知识付费系统开发核心架构拆解：从内容管理到支付闭环实现

用户端（H5 / 小程序 / App）
        │
API网关层（鉴权、限流、日志）
        │
业务服务层
  ├── 用户服务
  ├── 内容服务
  ├── 订单服务
  ├── 支付服务
  ├── 会员服务
  └── 分销服务
        │
数据层（MySQL + Redis + 对象存储）

CREATE TABLE course (
  id BIGINT PRIMARY KEY AUTO_INCREMENT,
  title VARCHAR(255) NOT NULL,
  cover VARCHAR(500),
  price DECIMAL(10,2) NOT NULL,
  status TINYINT DEFAULT 1,
  created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

CREATE TABLE chapter (
  id BIGINT PRIMARY KEY AUTO_INCREMENT,
  course_id BIGINT NOT NULL,
  title VARCHAR(255),
  video_url VARCHAR(500),
  duration INT,
  sort_order INT,
  FOREIGN KEY (course_id) REFERENCES course(id)
);

public VideoAccessVO getVideoAccess(Long userId, Long chapterId) {

    boolean isVip = memberService.checkVip(userId);
    boolean isPurchased = orderService.checkCoursePurchased(userId, chapterId);

    if (!isVip && !isPurchased) {
        throw new BusinessException("未购买课程");
    }

    String tempUrl = storageService.generateSignedUrl(chapterId);

    return new VideoAccessVO(tempUrl);
}

CREATE TABLE orders (
  id BIGINT PRIMARY KEY AUTO_INCREMENT,
  user_id BIGINT NOT NULL,
  course_id BIGINT NOT NULL,
  order_no VARCHAR(64) UNIQUE,
  amount DECIMAL(10,2),
  status TINYINT DEFAULT 0,
  created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

public Order createOrder(Long userId, Long courseId) {

    Course course = courseService.getById(courseId);

    Order order = new Order();
    order.setUserId(userId);
    order.setCourseId(courseId);
    order.setAmount(course.getPrice());
    order.setOrderNo(generateOrderNo());

    orderMapper.insert(order);

    return order;
}

@PostMapping("/pay/notify")
public String payNotify(@RequestBody PayNotifyDTO dto) {

    boolean verified = payService.verifySign(dto);

    if (!verified) {
        return "fail";
    }

    Order order = orderService.getByOrderNo(dto.getOrderNo());

    if (order.getStatus() == 1) {
        return "success";
    }

    order.setStatus(1);
    orderService.update(order);

    return "success";
}

CREATE TABLE user_course (
  id BIGINT PRIMARY KEY AUTO_INCREMENT,
  user_id BIGINT,
  course_id BIGINT,
  created_at DATETIME DEFAULT CURRENT_TIMESTAMP
);

@Transactional
public void handlePaySuccess(Order order) {

    order.setStatus(1);
    orderMapper.update(order);

    UserCourse uc = new UserCourse();
    uc.setUserId(order.getUserId());
    uc.setCourseId(order.getCourseId());

    userCourseMapper.insert(uc);
}

String cacheKey = "course:" + courseId;
Course course = redisTemplate.opsForValue().get(cacheKey);

if (course == null) {
    course = courseMapper.selectById(courseId);
    redisTemplate.opsForValue().set(cacheKey, course, 10, TimeUnit.MINUTES);
}