CORS跨域资源共享控制

HTTP Dispatcher的入口路由组特性，可以很方便的开发一个CORS处理器并在入口路由组执行。

CORS处理函数

  1. //CORS配置
  2. type CORSconfig struct {
  3.     AllowOrigins     []string
  4.     ExposeHeaders    []string
  5.     AllowCredentials bool
  6.     AllowMethods     []string
  7.     AllowHeaders     []string
  8. }
  9.  
  10. //CORS处理器
  11. func CORSHandler(config *CORSconfig) httpdispatcher.Handler {
  12.     return func(ctx *httpdispatcher.Context) error {
  13.         if config.AllowOrigins != nil {
  14.             if config.AllowMethods[0] == "*" {
  15.                 ctx.ResponseWriter.Header().Set("Access-Control-Allow-Origin", "*")
  16.             } else {
  17.                 ctx.ResponseWriter.Header().Set("Access-Control-Allow-Origin", strings.Join(config.AllowOrigins, ","))
  18.             }
  19.         }
  20.         if config.AllowMethods != nil {
  21.             if config.AllowMethods[0] == "*" {
  22.                 ctx.ResponseWriter.Header().Set("Access-Control-Allow-Methods", "*")
  23.             } else {
  24.                 ctx.ResponseWriter.Header().Set("Access-Control-Allow-Methods", strings.Join(config.AllowMethods, ","))
  25.             }
  26.         }
  27.         if config.AllowHeaders != nil {
  28.             if config.AllowHeaders[0] == "*" {
  29.                 ctx.ResponseWriter.Header().Set("Access-Control-Allow-Headers", "*")
  30.             } else {
  31.                 ctx.ResponseWriter.Header().Set("Access-Control-Allow-Headers", strings.Join(config.AllowHeaders, ","))
  32.             }
  33.         }
  34.         if config.ExposeHeaders != nil {
  35.             if config.ExposeHeaders[0] == "*" {
  36.                 ctx.ResponseWriter.Header().Set("Access-Control-Expose-Headers", "*")
  37.             } else {
  38.                 ctx.ResponseWriter.Header().Set("Access-Control-Expose-Headers", strings.Join(config.ExposeHeaders, ","))
  39.             }
  40.         }
  41.         if config.ExposeHeaders != nil {
  42.             if config.ExposeHeaders[0] == "*" {
  43.                 ctx.ResponseWriter.Header().Set("Access-Control-Expose-Headers", "*")
  44.             } else {
  45.                 ctx.ResponseWriter.Header().Set("Access-Control-Expose-Headers", strings.Join(config.ExposeHeaders, ","))
  46.             }
  47.         }
  48.         if config.AllowCredentials == true {
  49.             ctx.ResponseWriter.Header().Set("Access-Control-Allow-Credentials", "true")
  50.         }
  51.         //继续执行路由函数
  52.         return ctx.Next(true)
  53.     }
  54. }

使用CORS处理器

  1. //获得一个调度器的实例化对象
  2. var dispatcher = httpdispatcher.New()
  3.  
  4. //定义CORS的配置
  5. var corsConfig CORSconfig
  6. corsConfig.AllowOrigins=[]string{"*"}
  7. corsConfig.AllowMethods=[]string{"*"}
  8. corsConfig.AllowHeaders=[]string{"*"}
  9. corsConfig.AllowCredentials=true
  10. corsConfig.ExposeHeaders=[]string{"*"}
  11.  
  12. //注册入口路由组，并传入CORS处理器
  13. router := dispatcher.Router.GROUP("", CORSHandler(&corsConfig))
  14.  
  15. //在路由组里注册路由，会自动执行CORS处理器
  16. router.GET("/", func(ctx *httpdispatcher.Context) error {
  17.     return nil
  18. })