.circleci/config.yml

@@ -8,23 +8,35 @@ jobs:
       - image: circleci/golang:latest
     working_directory: /go/src/github.com/gorilla/mux
     steps: &steps
+      # Our build steps: we checkout the repo, fetch our deps, lint, and finally
+      # run "go test" on the package.
       - checkout
+      # Logs the version in our build logs, for posterity
       - run: go version
-      - run: go get -t -v ./...
+      - run:
+          name: "Fetch dependencies"
+          command: >
+            go get -t -v ./...
       # Only run gofmt, vet & lint against the latest Go version
-      - run: >
-          if [[ "$LATEST" = true ]]; then
-            go get -u golang.org/x/lint/golint
-            golint ./...
-          fi
-      - run: >
-          if [[ "$LATEST" = true ]]; then
-            diff -u <(echo -n) <(gofmt -d .)
-          fi
-      - run: >
-          if [[ "$LATEST" = true ]]; then
-            go vet -v .
-          fi
+      - run:
+          name: "Run golint"
+          command: >
+            if [ "${LATEST}" = true ] && [ -z "${SKIP_GOLINT}" ]; then
+              go get -u golang.org/x/lint/golint
+              golint ./...
+            fi
+      - run:
+          name: "Run gofmt"
+          command: >
+            if [[ "${LATEST}" = true ]]; then
+              diff -u <(echo -n) <(gofmt -d -e .)
+            fi
+      - run:
+          name: "Run go vet"
+          command:  >
+            if [[ "${LATEST}" = true ]]; then
+              go vet -v ./...
+            fi
       - run: go test -v -race ./...
 
   "latest":

README.md

@@ -1,11 +1,10 @@
 # gorilla/mux
 
 [![GoDoc](https://godoc.org/github.com/gorilla/mux?status.svg)](https://godoc.org/github.com/gorilla/mux)
-[![Build Status](https://travis-ci.org/gorilla/mux.svg?branch=master)](https://travis-ci.org/gorilla/mux)
 [![CircleCI](https://circleci.com/gh/gorilla/mux.svg?style=svg)](https://circleci.com/gh/gorilla/mux)
 [![Sourcegraph](https://sourcegraph.com/github.com/gorilla/mux/-/badge.svg)](https://sourcegraph.com/github.com/gorilla/mux?badge)
 
-![Gorilla Logo](http://www.gorillatoolkit.org/static/images/gorilla-icon-64.png)
+![Gorilla Logo](https://cloud-cdn.questionable.services/gorilla-icon-64.png)
 
 https://www.gorillatoolkit.org/pkg/mux
 
@@ -26,6 +25,7 @@ The name mux stands for "HTTP request multiplexer". Like the standard `http.Serv
 * [Examples](#examples)
 * [Matching Routes](#matching-routes)
 * [Static Files](#static-files)
+* [Serving Single Page Applications](#serving-single-page-applications) (e.g. React, Vue, Ember.js, etc.)
 * [Registered URLs](#registered-urls)
 * [Walking Routes](#walking-routes)
 * [Graceful Shutdown](#graceful-shutdown)
@@ -212,6 +212,93 @@ func main() {
 }
 ```
 
+### Serving Single Page Applications
+
+Most of the time it makes sense to serve your SPA on a separate web server from your API,
+but sometimes it's desirable to serve them both from one place. It's possible to write a simple
+handler for serving your SPA (for use with React Router's [BrowserRouter](https://reacttraining.com/react-router/web/api/BrowserRouter) for example), and leverage
+mux's powerful routing for your API endpoints.
+
+```go
+package main
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/gorilla/mux"
+)
+
+// spaHandler implements the http.Handler interface, so we can use it
+// to respond to HTTP requests. The path to the static directory and
+// path to the index file within that static directory are used to
+// serve the SPA in the given static directory.
+type spaHandler struct {
+	staticPath string
+	indexPath  string
+}
+
+// ServeHTTP inspects the URL path to locate a file within the static dir
+// on the SPA handler. If a file is found, it will be served. If not, the
+// file located at the index path on the SPA handler will be served. This
+// is suitable behavior for serving an SPA (single page application).
+func (h spaHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+    // get the absolute path to prevent directory traversal
+	path, err := filepath.Abs(r.URL.Path)
+	if err != nil {
+        // if we failed to get the absolute path respond with a 400 bad request
+        // and stop
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+    // prepend the path with the path to the static directory
+	path = filepath.Join(h.staticPath, path)
+
+    // check whether a file exists at the given path
+	_, err = os.Stat(path)
+	if os.IsNotExist(err) {
+		// file does not exist, serve index.html
+		http.ServeFile(w, r, filepath.Join(h.staticPath, h.indexPath))
+		return
+	} else if err != nil {
+        // if we got an error (that wasn't that the file doesn't exist) stating the
+        // file, return a 500 internal server error and stop
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+    // otherwise, use http.FileServer to serve the static dir
+	http.FileServer(http.Dir(h.staticPath)).ServeHTTP(w, r)
+}
+
+func main() {
+	router := mux.NewRouter()
+
+	router.HandleFunc("/api/health", func(w http.ResponseWriter, r *http.Request) {
+		// an example API handler
+		json.NewEncoder(w).Encode(map[string]bool{"ok": true})
+	})
+
+	spa := spaHandler{staticPath: "build", indexPath: "index.html"}
+	router.PathPrefix("/").Handler(spa)
+
+	srv := &http.Server{
+		Handler: router,
+		Addr:    "127.0.0.1:8000",
+		// Good practice: enforce timeouts for servers you create!
+		WriteTimeout: 15 * time.Second,
+		ReadTimeout:  15 * time.Second,
+	}
+
+	log.Fatal(srv.ListenAndServe())
+}
+```
+
 ### Registered URLs
 
 Now let's see how to build registered URLs.

go.mod

@@ -1 +1,3 @@
 module github.com/gorilla/mux
+
+go 1.12

middleware.go

@@ -58,22 +58,17 @@ func CORSMethodMiddleware(r *Router) MiddlewareFunc {
 func getAllMethodsForRoute(r *Router, req *http.Request) ([]string, error) {
 	var allMethods []string
 
-	err := r.Walk(func(route *Route, _ *Router, _ []*Route) error {
-		for _, m := range route.matchers {
-			if _, ok := m.(*routeRegexp); ok {
-				if m.Match(req, &RouteMatch{}) {
-					methods, err := route.GetMethods()
-					if err != nil {
-						return err
-					}
-
-					allMethods = append(allMethods, methods...)
-				}
-				break
+	for _, route := range r.routes {
+		var match RouteMatch
+		if route.Match(req, &match) || match.MatchErr == ErrMethodMismatch {
+			methods, err := route.GetMethods()
+			if err != nil {
+				return nil, err
 			}
+
+			allMethods = append(allMethods, methods...)
 		}
-		return nil
-	})
+	}
 
-	return allMethods, err
+	return allMethods, nil
 }

middleware_test.go

@@ -478,6 +478,26 @@ func TestCORSMethodMiddleware(t *testing.T) {
 	}
 }
 
+func TestCORSMethodMiddlewareSubrouter(t *testing.T) {
+	router := NewRouter().StrictSlash(true)
+
+	subrouter := router.PathPrefix("/test").Subrouter()
+	subrouter.HandleFunc("/hello", stringHandler("a")).Methods(http.MethodGet, http.MethodOptions, http.MethodPost)
+	subrouter.HandleFunc("/hello/{name}", stringHandler("b")).Methods(http.MethodGet, http.MethodOptions)
+
+	subrouter.Use(CORSMethodMiddleware(subrouter))
+
+	rw := NewRecorder()
+	req := newRequest("GET", "/test/hello/asdf")
+	router.ServeHTTP(rw, req)
+
+	actualMethods := rw.Header().Get("Access-Control-Allow-Methods")
+	expectedMethods := "GET,OPTIONS"
+	if actualMethods != expectedMethods {
+		t.Fatalf("expected methods %q but got: %q", expectedMethods, actualMethods)
+	}
+}
+
 func TestMiddlewareOnMultiSubrouter(t *testing.T) {
 	first := "first"
 	second := "second"

mux.go

@@ -5,6 +5,7 @@
 package mux
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"net/http"
@@ -58,8 +59,7 @@ type Router struct {
 
 	// If true, do not clear the request context after handling the request.
 	//
-	// Deprecated: No effect when go1.7+ is used, since the context is stored
-	// on the request itself.
+	// Deprecated: No effect, since the context is stored on the request itself.
 	KeepContext bool
 
 	// Slice of middlewares to be called after a match is found
@@ -111,10 +111,8 @@ func copyRouteConf(r routeConf) routeConf {
 		c.regexp.queries = append(c.regexp.queries, copyRouteRegexp(q))
 	}
 
-	c.matchers = make([]matcher, 0, len(r.matchers))
-	for _, m := range r.matchers {
-		c.matchers = append(c.matchers, m)
-	}
+	c.matchers = make([]matcher, len(r.matchers))
+	copy(c.matchers, r.matchers)
 
 	return c
 }
@@ -197,8 +195,8 @@ func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	var handler http.Handler
 	if r.Match(req, &match) {
 		handler = match.Handler
-		req = setVars(req, match.Vars)
-		req = setCurrentRoute(req, match.Route)
+		req = requestWithVars(req, match.Vars)
+		req = requestWithRoute(req, match.Route)
 	}
 
 	if handler == nil && match.MatchErr == ErrMethodMismatch {
@@ -428,7 +426,7 @@ const (
 
 // Vars returns the route variables for the current request, if any.
 func Vars(r *http.Request) map[string]string {
-	if rv := contextGet(r, varsKey); rv != nil {
+	if rv := r.Context().Value(varsKey); rv != nil {
 		return rv.(map[string]string)
 	}
 	return nil
@@ -440,18 +438,20 @@ func Vars(r *http.Request) map[string]string {
 // after the handler returns, unless the KeepContext option is set on the
 // Router.
 func CurrentRoute(r *http.Request) *Route {
-	if rv := contextGet(r, routeKey); rv != nil {
+	if rv := r.Context().Value(routeKey); rv != nil {
 		return rv.(*Route)
 	}
 	return nil
 }
 
-func setVars(r *http.Request, val interface{}) *http.Request {
-	return contextSet(r, varsKey, val)
+func requestWithVars(r *http.Request, vars map[string]string) *http.Request {
+	ctx := context.WithValue(r.Context(), varsKey, vars)
+	return r.WithContext(ctx)
 }
 
-func setCurrentRoute(r *http.Request, val interface{}) *http.Request {
-	return contextSet(r, routeKey, val)
+func requestWithRoute(r *http.Request, route *Route) *http.Request {
+	ctx := context.WithValue(r.Context(), routeKey, route)
+	return r.WithContext(ctx)
 }
 
 // ----------------------------------------------------------------------------