Sending the time of the pingback request in the request

components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.cc

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.cc
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.cc
index 00cca9f3bbd6524dc214107acc00b772a5405eb4..13942ad271dc5387facf02eb27634359926db3a2 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.cc
@@ -1,19 +1,20 @@
 // Copyright 2016 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/data_reduction_proxy/core/browser/data_reduction_proxy_pingback_client.h"
 
 #include "base/metrics/histogram.h"
 #include "base/optional.h"
 #include "base/rand_util.h"
+#include "base/time/time.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_data.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_page_load_timing.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_util.h"
 #include "components/data_reduction_proxy/proto/client_config.pb.h"
 #include "components/data_reduction_proxy/proto/pageload_metrics.pb.h"
 #include "net/base/load_flags.h"
 #include "net/url_request/url_fetcher.h"
 #include "net/url_request/url_request_context_getter.h"
 #include "net/url_request/url_request_status.h"
@@ -21,26 +22,29 @@
 
 namespace data_reduction_proxy {
 
 namespace {
 
 static const char kHistogramSucceeded[] =
     "DataReductionProxy.Pingback.Succeeded";
 static const char kHistogramAttempted[] =
     "DataReductionProxy.Pingback.Attempted";
 
-// Creates a PageloadMetrics protobuf for this page load and serializes to a
-// string.
-std::string SerializeData(const DataReductionProxyData& request_data,
-                          const DataReductionProxyPageLoadTiming& timing) {
-  RecordPageloadMetricsRequest batched_request;
-  PageloadMetrics* request = batched_request.add_pageloads();
+// Creates a RecordPageloadMetrics protobuf for this page load based on page
+// timing and data reduction proxy state.
+std::unique_ptr<RecordPageloadMetricsRequest>
+CreateRecordPageloadMetricsRequest(
+    const DataReductionProxyData& request_data,
+    const DataReductionProxyPageLoadTiming& timing) {
+  std::unique_ptr<RecordPageloadMetricsRequest> batched_request(
+      new RecordPageloadMetricsRequest());
+  PageloadMetrics* request = batched_request->add_pageloads();
   request->set_session_key(request_data.session_key());
   // For the timing events, any of them could be zero. Fill the message as a
   // best effort.
   request->set_allocated_first_request_time(
       protobuf_parser::CreateTimestampFromTime(timing.navigation_start)
           .release());
   if (request_data.original_request_url().is_valid())
     request->set_first_request_url(request_data.original_request_url().spec());
   if (timing.first_contentful_paint) {
     request->set_allocated_time_to_first_contentful_paint(
@@ -59,22 +63,32 @@ std::string SerializeData(const DataReductionProxyData& request_data,
         protobuf_parser::CreateDurationFromTimeDelta(
             timing.response_start.value())
             .release());
   }
   if (timing.load_event_start) {
     request->set_allocated_page_load_time(
         protobuf_parser::CreateDurationFromTimeDelta(
             timing.load_event_start.value())
             .release());
   }
+  return batched_request;
+}
+
+// Adds |current_time| as the metrics sent time to |request_data|, and returns
+// the serialized request.
+std::string AddTimeAndSerializeRequest(
+    RecordPageloadMetricsRequest* request_data,
+    base::Time current_time) {
+  request_data->set_allocated_metrics_sent_time(
+      protobuf_parser::CreateTimestampFromTime(current_time).release());
   std::string serialized_request;
-  batched_request.SerializeToString(&serialized_request);
+  request_data->SerializeToString(&serialized_request);
   return serialized_request;
 }
 
 }  // namespace
 
 DataReductionProxyPingbackClient::DataReductionProxyPingbackClient(
     net::URLRequestContextGetter* url_request_context)
     : url_request_context_(url_request_context),
       pingback_url_(util::AddApiKeyToUrl(params::GetPingbackURL())),
       pingback_reporting_fraction_(0.0) {}
@@ -83,63 +97,73 @@ DataReductionProxyPingbackClient::~DataReductionProxyPingbackClient() {
   DCHECK(thread_checker_.CalledOnValidThread());
 }
 
 void DataReductionProxyPingbackClient::OnURLFetchComplete(
     const net::URLFetcher* source) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(source == current_fetcher_.get());
   UMA_HISTOGRAM_BOOLEAN(kHistogramSucceeded, source->GetStatus().is_success());
   current_fetcher_.reset();
   while (!current_fetcher_ && !data_to_send_.empty()) {
-    current_fetcher_ = MaybeCreateFetcherForDataAndStart(data_to_send_.front());
+    current_fetcher_ =
+        MaybeCreateFetcherForDataAndStart(data_to_send_.front().get());
     data_to_send_.pop_front();
   }
 }
 
 void DataReductionProxyPingbackClient::SendPingback(
     const DataReductionProxyData& request_data,
     const DataReductionProxyPageLoadTiming& timing) {
   DCHECK(thread_checker_.CalledOnValidThread());
-  std::string serialized_request = SerializeData(request_data, timing);
+  std::unique_ptr<RecordPageloadMetricsRequest>
+      record_pageload_metrics_request =
+          CreateRecordPageloadMetricsRequest(request_data, timing);
   if (current_fetcher_.get()) {
-    data_to_send_.push_back(serialized_request);
+    data_to_send_.push_back(std::move(record_pageload_metrics_request));
   } else {
     DCHECK(data_to_send_.empty());
-    current_fetcher_ = MaybeCreateFetcherForDataAndStart(serialized_request);
+    current_fetcher_ = MaybeCreateFetcherForDataAndStart(
+        record_pageload_metrics_request.get());
   }
 }
 
 std::unique_ptr<net::URLFetcher>
 DataReductionProxyPingbackClient::MaybeCreateFetcherForDataAndStart(
-    const std::string& request_data) {
+    RecordPageloadMetricsRequest* request_data) {
   bool send_pingback = ShouldSendPingback();
   UMA_HISTOGRAM_BOOLEAN(kHistogramAttempted, send_pingback);
   if (!send_pingback)
     return nullptr;
+  std::string serialized_request =
+      AddTimeAndSerializeRequest(request_data, CurrentTime());
   std::unique_ptr<net::URLFetcher> fetcher(
       net::URLFetcher::Create(pingback_url_, net::URLFetcher::POST, this));
   fetcher->SetLoadFlags(net::LOAD_BYPASS_PROXY);
-  fetcher->SetUploadData("application/x-protobuf", request_data);
+  fetcher->SetUploadData("application/x-protobuf", serialized_request);
   fetcher->SetRequestContext(url_request_context_);
   // Configure max retries to be at most kMaxRetries times for 5xx errors.
   static const int kMaxRetries = 5;
   fetcher->SetMaxRetriesOn5xx(kMaxRetries);
   fetcher->SetAutomaticallyRetryOnNetworkChanges(kMaxRetries);
   fetcher->Start();
   return fetcher;
 }
 
 bool DataReductionProxyPingbackClient::ShouldSendPingback() const {
   return params::IsForcePingbackEnabledViaFlags() ||
          GenerateRandomFloat() < pingback_reporting_fraction_;
 }
 
+base::Time DataReductionProxyPingbackClient::CurrentTime() const {
+  return base::Time::Now();
+}
+
 float DataReductionProxyPingbackClient::GenerateRandomFloat() const {
   return static_cast<float>(base::RandDouble());
 }
 
 void DataReductionProxyPingbackClient::SetPingbackReportingFraction(
     float pingback_reporting_fraction) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK_LE(0.0f, pingback_reporting_fraction);
   DCHECK_GE(1.0f, pingback_reporting_fraction);
   pingback_reporting_fraction_ = pingback_reporting_fraction;