Make HTTP middleware easier to use

server/auth/handlers.go

 // Copyright 2015 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.
 
 package auth
 
 import (
         "encoding/json"
         "net/http"
 
-        "github.com/julienschmidt/httprouter"
-        "golang.org/x/net/context"
-
         "github.com/luci/luci-go/common/logging"
-        "github.com/luci/luci-go/server/middleware"
+        "github.com/luci/luci-go/server/router"
 )
 
 // InstallHandlers installs HTTP handlers that return information useful for
 // debugging authentication issues.
 //
 // This is optional. If you using appengine/gaeauth/server, these handlers are
 // already installed.
-func InstallHandlers(r *httprouter.Router, base middleware.Base) {
-        r.GET("/auth/api/v1/accounts/self", base(Authenticate(accountsSelfHandler)))
+func InstallHandlers(r *router.Router, base router.MiddlewareChain) {
+        mc := append(base, Authenticate)
+        r.GET("/auth/api/v1/accounts/self", mc, accountsSelfHandler)
 }
 
 // accountsSelfHandler returns JSON with information about the caller.
 //
 // It can be used to verify callers' IP, access tokens, etc.
-func accountsSelfHandler(c context.Context, rw http.ResponseWriter, r *http.Request, p httprouter.Params) {
+func accountsSelfHandler(c *router.Context) {
         var reply struct {
                 Error    string `json:"error,omitempty"`
                 Identity string `json:"identity,omitempty"`
                 IP       string `json:"ip,omitempty"`
         }
 
-        state := GetState(c)
+        state := GetState(c.Context)
         if state == nil {
                 reply.Error = "Auth state is not available, application is probably using auth library wrong."
         } else {
                 reply.Identity = string(state.User().Identity)
                 reply.IP = state.PeerIP().String()
         }
 
-        rw.Header().Set("Content-Type", "application/json; charset=utf-8")
+        c.Writer.Header().Set("Content-Type", "application/json; charset=utf-8")
         if reply.Error == "" {
-                rw.WriteHeader(http.StatusOK)
+                c.Writer.WriteHeader(http.StatusOK)
         } else {
-                rw.WriteHeader(http.StatusNotImplemented)
-                logging.Errorf(c, "HTTP 501 - %s", reply.Error)
+                c.Writer.WriteHeader(http.StatusNotImplemented)
+                logging.Errorf(c.Context, "HTTP 501 - %s", reply.Error)
         }
-        json.NewEncoder(rw).Encode(&reply)
+        json.NewEncoder(c.Writer).Encode(&reply)
 }