Refactoring file structure, not tested yet

app/tests/conftest.py

@@ -0,0 +1,64 @@
+# tests/conftest.py
+
+import pytest
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+from fastapi.testclient import TestClient
+
+from app.main import app
+from app.db.base import Base
+from app.db.session import get_db
+
+
+# Use in-memory SQLite for tests
+TEST_DATABASE_URL = "sqlite+pysqlite:///:memory:"
+
+
+@pytest.fixture(scope="function")
+def db_session():
+    """
+    Creates a new database session for a test.
+    Rolls back everything after test finishes.
+    """
+
+    engine = create_engine(
+        TEST_DATABASE_URL,
+        connect_args={"check_same_thread": False},
+    )
+
+    TestingSessionLocal = sessionmaker(
+        autocommit=False,
+        autoflush=False,
+        bind=engine,
+    )
+
+    # Create tables
+    Base.metadata.create_all(bind=engine)
+
+    db = TestingSessionLocal()
+
+    try:
+        yield db
+    finally:
+        db.close()
+        Base.metadata.drop_all(bind=engine)
+
+
+@pytest.fixture(scope="function")
+def client(db_session):
+    """
+    Overrides get_db dependency to use test database.
+    """
+
+    def override_get_db():
+        try:
+            yield db_session
+        finally:
+            pass
+
+    app.dependency_overrides[get_db] = override_get_db
+
+    with TestClient(app) as c:
+        yield c
+
+    app.dependency_overrides.clear()

app/tests/test_routes.py

@@ -0,0 +1,93 @@
+# tests/test_routes.py
+
+import pytest
+
+
+def test_home(client):
+    response = client.get("/")
+    assert response.status_code == 200
+    assert response.json() == {"message": "URL Shortener API"}
+
+
+def test_health(client):
+    response = client.get("/health")
+    assert response.status_code == 200
+    assert response.json() == {"message": "healthy"}
+
+
+def test_shorten_url(client):
+    response = client.post(
+        "/shorten",
+        json={"url": "https://google.com"},
+    )
+
+    assert response.status_code == 200
+    data = response.json()
+
+    assert "short_url" in data
+    assert data["short_url"].startswith("http://")
+
+
+def test_shorten_invalid_url(client):
+    response = client.post(
+        "/shorten",
+        json={"url": "not-a-valid-url"},
+    )
+
+    assert response.status_code == 422  # Pydantic validation error
+
+
+def test_duplicate_url_returns_same_code(client):
+    r1 = client.post("/shorten", json={"url": "https://example.com"})
+    r2 = client.post("/shorten", json={"url": "https://example.com"})
+
+    assert r1.status_code == 200
+    assert r2.status_code == 200
+
+    assert r1.json()["short_url"] == r2.json()["short_url"]
+
+
+def test_redirect_success(client):
+    shorten = client.post(
+        "/shorten",
+        json={"url": "https://redirect-test.com"},
+    )
+
+    short_url = shorten.json()["short_url"]
+    code = short_url.split("/")[-1]
+
+    response = client.get(f"/{code}", follow_redirects=False)
+
+    assert response.status_code in (302, 307)
+
+
+def test_redirect_404(client):
+    response = client.get("/nonexistent", follow_redirects=False)
+    assert response.status_code == 404
+
+
+def test_stats_success(client):
+    shorten = client.post(
+        "/shorten",
+        json={"url": "https://stats-test.com"},
+    )
+
+    short_url = shorten.json()["short_url"]
+    code = short_url.split("/")[-1]
+
+    # Trigger one click
+    client.get(f"/{code}", follow_redirects=False)
+
+    stats = client.get(f"/stats/{code}")
+
+    assert stats.status_code == 200
+    data = stats.json()
+
+    assert data["original_url"] == "https://stats-test.com"
+    assert data["clicks"] == 1
+    assert "created_at" in data
+
+
+def test_stats_404(client):
+    response = client.get("/stats/doesnotexist")
+    assert response.status_code == 404