Add daily quota for precache

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 <stdint.h>
 
 #include <cstring>
 #include <memory>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
+#include "base/rand_util.h"

[sclittle, 2016/09/14 17:59:17]

It's generally a bad idea to use any randomness in tests, since usually you can
just use a specific constant. Could you remove this dependency?

[Raj, 2016/09/14 20:01:51]

Done.

 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/stringprintf.h"
 #include "base/test/histogram_tester.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "components/precache/core/precache_database.h"
 #include "components/precache/core/precache_switches.h"
 #include "components/precache/core/proto/precache.pb.h"
 #include "components/precache/core/proto/unfinished_work.pb.h"
 #include "net/base/escape.h"
@@ skipping 1248 matching lines @@
     PrecacheFetcher precache_fetcher(
         request_context_.get(), GURL(), std::string(),
         std::move(unfinished_work), kExperimentID,
         precache_database_.GetWeakPtr(), task_runner(), &precache_delegate_);
     precache_fetcher.Start();
 
     base::RunLoop().RunUntilIdle();
   }
 }
 
+TEST_F(PrecacheFetcherTest, DailyQuota) {
+  SetDefaultFlags();
+
+  std::unique_ptr<PrecacheUnfinishedWork> unfinished_work(
+      new PrecacheUnfinishedWork());
+  unfinished_work->set_start_time(base::Time::UnixEpoch().ToInternalValue());
+  unfinished_work->add_top_host()->set_hostname("top-host-1.com");
+  unfinished_work->add_top_host()->set_hostname("top-host-2.com");
+  unfinished_work->add_top_host()->set_hostname("top-host-3.com");
+
+  PrecacheConfigurationSettings config;
+  config.set_top_sites_count(3);
+  config.set_daily_quota_total(10000000);

[sclittle, 2016/09/14 17:59:15]

Could you reduce this by a couple orders of magnitude? Like, maybe 10000?

[Raj, 2016/09/14 20:01:51]

Done.

+
+  PrecacheManifest good_manifest;

[sclittle, 2016/09/14 17:59:16]

nit: Is there some significance that this is a "good" manifest? Or could you
rename this to just "manifest"?

[Raj, 2016/09/14 20:01:51]

Done.

+  good_manifest.add_resource()->set_url(kGoodResourceURL);
+  std::string resource_data = base::RandBytesAsString(5000000);

[sclittle, 2016/09/14 17:59:16]

Don't use randomness here, could you use something like std::string(5000, 'a')?

[Raj, 2016/09/14 20:01:51]

Done.

+
+  factory_.SetFakeResponse(GURL(kConfigURL), config.SerializeAsString(),
+                           net::HTTP_OK, net::URLRequestStatus::SUCCESS);
+  factory_.SetFakeResponse(
+      GURL(std::string(kManifestURLPrefix) + "top-host-1.com"),
+      good_manifest.SerializeAsString(), net::HTTP_OK,
+      net::URLRequestStatus::SUCCESS);
+  factory_.SetFakeResponse(GURL(kGoodResourceURL), resource_data, net::HTTP_OK,
+                           net::URLRequestStatus::SUCCESS);
+  factory_.SetFakeResponse(
+      GURL(std::string(kManifestURLPrefix) + "top-host-2.com"),
+      good_manifest.SerializeAsString(), net::HTTP_OK,
+      net::URLRequestStatus::SUCCESS);
+  factory_.SetFakeResponse(GURL(kGoodResourceURL), resource_data, net::HTTP_OK,

[sclittle, 2016/09/14 17:59:16]

Why are you requesting the same resource multiple times, e.g. kGoodResourceURL?

Should these be different URLs each time? I'm worried that if someone makes a
change to e.g. eliminate duplicate fetches of the same resource while
precaching, then this test will just break.

[Raj, 2016/09/14 20:01:51]

Done.

+                           net::URLRequestStatus::SUCCESS);
+  factory_.SetFakeResponse(
+      GURL(std::string(kManifestURLPrefix) + "top-host-3.com"),
+      good_manifest.SerializeAsString(), net::HTTP_OK,
+      net::URLRequestStatus::SUCCESS);
+  factory_.SetFakeResponse(GURL(kGoodResourceURL), resource_data, net::HTTP_OK,
+                           net::URLRequestStatus::SUCCESS);
+
+  base::HistogramTester histogram;
+
+  {
+    PrecacheFetcher precache_fetcher(
+        request_context_.get(), GURL(), std::string(),
+        std::move(unfinished_work), kExperimentID,
+        precache_database_.GetWeakPtr(), task_runner(), &precache_delegate_);
+    precache_fetcher.Start();
+
+    base::RunLoop().RunUntilIdle();
+
+    EXPECT_EQ(0U, precache_fetcher.quota_.remaining());
+    unfinished_work = precache_fetcher.CancelPrecaching();
+  }
+
+  std::multiset<GURL> expected_requested_urls;
+  expected_requested_urls.insert(GURL(kConfigURL));
+  expected_requested_urls.insert(
+      GURL((std::string(kManifestURLPrefix) + "top-host-1.com")));
+  expected_requested_urls.insert(
+      GURL((std::string(kManifestURLPrefix) + "top-host-2.com")));
+  expected_requested_urls.insert(
+      GURL((std::string(kManifestURLPrefix) + "top-host-3.com")));
+  expected_requested_urls.insert(GURL(kGoodResourceURL));
+  expected_requested_urls.insert(GURL(kGoodResourceURL));
+  expected_requested_urls.insert(GURL(kGoodResourceURL));
+
+  EXPECT_EQ(expected_requested_urls, url_callback_.requested_urls());
+
+  EXPECT_TRUE(precache_delegate_.was_on_done_called());
+
+  histogram.ExpectTotalCount("Precache.Fetch.PercentCompleted", 1);
+  histogram.ExpectTotalCount("Precache.Fetch.ResponseBytes.Total", 1);
+  histogram.ExpectTotalCount("Precache.Fetch.TimeToComplete", 1);
+
+  // Continuing with the precache when quota limit is reached ,will not fetch
+  // any resources.
+  expected_requested_urls.clear();
+  url_callback_.clear_requested_urls();
+  {
+    PrecacheFetcher precache_fetcher(
+        request_context_.get(), GURL(), std::string(),
+        std::move(unfinished_work), kExperimentID,
+        precache_database_.GetWeakPtr(), task_runner(), &precache_delegate_);
+    precache_fetcher.Start();
+    base::RunLoop().RunUntilIdle();
+
+    EXPECT_EQ(0U, precache_fetcher.quota_.remaining());
+  }
+  EXPECT_EQ(expected_requested_urls, url_callback_.requested_urls());
+
+  EXPECT_TRUE(precache_delegate_.was_on_done_called());
+
+  histogram.ExpectTotalCount("Precache.Fetch.PercentCompleted", 2);
+  histogram.ExpectTotalCount("Precache.Fetch.ResponseBytes.Total", 2);
+  histogram.ExpectTotalCount("Precache.Fetch.TimeToComplete", 2);
+}
+
 }  // namespace precache