test: setup pytests

.env.example

@@ -47,7 +47,7 @@ APP_PORT=8000
 # Postgres database configuration
 POSTGRES_USER=postgres
 POSTGRES_PASSWORD=postgres
-POSTGRES_DB_NAME=codepath_project_postgres_local
+POSTGRES_DB_NAME=postgres
 POSTGRES_DB_HOST=localhost
 POSTGRES_DB_PORT=5432
-SQLALCHEMY_DATABASE_URL=postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@${POSTGRES_DB_HOST}:${POSTGRES_DB_PORT}/${POSTGRES_DB_NAME}
+SQLALCHEMY_DATABASE_URL=postgresql+asyncpg://${POSTGRES_USER}:${POSTGRES_PASSWORD}@${POSTGRES_DB_HOST}:${POSTGRES_DB_PORT}/${POSTGRES_DB_NAME}

config/index.py

@@ -26,9 +26,11 @@ class Config:
     POSTGRES_USER = os.getenv("POSTGRES_USER")
     POSTGRES_PASSWORD = os.getenv("POSTGRES_PASSWORD")
     POSTGRES_DB_NAME = os.getenv("POSTGRES_DB_NAME")
+    POSTGRES_TEST_DB_NAME = os.getenv("POSTGRES_TEST_DB_NAME")
     POSTGRES_DB_HOST = os.getenv("POSTGRES_DB_HOST")
     POSTGRES_DB_PORT = os.getenv("POSTGRES_DB_PORT")
     SQLALCHEMY_DATABASE_URL = f"postgresql+asyncpg://{POSTGRES_USER}:{POSTGRES_PASSWORD}@{POSTGRES_DB_HOST}:{POSTGRES_DB_PORT}/{POSTGRES_DB_NAME}"
+    SQLALCHEMY_TEST_DATABASE_URL = f"postgresql+asyncpg://{POSTGRES_USER}:{POSTGRES_PASSWORD}@{POSTGRES_DB_HOST}:{POSTGRES_DB_PORT}/{POSTGRES_TEST_DB_NAME}"
 
 
 config = Config

tests/conftest.py

@@ -0,0 +1,86 @@
+# Credits: https://github.com/ThomasAitken/demo-fastapi-async-sqlalchemy/blob/main/backend/app/conftest.py
+
+import asyncio
+from contextlib import ExitStack
+
+import pytest
+from alembic.config import Config
+from alembic.migration import MigrationContext
+from alembic.operations import Operations
+from alembic.script import ScriptDirectory
+from config.index import config as settings
+from app.engine.postgresdb import Base, get_db_session, postgresdb as sessionmanager
+from main import app as actual_app
+from asyncpg import Connection
+from fastapi.testclient import TestClient
+
+
+@pytest.fixture(autouse=True)
+def app():
+    with ExitStack():
+        yield actual_app
+
+
+@pytest.fixture
+def client(app):
+    with TestClient(app) as c:
+        yield c
+
+
+@pytest.fixture(scope="session")
+def event_loop(request):
+    loop = asyncio.get_event_loop_policy().new_event_loop()
+    yield loop
+    loop.close()
+
+
+def run_migrations(connection: Connection):
+    config = Config("alembic.ini")
+    config.set_main_option("script_location", "app/migration")
+    config.set_main_option("sqlalchemy.url", settings.SQLALCHEMY_TEST_DATABASE_URL)
+    script = ScriptDirectory.from_config(config)
+
+    def upgrade(rev, context):
+        return script._upgrade_revs("head", rev)
+
+    context = MigrationContext.configure(connection, opts={"target_metadata": Base.metadata, "fn": upgrade})
+
+    with context.begin_transaction():
+        with Operations.context(context):
+            context.run_migrations()
+
+
+@pytest.fixture(scope="session", autouse=True)
+async def setup_database():
+    # Run alembic migrations on test DB
+    async with sessionmanager.connect() as connection:
+        await connection.run_sync(run_migrations)
+
+    yield
+
+    # Teardown
+    await sessionmanager.close()
+
+
+# Each test function is a clean slate
+@pytest.fixture(scope="function", autouse=True)
+async def transactional_session():
+    async with sessionmanager.session() as session:
+        try:
+            await session.begin()
+            yield session
+        finally:
+            await session.rollback()  # Rolls back the outer transaction
+
+
+@pytest.fixture(scope="function")
+async def db_session(transactional_session):
+    yield transactional_session
+
+
+@pytest.fixture(scope="function", autouse=True)
+async def session_override(app, db_session):
+    async def get_db_session_override():
+        yield db_session[0]
+
+    app.dependency_overrides[get_db_session] = get_db_session_override

tests/pytest.ini

@@ -0,0 +1,2 @@
+[pytest]
+asyncio_mode = auto