[milo] fix raw annotation stream rendering endpoint.

milo/appengine/logdog/html.go

 // Copyright 2016 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 logdog
 
 import (
         "net/http"
         "strings"
 
@@ skipping 18 matching lines @@
 // temporarily (if incomplete) or indefinitely (if complete).
 type AnnotationStreamHandler struct{}
 
 func BuildHandler(c *router.Context) {
         (&AnnotationStreamHandler{}).Render(c)
         return
 }
 
 // Render implements settings.ThemedHandler.
 func (s *AnnotationStreamHandler) Render(c *router.Context) {
-
         as := AnnotationStream{
                 Project: cfgtypes.ProjectName(c.Params.ByName("project")),
                 Path:    types.StreamPath(strings.Trim(c.Params.ByName("path"), "/")),
         }
         if err := as.Normalize(); err != nil {
                 common.ErrorPage(c, http.StatusBadRequest, err.Error())
                 return
         }
 
         // Setup our LogDog client.
         var err error
-        if as.Client, err = NewClient(c.Context, ""); err != nil {
+        host := strings.TrimSpace(c.Params.ByName("logdog_host"))
+        if as.Client, err = NewClient(c.Context, host); err != nil {
                 log.WithError(err).Errorf(c.Context, "Failed to generate LogDog client.")
                 common.ErrorPage(c, http.StatusInternalServerError, "Failed to generate LogDog client")
                 return
         }
 
         // Load the Milo annotation protobuf from the annotation stream.
         if _, err := as.Fetch(c.Context); err != nil {
                 switch errors.Unwrap(err) {
                 case coordinator.ErrNoSuchStream:
                         common.ErrorPage(c, http.StatusNotFound, "Stream does not exist")
@@ skipping 46 matching lines @@
         }
 
         // Setup our LogDog client.
         return coordinator.NewClient(&prpc.Client{
                 C: &http.Client{
                         Transport: t,
                 },
                 Host: host,
         }), nil
 }