1 files changed, 62 insertions, 0 deletions
diff --git a/workhorse/internal/proxy/proxy.go b/workhorse/internal/proxy/proxy.go
new file mode 100644
index 00000000000..1bc417a841f
--- /dev/null
+++ b/workhorse/internal/proxy/proxy.go
@@ -0,0 +1,62 @@
+package proxy
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+	"time"
+
+	"gitlab.com/gitlab-org/gitlab-workhorse/internal/helper"
+)
+
+var (
+	defaultTarget = helper.URLMustParse("http://localhost")
+)
+
+type Proxy struct {
+	Version                string
+	reverseProxy           *httputil.ReverseProxy
+	AllowResponseBuffering bool
+}
+
+func NewProxy(myURL *url.URL, version string, roundTripper http.RoundTripper) *Proxy {
+	p := Proxy{Version: version, AllowResponseBuffering: true}
+
+	if myURL == nil {
+		myURL = defaultTarget
+	}
+
+	u := *myURL // Make a copy of p.URL
+	u.Path = ""
+	p.reverseProxy = httputil.NewSingleHostReverseProxy(&u)
+	p.reverseProxy.Transport = roundTripper
+	return &p
+}
+
+func (p *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	// Clone request
+	req := *r
+	req.Header = helper.HeaderClone(r.Header)
+
+	// Set Workhorse version
+	req.Header.Set("Gitlab-Workhorse", p.Version)
+	req.Header.Set("Gitlab-Workhorse-Proxy-Start", fmt.Sprintf("%d", time.Now().UnixNano()))
+
+	if p.AllowResponseBuffering {
+		helper.AllowResponseBuffering(w)
+	}
+
+	// If the ultimate client disconnects when the response isn't fully written
+	// to them yet, httputil.ReverseProxy panics with a net/http.ErrAbortHandler
+	// error. We can catch and discard this to keep the error log clean
+	defer func() {
+		if err := recover(); err != nil {
+			if err != http.ErrAbortHandler {
+				panic(err)
+			}
+		}
+	}()
+
+	p.reverseProxy.ServeHTTP(w, &req)
+}