From 40f7da6c3980e45bc8492a2843ee8b957f6e27af Mon Sep 17 00:00:00 2001
From: Neil Alexander <neilalexander@users.noreply.github.com>
Date: Fri, 22 May 2020 11:25:10 +0100
Subject: [PATCH] Set up prefixes properly

---
 internal/basecomponent/base.go |  5 +++--
 internal/httpapi.go            | 12 +++++++++---
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/internal/basecomponent/base.go b/internal/basecomponent/base.go
index f75faf044..0682ae0ea 100644
--- a/internal/basecomponent/base.go
+++ b/internal/basecomponent/base.go
@@ -96,14 +96,15 @@ func NewBaseDendrite(cfg *config.Dendrite, componentName string, enableHTTPAPIs
 		logrus.WithError(err).Warnf("Failed to create cache")
 	}
 
+	httpmux := mux.NewRouter()
 	return &BaseDendrite{
 		componentName:  componentName,
 		EnableHTTPAPIs: enableHTTPAPIs,
 		tracerCloser:   closer,
 		Cfg:            cfg,
 		ImmutableCache: cache,
-		PublicAPIMux:   mux.NewRouter().UseEncodedPath(),
-		InternalAPIMux: mux.NewRouter().UseEncodedPath(),
+		PublicAPIMux:   httpmux.PathPrefix(internal.HTTPPublicPathPrefix).Subrouter().UseEncodedPath(),
+		InternalAPIMux: httpmux.PathPrefix(internal.HTTPInternalPathPrefix).Subrouter().UseEncodedPath(),
 		httpClient:     &http.Client{Timeout: HTTPClientTimeout},
 		KafkaConsumer:  kafkaConsumer,
 		KafkaProducer:  kafkaProducer,
diff --git a/internal/httpapi.go b/internal/httpapi.go
index 0d50ff932..526ff8a2d 100644
--- a/internal/httpapi.go
+++ b/internal/httpapi.go
@@ -9,6 +9,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/gorilla/mux"
 	"github.com/matrix-org/dendrite/clientapi/auth"
 	"github.com/matrix-org/dendrite/clientapi/auth/authtypes"
 	"github.com/matrix-org/dendrite/internal/config"
@@ -22,6 +23,11 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+const (
+	HTTPPublicPathPrefix   = "/_matrix/"
+	HTTPInternalPathPrefix = "/api/"
+)
+
 // BasicAuth is used for authorization on /metrics handlers
 type BasicAuth struct {
 	Username string `yaml:"username"`
@@ -184,14 +190,14 @@ func MakeFedAPI(
 
 // SetupHTTPAPI registers an HTTP API mux under /api and sets up a metrics
 // listener.
-func SetupHTTPAPI(servMux *http.ServeMux, publicApiMux http.Handler, internalApiMux http.Handler, cfg *config.Dendrite, enableHTTPAPIs bool) {
+func SetupHTTPAPI(servMux *http.ServeMux, publicApiMux *mux.Router, internalApiMux *mux.Router, cfg *config.Dendrite, enableHTTPAPIs bool) {
 	if cfg.Metrics.Enabled {
 		servMux.Handle("/metrics", WrapHandlerInBasicAuth(promhttp.Handler(), cfg.Metrics.BasicAuth))
 	}
 	if enableHTTPAPIs {
-		servMux.Handle("/api", internalApiMux)
+		servMux.Handle(HTTPInternalPathPrefix, internalApiMux)
 	}
-	servMux.Handle("/_matrix", WrapHandlerInCORS(publicApiMux))
+	servMux.Handle(HTTPPublicPathPrefix, WrapHandlerInCORS(publicApiMux))
 }
 
 // WrapHandlerInBasicAuth adds basic auth to a handler. Only used for /metrics