ormar/docs/fastapi.md

The use of ormar with fastapi is quite simple.

Apart from connecting to databases at startup everything else you need to do is substitute pydantic models with ormar models.

Here you can find a very simple sample application code.

!!!warning This example assumes that you already have a database created. If that is not the case please visit database initialization section.

Imports and initialization

First take care of the imports and initialization

--8<-- "../docs_src/fastapi/docs001.py"

Database connection

Next define startup and shutdown events (or use middleware)

• note that this is databases specific setting not the ormar one

--8<-- "../docs_src/fastapi/docs001.py"

!!!info You can read more on connecting to databases in fastapi documentation

Models definition

Define ormar models with appropriate fields.

Those models will be used insted of pydantic ones.

--8<-- "../docs_src/fastapi/docs001.py"

!!!tip You can read more on defining Models in models section.

Fastapi endpoints definition

Define your desired endpoints, note how ormar models are used both as response_model and as a requests parameters.

--8<-- "../docs_src/fastapi/docs001.py"

!!!note Note how ormar Model methods like save() are available straight out of the box after fastapi initializes it for you.

!!!note Note that you can return a Model (or list of Models) directly - fastapi will jsonize it for you

Test the application

Here you have a sample test that will prove that everything works as intended.

Be sure to create the tables first. If you are using pytest you can use a fixture.

@pytest.fixture(autouse=True, scope="module")
def create_test_database():
    engine = sqlalchemy.create_engine(DATABASE_URL)
    metadata.create_all(engine)
    yield
    metadata.drop_all(engine)

# here is a sample test to check the working of the ormar with fastapi

from starlette.testclient import TestClient

def test_all_endpoints():
    # note that TestClient is only sync, don't use asyns here
    client = TestClient(app)
    # note that you need to connect to database manually
    # or use client as contextmanager during tests
    with client as client:
        response = client.post("/categories/", json={"name": "test cat"})
        category = response.json()
        response = client.post(
            "/items/", json={"name": "test", "id": 1, "category": category}
        )
        item = Item(**response.json())
        assert item.pk is not None

        response = client.get("/items/")
        items = [Item(**item) for item in response.json()]
        assert items[0] == item

        item.name = "New name"
        response = client.put(f"/items/{item.pk}", json=item.dict())
        assert response.json() == item.dict()

        response = client.get("/items/")
        items = [Item(**item) for item in response.json()]
        assert items[0].name == "New name"

        response = client.delete(f"/items/{item.pk}", json=item.dict())
        assert response.json().get("deleted_rows", "__UNDEFINED__") != "__UNDEFINED__"
        response = client.get("/items/")
        items = response.json()
        assert len(items) == 0

!!!info You can read more on testing fastapi in fastapi docs.