Fix regex with PathStrip

middlewares/stripPrefixRegex.go

@@ -0,0 +1,54 @@
+package middlewares
+
+import (
+	"net/http"
+
+	"github.com/containous/mux"
+	"github.com/containous/traefik/log"
+)
+
+// StripPrefixRegex is a middleware used to strip prefix from an URL request
+type StripPrefixRegex struct {
+	Handler http.Handler
+	router  *mux.Router
+}
+
+// NewStripPrefixRegex builds a new StripPrefixRegex given a handler and prefixes
+func NewStripPrefixRegex(handler http.Handler, prefixes []string) *StripPrefixRegex {
+	stripPrefix := StripPrefixRegex{Handler: handler, router: mux.NewRouter()}
+
+	for _, prefix := range prefixes {
+		stripPrefix.router.PathPrefix(prefix)
+	}
+
+	return &stripPrefix
+}
+
+func (s *StripPrefixRegex) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	var match mux.RouteMatch
+	if s.router.Match(r, &match) {
+		params := make([]string, 0, len(match.Vars)*2)
+		for key, val := range match.Vars {
+			params = append(params, key)
+			params = append(params, val)
+		}
+
+		prefix, err := match.Route.URL(params...)
+		if err != nil || len(prefix.Path) > len(r.URL.Path) {
+			log.Error("Error in stripPrefix middleware", err)
+			return
+		}
+
+		r.URL.Path = r.URL.Path[len(prefix.Path):]
+		r.Header[forwardedPrefixHeader] = []string{prefix.Path}
+		r.RequestURI = r.URL.RequestURI()
+		s.Handler.ServeHTTP(w, r)
+		return
+	}
+	http.NotFound(w, r)
+}
+
+// SetHandler sets handler
+func (s *StripPrefixRegex) SetHandler(Handler http.Handler) {
+	s.Handler = Handler
+}

middlewares/stripPrefixRegex_test.go

@@ -0,0 +1,55 @@
+package middlewares
+
+import (
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+func TestStripPrefixRegex(t *testing.T) {
+
+	handlerPath := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		fmt.Fprint(w, r.URL.Path)
+	})
+
+	handler := NewStripPrefixRegex(handlerPath, []string{"/a/api/", "/b/{regex}/", "/c/{category}/{id:[0-9]+}/"})
+	server := httptest.NewServer(handler)
+	defer server.Close()
+
+	tests := []struct {
+		expectedCode     int
+		expectedResponse string
+		url              string
+	}{
+		{url: "/a/test", expectedCode: 404, expectedResponse: "404 page not found\n"},
+		{url: "/a/api/test", expectedCode: 200, expectedResponse: "test"},
+
+		{url: "/b/api/", expectedCode: 200, expectedResponse: ""},
+		{url: "/b/api/test1", expectedCode: 200, expectedResponse: "test1"},
+		{url: "/b/api2/test2", expectedCode: 200, expectedResponse: "test2"},
+
+		{url: "/c/api/123/", expectedCode: 200, expectedResponse: ""},
+		{url: "/c/api/123/test3", expectedCode: 200, expectedResponse: "test3"},
+		{url: "/c/api/abc/test4", expectedCode: 404, expectedResponse: "404 page not found\n"},
+	}
+
+	for _, test := range tests {
+		resp, err := http.Get(server.URL + test.url)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if resp.StatusCode != test.expectedCode {
+			t.Fatalf("Received non-%d response: %d\n", test.expectedCode, resp.StatusCode)
+		}
+		response, err := ioutil.ReadAll(resp.Body)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if test.expectedResponse != string(response) {
+			t.Errorf("Expected '%s' :  '%s'\n", test.expectedResponse, response)
+		}
+	}
+
+}