Initial distributor implementation

appengine/cmd/dm/distributor/tq_handler.go

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package distributor
+
+import (
+        "net/http"
+        "net/url"
+        "strings"
+
+        "github.com/julienschmidt/httprouter"
+        "github.com/luci/luci-go/appengine/gaemiddleware"
+        "github.com/luci/luci-go/server/middleware"
+        "golang.org/x/net/context"
+)
+
+const handlerPattern = "/tq/distributor/:cfgName"
+
+func handlerPath(cfgName string) string {
+        return strings.Replace(handlerPattern, ":cfgName", url.QueryEscape(cfgName), 1)
+}
+
+// InstallHandlers installs the taskqueue callback handler.
+func InstallHandlers(r *httprouter.Router, base middleware.Base) {
+        r.POST(handlerPattern, base(
+                gaemiddleware.RequireTaskQueue("", taskqueHandler)))
+}
+
+func taskqueHandler(c context.Context, rw http.ResponseWriter, r *http.Request, p httprouter.Params) {
+        defer r.Body.Close()
+
+        cfg, err := LoadConfiguration(c, p.ByName("cfgName"))
+        if err != nil {
+                http.Error(rw, "bad configuration name", http.StatusBadRequest)
+                return
+        }
+        dist, err := MakeDistributor(c, cfg)
+        if err != nil {
+                http.Error(rw, "bad distributor", http.StatusBadRequest)
+                return
+        }
+        err = dist.HandleTaskQueueTask(c, r)
+        if err != nil {
+                http.Error(rw, "failure to execute handler", http.StatusInternalServerError)
+                return
+        }
+        rw.WriteHeader(http.StatusOK)
+}