Move code to pkg

pkg/server/service/proxy.go

@@ -0,0 +1,100 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+	"time"
+
+	"github.com/containous/flaeg/parse"
+	"github.com/containous/traefik/pkg/config"
+	"github.com/containous/traefik/pkg/log"
+)
+
+// StatusClientClosedRequest non-standard HTTP status code for client disconnection
+const StatusClientClosedRequest = 499
+
+// StatusClientClosedRequestText non-standard HTTP status for client disconnection
+const StatusClientClosedRequestText = "Client Closed Request"
+
+func buildProxy(passHostHeader bool, responseForwarding *config.ResponseForwarding, defaultRoundTripper http.RoundTripper, bufferPool httputil.BufferPool, responseModifier func(*http.Response) error) (http.Handler, error) {
+	var flushInterval parse.Duration
+	if responseForwarding != nil {
+		err := flushInterval.Set(responseForwarding.FlushInterval)
+		if err != nil {
+			return nil, fmt.Errorf("error creating flush interval: %v", err)
+		}
+	}
+	if flushInterval == 0 {
+		flushInterval = parse.Duration(100 * time.Millisecond)
+	}
+
+	proxy := &httputil.ReverseProxy{
+		Director: func(outReq *http.Request) {
+			u := outReq.URL
+			if outReq.RequestURI != "" {
+				parsedURL, err := url.ParseRequestURI(outReq.RequestURI)
+				if err == nil {
+					u = parsedURL
+				}
+			}
+
+			outReq.URL.Path = u.Path
+			outReq.URL.RawPath = u.RawPath
+			outReq.URL.RawQuery = u.RawQuery
+			outReq.RequestURI = "" // Outgoing request should not have RequestURI
+
+			outReq.Proto = "HTTP/1.1"
+			outReq.ProtoMajor = 1
+			outReq.ProtoMinor = 1
+
+			// Do not pass client Host header unless optsetter PassHostHeader is set.
+			if !passHostHeader {
+				outReq.Host = outReq.URL.Host
+			}
+
+		},
+		Transport:      defaultRoundTripper,
+		FlushInterval:  time.Duration(flushInterval),
+		ModifyResponse: responseModifier,
+		BufferPool:     bufferPool,
+		ErrorHandler: func(w http.ResponseWriter, request *http.Request, err error) {
+			statusCode := http.StatusInternalServerError
+
+			switch {
+			case err == io.EOF:
+				statusCode = http.StatusBadGateway
+			case err == context.Canceled:
+				statusCode = StatusClientClosedRequest
+			default:
+				if e, ok := err.(net.Error); ok {
+					if e.Timeout() {
+						statusCode = http.StatusGatewayTimeout
+					} else {
+						statusCode = http.StatusBadGateway
+					}
+				}
+			}
+
+			log.Debugf("'%d %s' caused by: %v", statusCode, statusText(statusCode), err)
+			w.WriteHeader(statusCode)
+			_, werr := w.Write([]byte(statusText(statusCode)))
+			if werr != nil {
+				log.Debugf("Error while writing status code", werr)
+			}
+		},
+	}
+
+	return proxy, nil
+}
+
+func statusText(statusCode int) string {
+	if statusCode == StatusClientClosedRequest {
+		return StatusClientClosedRequestText
+	}
+	return http.StatusText(statusCode)
+}