Add prefetch UMA metrics.

components/precache/core/precache_fetcher_unittest.cc

 // Copyright 2013 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.
 
 #include "components/precache/core/precache_fetcher.h"
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
+#include "base/test/histogram_tester.h"
 #include "base/thread_task_runner_handle.h"
 #include "components/precache/core/precache_switches.h"
 #include "components/precache/core/proto/precache.pb.h"
 #include "net/http/http_response_headers.h"
 #include "net/http/http_status_code.h"
 #include "net/url_request/test_url_fetcher_factory.h"
 #include "net/url_request/url_request_status.h"
 #include "net/url_request/url_request_test_util.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace precache {
 
 namespace {
 
 class TestURLFetcherCallback {
  public:
+  TestURLFetcherCallback() : total_response_bytes_(0) {}
+
   scoped_ptr<net::FakeURLFetcher> CreateURLFetcher(
       const GURL& url, net::URLFetcherDelegate* delegate,
       const std::string& response_data, net::HttpStatusCode response_code,
       net::URLRequestStatus::Status status) {
     scoped_ptr<net::FakeURLFetcher> fetcher(new net::FakeURLFetcher(
         url, delegate, response_data, response_code, status));
 
     if (response_code == net::HTTP_OK) {
       scoped_refptr<net::HttpResponseHeaders> download_headers =
           new net::HttpResponseHeaders("");
       download_headers->AddHeader("Content-Type: text/html");
       fetcher->set_response_headers(download_headers);
     }
 
+    total_response_bytes_ += response_data.size();
     requested_urls_.insert(url);
     return fetcher.Pass();
   }
 
   const std::multiset<GURL>& requested_urls() const {
     return requested_urls_;
   }
 
+  int total_response_bytes() const { return total_response_bytes_; }
+
  private:
   // Multiset with one entry for each URL requested.
   std::multiset<GURL> requested_urls_;
+  int total_response_bytes_;
 };
 
 class TestPrecacheDelegate : public PrecacheFetcher::PrecacheDelegate {
  public:
   TestPrecacheDelegate() : was_on_done_called_(false) {}
 
   void OnDone() override { was_on_done_called_ = true; }
 
   bool was_on_done_called() const {
     return was_on_done_called_;
   }
 
  private:
   bool was_on_done_called_;
 };
 
 class PrecacheFetcherTest : public testing::Test {
  public:
   PrecacheFetcherTest()
       : request_context_(new net::TestURLRequestContextGetter(
             base::ThreadTaskRunnerHandle::Get())),
         factory_(NULL,
                  base::Bind(&TestURLFetcherCallback::CreateURLFetcher,
-                            base::Unretained(&url_callback_))) {}
+                            base::Unretained(&url_callback_))),
+        expected_total_response_bytes_(0) {}
 
  protected:
   base::MessageLoopForUI loop_;
   scoped_refptr<net::TestURLRequestContextGetter> request_context_;
   TestURLFetcherCallback url_callback_;
   net::FakeURLFetcherFactory factory_;
   TestPrecacheDelegate precache_delegate_;
+  int expected_total_response_bytes_;
 };
 
 const char kConfigURL[] = "http://config-url.com";
 const char kManifestURLPrefix[] = "http://manifest-url-prefix.com/";
 const char kCustomManifestURLPrefix[] =
     "http://custom-manifest-url-prefix.com/";
 const char kManifestFetchFailureURL[] =
     "http://manifest-url-prefix.com/manifest-fetch-failure.com";
 const char kBadManifestURL[] =
     "http://manifest-url-prefix.com/bad-manifest.com";
@@ skipping 41 matching lines @@
                            net::URLRequestStatus::SUCCESS);
   factory_.SetFakeResponse(GURL(kResourceFetchFailureURL),
                            "", net::HTTP_INTERNAL_SERVER_ERROR,
                            net::URLRequestStatus::FAILED);
   factory_.SetFakeResponse(GURL(kGoodResourceURL), "good", net::HTTP_OK,
                            net::URLRequestStatus::SUCCESS);
   factory_.SetFakeResponse(GURL(kForcedStartingURLManifestURL),
                            PrecacheManifest().SerializeAsString(), net::HTTP_OK,
                            net::URLRequestStatus::SUCCESS);
 
-  PrecacheFetcher precache_fetcher(starting_hosts, request_context_.get(),
-                                   std::string(), &precache_delegate_);
-  precache_fetcher.Start();
+  base::HistogramTester histogram;
 
-  base::MessageLoop::current()->RunUntilIdle();
+  {
+    PrecacheFetcher precache_fetcher(starting_hosts, request_context_.get(),
+                                     std::string(), &precache_delegate_);
+    precache_fetcher.Start();
+
+    base::MessageLoop::current()->RunUntilIdle();
+
+    // Destroy the PrecacheFetcher after it has finished, to record metrics.
+  }
 
   std::multiset<GURL> expected_requested_urls;
   expected_requested_urls.insert(GURL(kConfigURL));
   expected_requested_urls.insert(GURL(kManifestFetchFailureURL));
   expected_requested_urls.insert(GURL(kBadManifestURL));
   expected_requested_urls.insert(GURL(kGoodManifestURL));
   expected_requested_urls.insert(GURL(kResourceFetchFailureURL));
   expected_requested_urls.insert(GURL(kGoodResourceURL));
   expected_requested_urls.insert(GURL(kForcedStartingURLManifestURL));
 
   EXPECT_EQ(expected_requested_urls, url_callback_.requested_urls());
 
   EXPECT_TRUE(precache_delegate_.was_on_done_called());
+
+  histogram.ExpectUniqueSample("Precache.Fetch.PercentCompleted", 100, 1);
+  histogram.ExpectUniqueSample("Precache.Fetch.ResponseBytes",
+                               url_callback_.total_response_bytes(), 1);
 }
 
 TEST_F(PrecacheFetcherTest, CustomManifestURLPrefix) {
   base::CommandLine::ForCurrentProcess()->AppendSwitchASCII(
       switches::kPrecacheConfigSettingsURL, kConfigURL);
   base::CommandLine::ForCurrentProcess()->AppendSwitchASCII(
       switches::kPrecacheManifestURLPrefix, kManifestURLPrefix);
 
   std::vector<std::string> starting_hosts;
   starting_hosts.push_back("good-manifest.com");
@@ skipping 88 matching lines @@
       switches::kPrecacheConfigSettingsURL, kConfigURL);
 
   std::vector<std::string> starting_hosts(1, "starting-url.com");
 
   PrecacheConfigurationSettings config;
   config.set_top_sites_count(1);
 
   factory_.SetFakeResponse(GURL(kConfigURL), config.SerializeAsString(),
                            net::HTTP_OK, net::URLRequestStatus::SUCCESS);
 
-  scoped_ptr<PrecacheFetcher> precache_fetcher(
-      new PrecacheFetcher(starting_hosts, request_context_.get(), std::string(),
-                          &precache_delegate_));
-  precache_fetcher->Start();
+  base::HistogramTester histogram;
 
-  // Destroy the PrecacheFetcher to cancel precaching. This should not cause
-  // OnDone to be called on the precache delegate.
-  precache_fetcher.reset();
+  {
+    PrecacheFetcher precache_fetcher(starting_hosts, request_context_.get(),
+                                     std::string(), &precache_delegate_);
+    precache_fetcher.Start();
+
+    // Destroy the PrecacheFetcher, to cancel precaching and record metrics.
+    // This should not cause OnDone to be called on the precache delegate.
+  }
 
   base::MessageLoop::current()->RunUntilIdle();
 
   std::multiset<GURL> expected_requested_urls;
   expected_requested_urls.insert(GURL(kConfigURL));
   EXPECT_EQ(expected_requested_urls, url_callback_.requested_urls());
 
   EXPECT_FALSE(precache_delegate_.was_on_done_called());
+
+  histogram.ExpectUniqueSample("Precache.Fetch.PercentCompleted", 0, 1);
+  histogram.ExpectUniqueSample("Precache.Fetch.ResponseBytes", 0, 1);
 }
 
 #if defined(PRECACHE_CONFIG_SETTINGS_URL)
 
 // If the default precache configuration settings URL is defined, then test that
 // it works with the PrecacheFetcher.
 TEST_F(PrecacheFetcherTest, PrecacheUsingDefaultConfigSettingsURL) {
   std::vector<std::string> starting_hosts(1, "starting-url.com");
 
   PrecacheConfigurationSettings config;
@@ skipping 50 matching lines @@
   EXPECT_EQ(expected_requested_urls, url_callback_.requested_urls());
 
   EXPECT_TRUE(precache_delegate_.was_on_done_called());
 }
 
 #endif  // PRECACHE_MANIFEST_URL_PREFIX
 
 }  // namespace
 
 }  // namespace precache