One to many relationship doesn't return the many

[danielmarkow]

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Example Code

# schema.py
import uuid as uuid_pkg
from typing import List
from sqlmodel import SQLModel, Field, Relationship

class GradeInput(SQLModel):
    grade: int
    snippet: str
    theme_id: uuid_pkg.UUID

class GradeOutput(GradeInput):
    id: uuid_pkg.UUID

class Grade(GradeInput, table=True):
    id: uuid_pkg.UUID | None = Field(default_factory=uuid_pkg.uuid4, primary_key=True)
    theme_id: uuid_pkg.UUID = Field(foreign_key="theme.id")
    theme: "Theme" = Relationship(back_populates="grades")

class ThemeInput(SQLModel):
    theme: str
    differentiation: str

class Theme(ThemeInput, table=True):
    id: uuid_pkg.UUID | None = Field(default_factory=uuid_pkg.uuid4, primary_key=True)
    grades: List["Grade"] = Relationship(back_populates="theme")

class ThemeOutput(ThemeInput):
    id: uuid_pkg.UUID
    grades: List[GradeOutput] = []

# main.py
@app.get("/api/theme")
def get_theme(session: Session = Depends(get_session)) -> list:
    query = select(Theme)
    return session.exec(query).all()

Description

I expected this model to return

{
    "theme": "hello world",
    "differentiation": "Lorem Ipsum...",
    "id": "0dfdb602-3ffc-4420-8346-5c117a87d449",
    "grades": [
    {
        "grade": 2,
        "snippet": "bla bla",
        "theme_id": "0dfdb602-3ffc-4420-8346-5c117a87d449",
        "id": "a443252e-06af-4e25-a0db-ba13f251b449"
    }
]
}

Yet all it returns is

[
    {
        "theme": "hello world",
        "differentiation": "Lorem Ipsum...",
        "id": "0dfdb602-3ffc-4420-8346-5c117a87d449"
    }
]

Any idea why the grades key does not appear?

Operating System

macOS

Operating System Details

Apple M1 MacOS Ventura 13.3.1

SQLModel Version

0.0.8

Python Version

3.11.3

Additional Context

I am using sqlite.

[danielmarkow]

Solved it. The issues was not in the schema definition but in the return type of the route:

@app.get("/api/theme")
def get_theme(session: Session = Depends(get_session)) -> List[ThemeOutput]:
    query = select(Theme)
    return session.exec(query).all()