README.md

How to run tests

Tests are run using Pytest and can be run using:

pytest

How to write API tests

Tests which send requests to an endpoint should use the client fixture defined in tests/conftest.py.

This client is a fastapi.TestClient object which allows you to mock sending requests without an HTTP or socket connection.

Using the TestClient

To implement this client add it as an argument to your test function as shown:

from fastapi.testclient import TestClient

def test_endpoint(client: TestClient):
    pass

This TestClient implements sending requests similarly to the requests module.

from fastapi.testclient import TestClient

def test_endpoint(client: TestClient):
    response = client.get("/endpoint")
    assert response.status_code == 200

from fastapi.testclient import TestClient

def test_endpoint(client: TestClient):
    response = client.post("/endpoint", json={"key": "value"})
    assert response.status_code == 201

View the full documentation for the TestClient here.

Mocking the database

When we run unit tests we do not want to be writing to be writing to a permanent database.

We instead mock the database using an in-memory sqlite database, which is destroyed after each test.

This is handled for us when we use the client pytest fixture, discussed above. This TestClient overwrites the database used by each endpoint.

If you want direct access to this in-memory database for your tests you simply need to include the session fixture defined in tests/conftest.py.

from sqlmodel import Session, select
from app.models.cases import Case
from datetime import datetime as dt

def test_database(session: Session):
    # Create a new case object
    case = Case(id=1, name='test', category='Housing', time=dt.now())
    session.add(case)  # Write it to the database
    
    db_case = session.get(Case, 1)  # Read case with ID: 1 from the database
    assert db_case == case  # Assert they are equal

This session is a sqlmodel.Session object, it inherits from the SQLAlchemy session class. View the SQLModel documentation here.