🐛 Fix Pydantic alias bug

[STocidlowski]

bug

/This workaround fixes Pydantic serialization/deserialization while not modifying the internal alias logic. I cannot figure out why alias is not being passed through anymore.

For example, I was needing to add schema_extra with these key values in order to read/write data from a Json

• with different field names. I had similar issues to issue Problem with the metadata field (NameError: Field name "metadata" shadows a BaseModel attribute; use a different field name with "alias='metadata'".) #290

https://docs.pydantic.dev/latest/concepts/fields/#field-aliases
#290

Thank you for your consideration.

[jrealpe]

LGTM. I tested it on a SQLModel and it works fine. It keeps the syntax clean by using the same alias field.

[svlandeg]

Hi @STocidlowski, thanks for the contribution! Do you have a minimal reproducible example that shows the bug on main (but has it fixed with this PR)?

[gillespilloudkerlink]

Thanks for this useful fix. It work for my usecase :

Reproductible example :

from sqlmodel import Field, Session, SQLModel, create_engine, select


class Hero(SQLModel, table=True):
    id: int | None = Field(default=None, primary_key=True)
    name: str
    secret_name: str = Field(..., alias="myLittleSecretAlias")  # Using alias for JSON serialization
    age: int | None = None


sqlite_file_name = "database.db"
sqlite_url = f"sqlite:///{sqlite_file_name}"

engine = create_engine(sqlite_url, echo=True)

SQLModel.metadata.create_all(engine)

with Session(engine) as session:

    hero_1 = Hero(name="Deadpond", myLittleSecretAlias="Dive Wilson")
    session.add(hero_1)


    statement = select(Hero).where(Hero.name == "Deadpond")
    hero = session.exec(statement).one_or_none()

    # without the fix the result is :
    #  {'name': 'Deadpond', 'secret_name': 'Dive Wilson', 'id': 1, 'age': None}
    # with the fix it is :
    #  {'name': 'Deadpond', 'myLittleSecretAlias': 'Dive Wilson', 'id': 1, 'age': None}
    print(hero.model_dump(by_alias=True))

[gillespilloudkerlink]

a workaround is the usage of schema_extra={"serialization_alias": "metadata"} instead of the "alias" parameter.

[YuriiMotov]

See also: #1577

[svlandeg]

Thanks @STocidlowski, @jrealpe and @gillespilloudkerlink for your contributions here. I'll go ahead and close this PR in favor of #1577 which is more extensive. But thanks again! 🙏