Make HTTP middleware easier to use

appengine/gaemiddleware/context.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 gaemiddleware
 
 import (
         "net/http"
 
         "google.golang.org/appengine"
 
-        "github.com/julienschmidt/httprouter"
         "golang.org/x/net/context"
 
         "github.com/luci/gae/filter/dscache"
         "github.com/luci/gae/impl/prod"
         "github.com/luci/luci-go/appengine/gaeauth/client"
         "github.com/luci/luci-go/appengine/gaeauth/server"
         "github.com/luci/luci-go/appengine/gaeauth/server/gaesigner"
         "github.com/luci/luci-go/appengine/gaesecrets"
         "github.com/luci/luci-go/appengine/gaesettings"
         "github.com/luci/luci-go/appengine/tsmon"
         "github.com/luci/luci-go/common/cacheContext"
         "github.com/luci/luci-go/common/logging"
         "github.com/luci/luci-go/server/auth"
         "github.com/luci/luci-go/server/middleware"
         "github.com/luci/luci-go/server/proccache"
+        "github.com/luci/luci-go/server/router"
         "github.com/luci/luci-go/server/settings"
 )
 
 var (
         // globalProcessCache holds state cached between requests.
         globalProcessCache = &proccache.Cache{}
 
         // globalSettings holds global app settings lazily updated from the datastore.
         globalSettings = settings.New(gaesettings.Storage{})
 
@@ skipping 33 matching lines @@
         c = gaesecrets.Use(c, nil)
         c = gaesigner.Use(c)
         c = auth.UseDB(c, globalAuthDBCache)
         return cacheContext.Wrap(c)
 }
 
 // BaseProd adapts a middleware-style handler to a httprouter.Handle.
 //
 // It installs services using WithProd, installs a panic catcher if this
 // is not a devserver, and injects the monitoring middleware.
-func BaseProd(h middleware.Handler) httprouter.Handle {
-        h = globalTsMonState.Middleware(h)
+func BaseProd() []router.Handler {
+        var h []router.Handler
+        h = append(h, func(c *router.Context) {
+                c.Context = WithProd(context.Background(), c.Request)
+        })
         if !appengine.IsDevAppServer() {
-                h = middleware.WithPanicCatcher(h)
+                h = append(h, middleware.WithPanicCatcher())
         }
-        return func(rw http.ResponseWriter, r *http.Request, p httprouter.Params) {
-                h(WithProd(context.Background(), r), rw, r, p)
-        }
+        h = append(h, globalTsMonState.Middleware())
+        return h
 }