CORS (跨域资源共享) 中间件

CORS (Cross-origin resource sharing) 中间件实现了 CORS 的标准。CORS为Web服务器提供跨域访问控制，从而实现安全的跨域数据传输。

用法

  1. e.Use(middleware.CORS())

自定义配置

用法

  1. e := echo.New()
  2. e.Use(middleware.CORSWithConfig(middleware.CORSConfig{
  3.   AllowOrigins: []string{"https://labstack.com", "https://labstack.net"},
  4.   AllowHeaders: []string{echo.HeaderOrigin, echo.HeaderContentType, echo.HeaderAccept},
  5. }))

配置

  1. // CORSConfig defines the config for CORS middleware.
  2. CORSConfig struct {
  3.   // Skipper defines a function to skip middleware.
  4.   Skipper Skipper
  6.   // AllowOrigin defines a list of origins that may access the resource.
  7.   // Optional. Default value []string{"*"}.
  8.   AllowOrigins []string `json:"allow_origins"`
  10.   // AllowMethods defines a list methods allowed when accessing the resource.
  11.   // This is used in response to a preflight request.
  12.   // Optional. Default value DefaultCORSConfig.AllowMethods.
  13.   AllowMethods []string `json:"allow_methods"`
  15.   // AllowHeaders defines a list of request headers that can be used when
  16.   // making the actual request. This in response to a preflight request.
  17.   // Optional. Default value []string{}.
  18.   AllowHeaders []string `json:"allow_headers"`
  20.   // AllowCredentials indicates whether or not the response to the request
  21.   // can be exposed when the credentials flag is true. When used as part of
  22.   // a response to a preflight request, this indicates whether or not the
  23.   // actual request can be made using credentials.
  24.   // Optional. Default value false.
  25.   AllowCredentials bool `json:"allow_credentials"`
  27.   // ExposeHeaders defines a whitelist headers that clients are allowed to
  28.   // access.
  29.   // Optional. Default value []string{}.
  30.   ExposeHeaders []string `json:"expose_headers"`
  32.   // MaxAge indicates how long (in seconds) the results of a preflight request
  33.   // can be cached.
  34.   // Optional. Default value 0.
  35.   MaxAge int `json:"max_age"`
  36. }

默认配置

  1. DefaultCORSConfig = CORSConfig{
  2.   Skipper:      defaultSkipper,
  3.   AllowOrigins: []string{"*"},
  4.   AllowMethods: []string{echo.GET, echo.HEAD, echo.PUT, echo.PATCH, echo.POST, echo.DELETE},
  5. }