marshmallow-code
Question: using SQL Expression Language table definitions
Is this a sane pattern to follow to make use of SQLAlchemyAutoSchema with a non-orm (SQL Expression Language) table definition?
from sqlalchemy import Table, Column, Integer, String, MetaData
from sqlalchemy.orm import mapper
from marshmallow_sqlalchemy import SQLAlchemyAutoSchema
meta = MetaData()
example_table = Table('example', meta,
Column('id', Integer, primary_key=True),
Column('some_field', String),
)
def make_orm(table):
class TableRedef:
pass
mapped = mapper(TableRedef, table)
TableRedef.__mapper__ = mapped
return TableRedef
class ExampleSchema(SQLAlchemyAutoSchema):
class Meta:
model = make_orm(example_table)
If there's a better pattern, please let me know. If this is good, I can make a PR to include it in the examples documentation.
Hey, I'm not a maintainer but only came across your question today, I know it's a bit of a late response!
There isn't any prose section of the docs that addresses this but in the api reference for SQLAlchemyAutoSchema this example exists:
from marshmallow_sqlalchemy import SQLAlchemyAutoSchema, auto_field
from mymodels import User
class UserSchema(SQLAlchemyAutoSchema):
class Meta:
model = User
# OR
# table = User.__table__
created_at = auto_field(dump_only=True)
Notice the commented out part table = User.__table__, which looks to me like you could do this:
class ExampleSchema(SQLAlchemyAutoSchema):
class Meta:
table = example_table
...I haven't tested it but if that didn't work it would be a bug IMO.
Support for generating schemas directly from tables comes from here:
https://github.com/marshmallow-code/marshmallow-sqlalchemy/blob/36c403f9b5dfaee7d04e222cc362ce7a52facb29/src/marshmallow_sqlalchemy/convert.py#L116-L141
Better late than never! Thanks for the reply.
I'll have to take a look and see if that works. I'll follow up when I get the chance. If it does, it would be nice if it were more prominent in the docs.