Command class should provide a way to list currently applied migrations from database

[jameshilliard]

I noticed that Command provides ways to list available migrations via history() and any pending migrations via heads(), however I don't see a method to get a list of migrations that have been applied.

From my understanding a list of applied migrations would not neccesarially identical to history() minus any heads() as one could have applied a migration to a database and then removed the migration file.

I think it would be useful to have an additional method(and maybe associated cli command) which shows the list of applied migrations as queried from the database for debugging purposes.

[waketzheng]

Script to show applied migrations:

from pathlib import Path
from typing import cast

import tomllib
from aerich.models import Aerich
from aerich.utils import get_tortoise_config
from asyncclick import UsageError
from tortoise import Tortoise, run_async


async def main(config="pyproject.toml") -> None:
    config_path = Path(config)
    if not config_path.exists():
        raise UsageError(
            "You need to run `aerich init` first to create the config file."
        )
    content = config_path.read_text("utf-8")
    doc: dict = tomllib.loads(content)
    try:
        tool = cast("dict[str, str]", doc["tool"]["aerich"])
        tortoise_orm = tool["tortoise_orm"]
    except KeyError as e:
        raise UsageError(
            "You need run `aerich init` again when upgrading to aerich 0.6.0+."
        ) from e
    tortoise_config = get_tortoise_config(None, tortoise_orm)  # type:ignore[arg-type]
    print(f"{tortoise_config = }")
    await Tortoise.init(config=tortoise_config)
    objs = await Aerich.all().order_by("-id")
    print("Applied migration files:")
    for i in objs:
        print(i.version)


run_async(main())

[jameshilliard]

Think it makes sense to have a convenience helper in Command and maybe the command line interface that returns this data?

[waketzheng]

For aerich>=0.9.2, code can be as simple as:

import anyio
from aerich import Aerich, TortoiseContext

async def main() -> None:
    async with TortoiseContext():
        objs = await Aerich.all().order_by("-id")
    print("Applied migration files:")
    for i in objs:
        print(i.version)

anyio.run(main)

[waketzheng]

Think it makes sense to have a convenience helper in Command and maybe the command line interface that returns this data?

How about add --verbose option to the history command and show which migrations are applied when running aerich history --verbose?

[jameshilliard]

How about add --verbose option to the history command and show which migrations are applied when running aerich history --verbose?

Hmm, one reason I was thinking it would make sense to have one that shows applied migrations entirely from the database was to debug issues that could be caused by migrations applied from migration files that were at some point deleted later on, so I'm thinking a separate command may make more sense(although a verbose option to history may make sense in addition).