Add path option for proxying

server/proxy.go

@@ -24,7 +24,7 @@ type rewrite struct {
 }
 
 func (s *Server) Proxy(w http.ResponseWriter, r *http.Request) {
-	newURL, err := s.lookup(mapKey(r.Host))
+	newURL, err := s.lookup(mapKey(r, config.GetProxyMode()))
 	var transport http.RoundTripper
 	transport = &redirPurge{
 		proxyHost:     r.Host,
@@ -32,7 +32,7 @@ func (s *Server) Proxy(w http.ResponseWriter, r *http.Request) {
 		baseTransport: http.DefaultTransport,
 	}
 	transport = &rewrite{
-		rewrites:      config.GetRewrites(mapKey(r.Host)),
+		rewrites:      config.GetRewrites(mapKey(r, config.GetProxyMode())),
 		baseTransport: transport,
 	}
 	if err != nil {
@@ -52,10 +52,20 @@ func (s *Server) lookup(host string) (*url.URL, error) {
 	return v.URL(), err
 }
 
-func mapKey(host string) string {
-	host = strings.Split(host, ".")[0]
-	host = strings.Split(host, ":")[0]
-	return host
+func mapKey(r *http.Request, proxyMode string) string {
+	switch proxyMode {
+	case "domain":
+		host := strings.Split(r.Host, ".")[0]
+		host = strings.Split(host, ":")[0]
+		return host
+	case "path":
+		paths := strings.Split(r.URL.Path, "/")
+		if len(paths) < 2 {
+			return ""
+		}
+		return paths[1]
+	}
+	return ""
 }
 
 func (rp *redirPurge) RoundTrip(r *http.Request) (*http.Response, error) {

server/proxy_test.go

@@ -3,6 +3,7 @@ package server
 import (
 	"io/ioutil"
 	"net/http"
+	"net/url"
 	"strings"
 	"testing"
 )
@@ -40,3 +41,35 @@ func TestRewrite(t *testing.T) {
 		t.Errorf("failed to replace: got %q, want \"b\"", b)
 	}
 }
+
+func TestMapKey(t *testing.T) {
+	r := &http.Request{
+		Host: "a.b.c:123",
+		URL: &url.URL{
+			Path: "/c/d/e",
+		},
+	}
+
+	if v := mapKey(r, "domain"); v != "a" {
+		t.Errorf("failed to get domain: got %v", v)
+	}
+
+	if v := mapKey(r, "path"); v != "c" {
+		t.Errorf("failed to get domain: got %v", v)
+	}
+
+	r.Host = "a:123"
+	if v := mapKey(r, "domain"); v != "a" {
+		t.Errorf("failed to get domain: got %v", v)
+	}
+
+	r.URL.Path = ""
+	if v := mapKey(r, "path"); v != "" {
+		t.Errorf("failed to get domain: got %v", v)
+	}
+
+	r.URL.Path = "/"
+	if v := mapKey(r, "path"); v != "" {
+		t.Errorf("failed to get domain: got %v", v)
+	}
+}