allow alias generator to access FieldInfo, and particularly its aliases

MarcBresson commented 2 months ago

Initial Checks

[X] I have searched Google & GitHub for similar requests and couldn't find anything
[X] I have read and followed the docs and still think this feature is missing

Description

allow alias generator to access FieldInfo, and particularly its aliases.

It would allow users to generate aliases based on already present aliases

def upper_aliases_generator(field_name: str, field_info: FieldInfo) -> list[str]:
    if isinstance(field_info.alias, AliasChoices):
        aliases = list(field_info.alias)
    elif instance(field_info.alias, str):
        aliases = [field_info.alias]

    generated_aliases = [field_name.upper()]
    for alias in aliases:
        generated_aliases.append(alias.upper())

    return generated_aliases

class A(BaseModel):
    model_config = ConfigDict(alias_generator=upper_aliases_generator)

    SmallTest: str = Field(alias=AliasChoices("small_test", "small_test_"), alias_priority=1)

A(SMALLTEST="hey")
#> A(SmallTest="hey")

A(SMALL_TEST="hey")
#> A(SmallTest="hey")

A(SMALL_TEST_="hey")
#> A(SmallTest="hey")

Affected Components

[ ] Compatibility between releases
[X] Data validation/parsing
[ ] Data serialization - .model_dump() and .model_dump_json()
[ ] JSON Schema
[ ] Dataclasses
[ ] Model Config
[ ] Field Types - adding or changing a particular data type
[ ] Function validation decorator
[ ] Generic Models
[ ] Other Model behaviour - model_construct(), pickling, private attributes, ORM mode
[ ] Plugins and integration with other tools - mypy, FastAPI, python-devtools, Hypothesis, VS Code, PyCharm, etc.

sydney-runkle commented 2 months ago

Interesting feature request! I'm not opposed. Wdyt @Viicos?

sydney-runkle commented 2 months ago

I can open a PR with support for this in v2.10, potentially.

Viicos commented 2 months ago

The thing is we don't support using AliasChoices/AliasPath for alias.

I don't recall exactly how alias_generator plays with validation_alias/serialization_alias, might be good looking into this.

Perhaps https://github.com/pydantic/pydantic/issues/8379 could be tackled first (I don't know if it relates with this issue or not).

sydney-runkle commented 2 months ago

Yeah, #8379 is definitely higher prio.

pydantic / pydantic