adapter scheme header (#634)

pkg/context/httprequest.go

@@ -20,6 +20,7 @@ package context
 import (
  "io"
  "net/http"
+ "strings"
 
  "github.com/tomasen/realip"
 
@@ -38,6 +39,10 @@ type (
  }
 )
 
+const (
+ xForwardedProto = "X-Forwarded-Proto"
+)
+
 func newHTTPRequest(stdr *http.Request) *httpRequest {
  // Reference: https://golang.org/pkg/net/http/#Request
  //
@@ -96,8 +101,15 @@ func (r *httpRequest) Scheme() string {
  return scheme
  }
 
- if scheme := r.std.Header.Get("X-Forwarded-Proto"); scheme != "" {
- return scheme
+ if scheme := r.std.Header.Get(xForwardedProto); scheme != "" {
+ // note some proxy servers will append data in this format,
+ // and the last one is sent by the last proxy-server and should use for easegress's proxy
+ // header : {
+ // some-key: "ele1, ele2, ele3"
+ // }
+ // https://github.com/spring-cloud/spring-cloud-gateway/ ProxyExchange.java#appendXForwarded()
+ schemes := strings.Split(scheme, ",")
+ return schemes[len(schemes)-1]
  }
 
  if r.std.TLS != nil {