框架学习指南

本指南系统介绍后端开发中的框架学习知识点，适合初学者和进阶开发者。

目录

• Spring Boot
• Django/Flask
• 学习资源

---

Spring Boot

• 依赖注入

  @Service
  public class UserService {
      @Autowired
      private UserRepository userRepository;
  
      public User getUserById(Long id) {
          return userRepository.findById(id).orElse(null);
      }
  }

• AOP

  @Aspect
  @Component
  public class LoggingAspect {
      @Before("execution(* com.example.service.*.*(..))")
      public void logBefore(JoinPoint joinPoint) {
          System.out.println("Before method: " + joinPoint.getSignature().getName());
      }
  }

• 事务管理

  @Transactional
  public void updateUser(User user) {
      userRepository.save(user);
  }

• 安全框架

  @Configuration
  @EnableWebSecurity
  public class SecurityConfig extends WebSecurityConfigurerAdapter {
      @Override
      protected void configure(HttpSecurity http) throws Exception {
          http.authorizeRequests()
              .antMatchers("/public/**").permitAll()
              .anyRequest().authenticated()
              .and()
              .formLogin();
      }
  }

• 缓存集成

  @Cacheable(value = "users", key = "#id")
  public User getUserById(Long id) {
      return userRepository.findById(id).orElse(null);
  }

Django/Flask

• 路由系统

  # Django
  from django.urls import path
  from . import views
  
  urlpatterns = [
      path('users/', views.user_list),
      path('users/<int:user_id>/', views.user_detail),
  ]
  
  # Flask
  from flask import Flask
  
  app = Flask(__name__)
  
  @app.route('/users/')
  def user_list():
      return 'User List'
  
  @app.route('/users/<int:user_id>/')
  def user_detail(user_id):
      return f'User {user_id}'

• 模板引擎

  # Django
  from django.shortcuts import render
  
  def user_list(request):
      users = User.objects.all()
      return render(request, 'users/list.html', {'users': users})
  
  # Flask
  from flask import render_template
  
  @app.route('/users/')
  def user_list():
      users = User.query.all()
      return render_template('users/list.html', users=users)

• ORM

  # Django
  from django.db import models
  
  class User(models.Model):
      name = models.CharField(max_length=100)
      email = models.EmailField(unique=True)
  
  # Flask-SQLAlchemy
  from flask_sqlalchemy import SQLAlchemy
  
  db = SQLAlchemy()
  
  class User(db.Model):
      id = db.Column(db.Integer, primary_key=True)
      name = db.Column(db.String(100))
      email = db.Column(db.String(100), unique=True)

• 中间件

  # Django
  class LoggingMiddleware:
      def __init__(self, get_response):
          self.get_response = get_response
  
      def __call__(self, request):
          print(f"Request: {request.path}")
          response = self.get_response(request)
          print(f"Response: {response.status_code}")
          return response
  
  # Flask
  @app.before_request
  def before_request():
      print(f"Request: {request.path}")
  
  @app.after_request
  def after_request(response):
      print(f"Response: {response.status_code}")
      return response

• 认证系统

  # Django
  from django.contrib.auth.decorators import login_required
  
  @login_required
  def user_profile(request):
      return render(request, 'users/profile.html')
  
  # Flask
  from flask_login import login_required
  
  @app.route('/profile/')
  @login_required
  def user_profile():
      return render_template('users/profile.html')

学习资源

• Spring Boot 官方文档
• Django 官方文档
• Flask 官方文档
• 极客时间框架专栏

---

本文档持续完善中，欢迎补充与建议！