Add backend tests (#12)

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: Pablo Galindo Salgado <pablogsal@gmail.com>

Author: 3 people

.github/workflows/ci.yml

@@ -41,6 +41,45 @@ jobs:
             exit 1
           fi
 
+  backend-tests:
+    name: Backend tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Check for backend changes
+        id: changes
+        run: |
+          if [ "${{ github.event_name }}" = "push" ]; then
+            CHANGED=$(git diff --name-only ${{ github.event.before }} ${{ github.sha }} 2>/dev/null \
+              || git diff --name-only HEAD~1 HEAD 2>/dev/null \
+              || echo "backend/")
+          else
+            CHANGED=$(git diff --name-only ${{ github.event.pull_request.base.sha }} ${{ github.event.pull_request.head.sha }})
+          fi
+          if echo "$CHANGED" | grep -Eq '^(backend/|\.github/workflows/ci\.yml$)'; then
+            echo "backend=true" >> "$GITHUB_OUTPUT"
+          fi
+      - uses: actions/setup-python@v5
+        if: steps.changes.outputs.backend == 'true'
+        with:
+          python-version: "3.13"
+          cache: pip
+          cache-dependency-path: backend/requirements-dev.txt
+      - name: Install backend dependencies
+        if: steps.changes.outputs.backend == 'true'
+        working-directory: backend
+        run: python -m pip install -r requirements-dev.txt
+      - name: Run Ruff
+        if: steps.changes.outputs.backend == 'true'
+        working-directory: backend
+        run: python -m ruff check .
+      - name: Run tests
+        if: steps.changes.outputs.backend == 'true'
+        working-directory: backend
+        run: python -m pytest tests/ -v --cov=app --cov-report=term-missing
+
   frontend-lint:
     name: Frontend Lint & Typecheck
     runs-on: ubuntu-latest

README.md

@@ -35,16 +35,28 @@ Services start automatically with hot reload:
 ## Development Commands
 
 ### Testing
+
 ```bash
-# Via Docker (recommended)
+# Backend tests
+docker compose -f docker-compose.dev.yml exec backend python -m pytest tests/ -v
+
+# With coverage report
+docker compose -f docker-compose.dev.yml exec backend python -m pytest tests/ --cov=app --cov-report=term-missing
+
+# Frontend checks
 docker compose -f docker-compose.dev.yml exec frontend npm run lint
 docker compose -f docker-compose.dev.yml exec frontend npm run typecheck
-
-# Or locally in the frontend directory
-npm run lint                # ESLint (must pass with zero errors)
-npm run typecheck           # TypeScript type checking
 ```
 
+Backend tests use an in-memory SQLite database, independent of the
+PostgreSQL instance used in development. Each test gets a fresh database
+with empty tables. Fixtures in `backend/tests/conftest.py` provide
+pre-built model instances (commits, binaries, environments, runs,
+benchmark results, auth tokens) that tests can depend on as needed.
+Requests go through `httpx.AsyncClient` with FastAPI's ASGI transport,
+so the full request/response cycle (middleware, dependency injection,
+validation) is exercised without a running server.
+
 Both checks run in CI on pushes to `main` and on pull requests.
 
 ### Populating Mock Data

backend/.coveragerc

@@ -0,0 +1,2 @@
+[run]
+concurrency = greenlet

backend/app/admin_auth.py

@@ -12,8 +12,7 @@
 
 from .database import get_database
 from .models import AdminSession
-from .oauth import github_oauth, GitHubUser
-from .config import get_settings
+from .oauth import GitHubUser
 
 logger = logging.getLogger(__name__)
 
@@ -52,7 +51,7 @@ async def get_admin_session(
         select(AdminSession).where(
             and_(
                 AdminSession.session_token == session_token,
-                AdminSession.is_active == True,
+                AdminSession.is_active.is_(True),
                 AdminSession.expires_at > datetime.now(UTC).replace(tzinfo=None),
             )
         )
@@ -77,7 +76,7 @@ async def cleanup_expired_sessions(db: AsyncSession) -> None:
         select(AdminSession).where(
             and_(
                 AdminSession.expires_at <= datetime.now(UTC).replace(tzinfo=None),
-                AdminSession.is_active == True,
+                AdminSession.is_active.is_(True),
             )
         )
     )

backend/app/auth.py

@@ -1,10 +1,9 @@
 """Authentication utilities for the Memory Tracker API."""
 
-from fastapi import Depends, HTTPException, status, Header
+from fastapi import Depends, Header
 from fastapi.security import HTTPBearer, HTTPAuthorizationCredentials
 from sqlalchemy.ext.asyncio import AsyncSession
 from typing import Annotated
-import logging
 
 from . import models, crud
 from .database import get_database

backend/app/config.py

@@ -3,9 +3,8 @@
 All settings are loaded from environment variables with sensible defaults.
 """
 
-from typing import List, Optional, Union
+from typing import List
 from pydantic_settings import BaseSettings
-from pydantic import field_validator
 from functools import lru_cache
 
 

backend/app/crud.py

@@ -4,7 +4,6 @@
 
 from sqlalchemy import select, desc, and_, func, text
 from sqlalchemy.ext.asyncio import AsyncSession
-from sqlalchemy.orm import selectinload, joinedload, contains_eager
 from typing import List, Optional, Dict, Any
 from datetime import datetime, UTC
 import logging
@@ -257,7 +256,7 @@ async def create_benchmark_result(
         allocation_histogram=result.result_json.allocation_histogram,
         total_allocated_bytes=result.result_json.total_allocated_bytes,
         top_allocating_functions=[
-            func.dict() for func in result.result_json.top_allocating_functions
+            func.model_dump() for func in result.result_json.top_allocating_functions
         ],
         flamegraph_html=result.flamegraph_html,
     )
@@ -411,7 +410,10 @@ async def get_auth_token_by_token(
     """Get an auth token by its token value."""
     result = await db.execute(
         select(models.AuthToken).where(
-            and_(models.AuthToken.token == token, models.AuthToken.is_active == True)
+            and_(
+                models.AuthToken.token == token,
+                models.AuthToken.is_active.is_(True),
+            )
         )
     )
     return result.scalars().first()
@@ -465,7 +467,7 @@ async def get_admin_users(db: AsyncSession) -> List[models.AdminUser]:
     """Get all admin users."""
     result = await db.execute(
         select(models.AdminUser)
-        .where(models.AdminUser.is_active == True)
+        .where(models.AdminUser.is_active.is_(True))
         .order_by(models.AdminUser.added_at)
     )
     return result.scalars().all()
@@ -479,7 +481,7 @@ async def get_admin_user_by_username(
         select(models.AdminUser).where(
             and_(
                 models.AdminUser.github_username == username,
-                models.AdminUser.is_active == True,
+                models.AdminUser.is_active.is_(True),
             )
         )
     )

backend/app/database.py

@@ -1,6 +1,8 @@
+from contextlib import asynccontextmanager
+from typing import AsyncGenerator
+
 import logging
 from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession, async_sessionmaker
-from sqlalchemy.orm import sessionmaker
 from sqlalchemy.exc import OperationalError, StatementError
 from .models import Base
 from .config import get_settings
@@ -85,11 +87,6 @@ async def drop_tables():
     async with engine.begin() as conn:
         await conn.run_sync(Base.metadata.drop_all)
 
-
-from contextlib import asynccontextmanager
-from typing import AsyncGenerator
-
-
 @asynccontextmanager
 async def transaction_scope() -> AsyncGenerator[AsyncSession, None]:
     """

backend/app/factory.py

@@ -3,6 +3,8 @@
 import uuid
 import time
 import logging
+from contextlib import asynccontextmanager
+from typing import AsyncIterator
 from fastapi import FastAPI, Request
 from fastapi.middleware.cors import CORSMiddleware
 
@@ -31,13 +33,44 @@ def create_app(settings=None) -> FastAPI:
     if settings is None:
         settings = get_settings()
 
+    @asynccontextmanager
+    async def lifespan(app: FastAPI) -> AsyncIterator[None]:
+        # Configure logging using the app state before the app starts serving.
+        app.state.logging_manager.configure_logging()
+
+        # Disable uvicorn access logs to avoid duplication
+        uvicorn_logger = logging.getLogger("uvicorn.access")
+        uvicorn_logger.disabled = True
+
+        logger = get_logger("api.startup")
+        logger.info(
+            "Application starting up",
+            extra={
+                "log_level": settings.log_level,
+                "log_format": settings.log_format,
+                "api_version": settings.api_version,
+            },
+        )
+        await create_tables()
+        logger.info("Database tables created successfully")
+
+        # Ensure initial admin user exists
+        from .database import AsyncSessionLocal
+        from .crud import ensure_initial_admin
+
+        async with AsyncSessionLocal() as db:
+            await ensure_initial_admin(db, settings.admin_initial_username)
+
+        yield
+
     # Create FastAPI instance
     app = FastAPI(
         title=settings.api_title,
         version=settings.api_version,
         docs_url="/api/docs",
         redoc_url="/api/redoc",
         openapi_url="/api/openapi.json",
+        lifespan=lifespan,
     )
 
     # Store dependencies in app state
@@ -133,35 +166,6 @@ async def log_requests(request: Request, call_next):
 
         return response
 
-    # Configure startup event
-    @app.on_event("startup")
-    async def startup_event():
-        # Configure logging using the app state
-        app.state.logging_manager.configure_logging()
-
-        # Disable uvicorn access logs to avoid duplication
-        uvicorn_logger = logging.getLogger("uvicorn.access")
-        uvicorn_logger.disabled = True
-
-        logger = get_logger("api.startup")
-        logger.info(
-            "Application starting up",
-            extra={
-                "log_level": settings.log_level,
-                "log_format": settings.log_format,
-                "api_version": settings.api_version,
-            },
-        )
-        await create_tables()
-        logger.info("Database tables created successfully")
-
-        # Ensure initial admin user exists
-        from .database import AsyncSessionLocal
-        from .crud import ensure_initial_admin
-
-        async with AsyncSessionLocal() as db:
-            await ensure_initial_admin(db, settings.admin_initial_username)
-
     # Include routers
     app.include_router(health.router)
     app.include_router(commits.router)

backend/app/logging_utils.py

@@ -1,7 +1,7 @@
 """Logging utilities for sanitizing sensitive data."""
 
 import re
-from typing import Any, Dict, List, Union
+from typing import Any, Dict, List
 
 # Patterns for sensitive data
 SENSITIVE_PATTERNS = [