this correctly, this is intended. The relationship is that meta calls it's parent, so the parent doesn't care/concern itself about the meta. By extension, app.meta doesn't do anything with app.meta.meta.

When an app.meta command is called, app.meta.meta.default runs first, so the parameters for it should be in the help page, no?

[BrianPugh]

First things first, I merged in #689 as I ran into an ergonomics issue when typing up the example below. I'll release this soon, but as of right now please use main for playing around with the example below.

Every level of a parameter's validation depending on another parameter requires another meta app.

Have you looked into Groups? I suspect what you are trying to achieve is best accomplished through Group validators. I admit, the documentation there is not very great (and I'd appreciate some help there once we resolve this issue!).

To make the conversation a little more concrete, here's a relatively small minimum-working-example that probably has strong resemblance to what you want:

from dataclasses import dataclass
from pathlib import Path
from typing import Annotated

import cyclopts
from cyclopts import App, Group, Parameter
from cyclopts.validators._group import MutuallyExclusive

app = App(
    name="launcher",
    default_parameter=Parameter(negative=""),
)


def _credential_validator(argument_collection):
    # Filter to only arguments that have values (were provided by the user)
    populated = argument_collection.filter_by(value_set=True)

    # Check if both token and username/password were provided
    if "--token" in populated and ("--username" in populated or "--password" in populated):
        raise ValueError("Cannot supply both TOKEN and USERNAME/PASSWORD.")


_credential_group = Group(name="Credentials", validator=_credential_validator)
cheats = Group(name="Cheats")  # Just for organizing
mods = Group(name="Mods")  # Just for organizing


@Parameter(name="*", show_default=False)
@dataclass(kw_only=True)
class Credentials:
    username: Annotated[str, Parameter(alias="-u", group=_credential_group)] = ""
    """Username to login."""

    password: Annotated[str, Parameter(alias="-p", group=_credential_group)] = ""
    """Password for username."""

    token: Annotated[str, Parameter(alias="-t", group=_credential_group)] = ""
    """Authentication token (instead of username/password)."""


@app.command(group="Games")
def mario(
    *,
    credentials: Credentials | None = None,
    infinite_lives: Annotated[bool, Parameter(group=cheats)] = False,
):
    """An Italian plumber stomping on some Koopas.

    Parameters
    ----------
    infinite_lives: bool
        Give mario an infinite number of lives.
    """
    print(f"{credentials=}")
    print(f"{infinite_lives=}")


_mutually_exclusive_health = Group(validator=MutuallyExclusive())


@app.command(group="Games")
def zelda(
    *,
    credentials: Credentials | None = None,
    infinite_health: Annotated[bool, Parameter(group=(cheats, _mutually_exclusive_health))] = False,
    one_hit_ko: Annotated[bool, Parameter(group=(mods, _mutually_exclusive_health))],
):
    """The adventure awaits our hero of Hyrule.

    Parameters
    ----------
    infinite_health: bool
        Give the player infinite health.
    one_hit_ko: bool
        Taking damage causes instant death.
    """
    print(f"{credentials=}")
    print(f"{infinite_health=}")


@app.meta.default
def meta(
    *tokens: Annotated[str, Parameter(show=False, allow_leading_hyphen=True)],
    config: Path = Path("config.yaml"),
):
    """Customized game launcher.

    Parameters
    ----------
    config: Path
        Path to YAML configuration file.
    """
    app.config = cyclopts.config.Yaml(config, search_parents=True)
    app(tokens)


if __name__ == "__main__":
    app.meta()

Please play around with this and let me know what you think! We can use this example as a concrete way to experiment with logic that we want to implement.

[BrianPugh]

@JuneStepp any update on the topic?

[JuneStepp]

Thanks for the example. I have looked into groups, but I'm only using them for organization. The main reason why group validators don't work for me is because type safety is one of my top priorities. Stuff like if "--user" in argument_collection isn't something I'd use in my code.
I do see that Cyclopts is probably more designed to use typing for convenience than for type safety, but I've done my best to work with it.

[BrianPugh]

I definitely understand the concern. Perhaps the best solution in this situation is to just check it on class-construction ( Credentials in this example)? You can raise CycloptsError("My message here") and it'll get formatted prettily.

[JuneStepp]

Maybe that or in the command like I mentioned in #641 (comment); there's some complicating factors for me, so it would need experimentation. The nested meta apps map best to my needs right now, but I might try manual verification in the future.