第四章练习答案

练习 1：完整测试套件

import pytest
from fastapi.testclient import TestClient
from main import app

client = TestClient(app)

class TestUserAPI:
    
    def test_create_user(self):
        response = client.post("/users/", json={
            "email": "test@example.com",
            "username": "testuser",
            "password": "password123"
        })
        assert response.status_code == 201
        data = response.json()
        assert data["email"] == "test@example.com"
        assert "hashed_password" not in data
    
    def test_list_users(self):
        response = client.get("/users/")
        assert response.status_code == 200
        assert isinstance(response.json(), list)
    
    def test_get_user_not_found(self):
        response = client.get("/users/99999")
        assert response.status_code == 404
    
    @pytest.mark.parametrize("email,username,expected_status", [
        ("valid@example.com", "validuser", 201),
        ("invalid", "user", 422),
        ("a@b.com", "ab", 422),  # username too short
    ])
    def test_create_user_validation(self, email, username, expected_status):
        response = client.post("/users/", json={
            "email": email,
            "username": username,
            "password": "password123"
        })
        assert response.status_code == expected_status

练习 2：CI/CD 配置

.github/workflows/test.yml：

name: Tests

on:
  push:
    branches: [ main ]
  pull_request:
    branches: [ main ]

jobs:
  test:
    runs-on: ubuntu-latest
    
    services:
      postgres:
        image: postgres:15
        env:
          POSTGRES_PASSWORD: postgres
        options: >-
          --health-cmd pg_isready
          --health-interval 10s
          --health-timeout 5s
          --health-retries 5
    
    steps:
    - uses: actions/checkout@v3
    
    - name: Set up Python
      uses: actions/setup-python@v4
      with:
        python-version: '3.11'
    
    - name: Install dependencies
      run: |
        pip install -r requirements.txt
        pip install pytest pytest-cov
    
    - name: Run tests
      run: |
        pytest --cov=. --cov-report=xml
    
    - name: Upload coverage
      uses: codecov/codecov-action@v3

练习 3：Docker Compose 完整栈

version: '3.8'

services:
  web:
    build:
      context: .
      dockerfile: Dockerfile
    command: gunicorn main:app --workers 4 --worker-class uvicorn.workers.UvicornWorker --bind 0.0.0.0:8000
    ports:
      - "8000:8000"
    environment:
      - DATABASE_URL=postgresql://postgres:postgres@db:5432/fastapi
      - REDIS_URL=redis://redis:6379
      - SECRET_KEY=${SECRET_KEY}
    depends_on:
      db:
        condition: service_healthy
      redis:
        condition: service_started
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:8000/health"]
      interval: 30s
      timeout: 10s
      retries: 3

  db:
    image: postgres:15
    environment:
      - POSTGRES_PASSWORD=postgres
      - POSTGRES_DB=fastapi
    volumes:
      - postgres_data:/var/lib/postgresql/data
    ports:
      - "5432:5432"
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U postgres"]
      interval: 10s
      timeout: 5s
      retries: 5

  redis:
    image: redis:7-alpine
    ports:
      - "6379:6379"
    volumes:
      - redis_data:/data

  nginx:
    image: nginx:alpine
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
      - ./ssl:/etc/nginx/ssl:ro
    depends_on:
      - web

volumes:
  postgres_data:
  redis_data:

返回第四章概览