NQE: Add net log event if the metric changes substantially

net/nqe/event_creator_unittest.cc

Index: net/nqe/event_creator_unittest.cc
diff --git a/net/nqe/event_creator_unittest.cc b/net/nqe/event_creator_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..bc9acfb062316ad62e0ac5c57631603cebc92a55
--- /dev/null
+++ b/net/nqe/event_creator_unittest.cc
@@ -0,0 +1,127 @@
+// Copyright 2017 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 "net/nqe/event_creator.h"
+
+#include "base/memory/ptr_util.h"
+#include "base/time/time.h"
+#include "net/log/net_log_with_source.h"
+#include "net/log/test_net_log.h"
+#include "net/log/test_net_log_entry.h"
+#include "net/nqe/effective_connection_type.h"
+#include "net/nqe/network_quality.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace net {
+
+namespace nqe {
+
+namespace internal {
+
+namespace {
+
+// Returns the number of entries in |net_log| that have type set to
+// |NetLogEventType::NETWORK_QUALITY_CHANGED|.
+int GetNetworkQualityChangedEntriesCount(BoundTestNetLog* net_log) {
+  TestNetLogEntry::List entries;
+  net_log->GetEntries(&entries);
+
+  int count = 0;
+  for (const auto& entry : entries) {
+    if (entry.type == NetLogEventType::NETWORK_QUALITY_CHANGED)
+      ++count;
+  }
+  return count;
+}
+
+// Verify that the net log events are recorded correctly.
+TEST(NetworkQualityEstimatorEventCreatorTest, Notified) {
+  // std::unique_ptr<BoundTestNetLog>
+  // net_log(base::MakeUnique<BoundTestNetLog>());
+  BoundTestNetLog net_log;
+
+  EventCreator event_creator(net_log.bound());
+
+  NetworkQuality network_quality_100(base::TimeDelta::FromMilliseconds(100),
+                                     base::TimeDelta::FromMilliseconds(100),
+                                     100);
+
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_2G, network_quality_100);
+  EXPECT_EQ(1, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // No new entry should be created since the network quality has not changed.
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_2G, network_quality_100);
+  EXPECT_EQ(1, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should be created since effective connection type has changed.
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_100);
+  EXPECT_EQ(2, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should not be created since HTTP RTT has not changed
+  // meaningfully.
+  NetworkQuality network_quality_http_rtt_110(
+      base::TimeDelta::FromMilliseconds(110),
+      base::TimeDelta::FromMilliseconds(100), 100);
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_http_rtt_110);
+  EXPECT_EQ(2, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should be created since HTTP RTT has changed meaningfully.
+  NetworkQuality network_quality_http_rtt_300(
+      base::TimeDelta::FromMilliseconds(300),
+      base::TimeDelta::FromMilliseconds(100), 100);
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_http_rtt_300);
+  EXPECT_EQ(3, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should be created since transport RTT has changed meaningfully.
+  NetworkQuality network_quality_transport_rtt_300(
+      base::TimeDelta::FromMilliseconds(300),
+      base::TimeDelta::FromMilliseconds(300), 100);
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_transport_rtt_300);
+  EXPECT_EQ(4, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should be created since bandwidth has changed meaningfully.
+  NetworkQuality network_quality_kbps_300(
+      base::TimeDelta::FromMilliseconds(300),
+      base::TimeDelta::FromMilliseconds(300), 300);
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_kbps_300);
+  EXPECT_EQ(5, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should not be created since network quality has not changed
+  // meaningfully.
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_kbps_300);
+  EXPECT_EQ(5, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should be created since bandwidth has changed meaningfully.
+  NetworkQuality network_quality_kbps_2000(
+      base::TimeDelta::FromMilliseconds(300),
+      base::TimeDelta::FromMilliseconds(300), 2000);
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_kbps_2000);
+  EXPECT_EQ(6, GetNetworkQualityChangedEntriesCount(&net_log));
+
+  // A new entry should not be created since bandwidth has not changed by more
+  // than 20%.
+  NetworkQuality network_quality_kbps_2200(
+      base::TimeDelta::FromMilliseconds(300),
+      base::TimeDelta::FromMilliseconds(300), 2200);
+  event_creator.MaybeAddNetworkQualityChangedEventToNetLog(
+      EFFECTIVE_CONNECTION_TYPE_3G, network_quality_kbps_2200);
+  EXPECT_EQ(6, GetNetworkQualityChangedEntriesCount(&net_log));
+}
+
+}  // namespace
+
+}  // namespace internal
+
+}  // namespace nqe
+
+}  // namespace net