速率限制

RateLimiter 提供速率限制中间件，用于限制特定 IP 或标识符在一段时间内发送到服务器的请求数量。

默认情况下，请求记录保存在内存 store 中。默认内存实现专注于正确性，对于大量并发请求或大量不同标识符（>16k）可能不是最佳选择。

用法

要为应用添加速率限制，请添加 RateLimiter 中间件。下面的示例使用默认内存 store，将应用限制为 20 requests/sec：

e.Use(middleware.RateLimiter(middleware.NewRateLimiterMemoryStore(20.0)))

自定义配置

config := middleware.RateLimiterConfig{
  Skipper: middleware.DefaultSkipper,
  Store: middleware.NewRateLimiterMemoryStoreWithConfig(
    middleware.RateLimiterMemoryStoreConfig{Rate: 10, Burst: 30, ExpiresIn: 3 * time.Minute},
  ),
  IdentifierExtractor: func(c *echo.Context) (string, error) {
    id := c.RealIP()
    return id, nil
  },
  ErrorHandler: func(c *echo.Context, err error) error {
    return c.JSON(http.StatusForbidden, nil)
  },
  DenyHandler: func(c *echo.Context, identifier string, err error) error {
    return c.JSON(http.StatusTooManyRequests, nil)
  },
}

e.Use(middleware.RateLimiterWithConfig(config))

错误

var (
  // ErrRateLimitExceeded denotes an error raised when the rate limit is exceeded.
  ErrRateLimitExceeded = echo.NewHTTPError(http.StatusTooManyRequests, "rate limit exceeded")
  // ErrExtractorError denotes an error raised when the extractor function is unsuccessful.
  ErrExtractorError = echo.NewHTTPError(http.StatusForbidden, "error while extracting identifier")
)

配置

type RateLimiterConfig struct {
  Skipper    Skipper
  BeforeFunc BeforeFunc
  // IdentifierExtractor uses echo.Context to extract the identifier for a visitor.
  IdentifierExtractor Extractor
  // Store defines a store for the rate limiter.
  Store RateLimiterStore
  // ErrorHandler provides a handler to be called when IdentifierExtractor returns a non-nil error.
  ErrorHandler func(c *echo.Context, err error) error
  // DenyHandler provides a handler to be called when RateLimiter denies access.
  DenyHandler func(c *echo.Context, identifier string, err error) error
}

默认配置

// DefaultRateLimiterConfig defines default values for RateLimiterConfig.
var DefaultRateLimiterConfig = RateLimiterConfig{
  Skipper: DefaultSkipper,
  IdentifierExtractor: func(c *echo.Context) (string, error) {
    id := c.RealIP()
    return id, nil
  },
  ErrorHandler: func(c *echo.Context, err error) error {
    return &echo.HTTPError{
      Code:     ErrExtractorError.Code,
      Message:  ErrExtractorError.Message,
      Internal: err,
    }
  },
  DenyHandler: func(c *echo.Context, identifier string, err error) error {
    return &echo.HTTPError{
      Code:     ErrRateLimitExceeded.Code,
      Message:  ErrRateLimitExceeded.Message,
      Internal: err,
    }
  },
}