Make HTTP middleware easier to use

appengine/logdog/coordinator/service.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 coordinator
 
 import (
-        "net/http"
         "sync"
         "sync/atomic"
 
-        "github.com/julienschmidt/httprouter"
         gaeauthClient "github.com/luci/luci-go/appengine/gaeauth/client"
         "github.com/luci/luci-go/appengine/logdog/coordinator/config"
         luciConfig "github.com/luci/luci-go/common/config"
         "github.com/luci/luci-go/common/errors"
         "github.com/luci/luci-go/common/gcloud/gs"
         "github.com/luci/luci-go/common/gcloud/pubsub"
         log "github.com/luci/luci-go/common/logging"
         "github.com/luci/luci-go/common/proto/logdog/svcconfig"
         "github.com/luci/luci-go/server/logdog/storage"
         "github.com/luci/luci-go/server/logdog/storage/bigtable"
-        "github.com/luci/luci-go/server/middleware"
+        "github.com/luci/luci-go/server/router"
         "golang.org/x/net/context"
         "google.golang.org/cloud"
         gcps "google.golang.org/cloud/pubsub"
         "google.golang.org/grpc/metadata"
 )
 
 // Services is a set of support services used by Coordinator.
 //
 // Each Services instance is valid for a singel request, but can be re-used
 // throughout that request. This is advised, as the Services instance may
@@ skipping 22 matching lines @@
         // The caller must close the returned instance if successful.
         IntermediateStorage(context.Context) (storage.Storage, error)
 
         // GSClient instantiates a Google Storage client.
         GSClient(context.Context) (gs.Client, error)
 
         // ArchivalPublisher returns an ArchivalPublisher instance.
         ArchivalPublisher(context.Context) (ArchivalPublisher, error)
 }
 
-// WithProdServices is a middleware Handler that installs a production Services
+// WithProdServices is a middleware that installs a production Services
 // instance into its Context.
-func WithProdServices(h middleware.Handler) middleware.Handler {
-        return func(c context.Context, rw http.ResponseWriter, r *http.Request, params httprouter.Params) {
-                c = UseProdServices(c)
-                h(c, rw, r, params)
-        }
+func WithProdServices(c *router.Context, next router.Handler) {
+        c.Context = UseProdServices(c.Context)
+        next(c)
 }
 
 // UseProdServices installs production Services instance into the supplied
 // Context.
 func UseProdServices(c context.Context) context.Context {
         return WithServices(c, &prodServicesInst{})
 }
 
 // prodServicesInst is a Service exposing production faciliites. A unique
 // instance is bound to each each request.
@@ skipping 197 matching lines @@
         // value as a sentinel that the archival index has wrapped.
         //
         // This is reasonable, as it is very unlikely that a single request will issue
         // more than MaxInt32 archival tasks.
         v := atomic.AddInt32(&s.archivalIndex, 1) - 1
         if v < 0 {
                 panic("archival index has wrapped")
         }
         return uint64(v)
 }