Implements peer connection stats measurements in WebRTC call test.

tools/perf/metrics/webrtc_stats_unittest.py

+# 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.
+
+import unittest
+
+from metrics import webrtc_stats
+from telemetry.unittest import simple_mock
+
+
+SAMPLE_JSON = '''
+[[
+   [
+      {
+         "googFrameHeightInput":"480",
+         "googFrameWidthInput":"640",
+         "packetsLost":"-1",
+         "googRtt":"-1",
+         "packetsSent":"0",
+         "bytesSent":"0"
+      },
+      {
+         "audioInputLevel":"2048",
+         "googRtt":"-1",
+         "googCodecName":"opus",
+         "packetsSent":"4",
+         "bytesSent":"0"
+      }
+   ],
+   [
+      {
+         "googFrameHeightInput":"480",
+         "googFrameWidthInput":"640",
+         "packetsLost":"-1",
+         "googRtt":"-1",
+         "packetsSent":"8",
+         "bytesSent":"6291"
+      },
+      {
+         "audioInputLevel":"1878",
+         "googRtt":"-1",
+         "googCodecName":"opus",
+         "packetsSent":"16",
+         "bytesSent":"634"
+      }
+   ]
+],
+[
+   [
+      {
+         "googDecodeMs":"0",
+         "packetsReceived":"8",
+         "googRenderDelayMs":"10",
+         "googMaxDecodeMs":"0"
+      }
+   ],
+   [
+      {
+         "googDecodeMs":"14",
+         "packetsReceived":"1234",
+         "googRenderDelayMs":"102",
+         "googMaxDecodeMs":"150"
+      }
+   ]
+]]
+'''
+
+
+class FakeResults:
+  def __init__(self, current_page):
+    self._received_values = []
+    self._current_page = current_page
+
+  @property
+  def received_values(self):
+    return self._received_values
+
+  @property
+  def current_page(self):
+    return self._current_page
+
+  def AddValue(self, value):
+    self._received_values.append(value)
+
+
+class WebRtcStatsUnittest(unittest.TestCase):
+
+  def _RunMetricOnJson(self, json_to_return):
+    stats_metric = webrtc_stats.WebRtcStatisticsMetric()
+
+    tab = simple_mock.MockObject()
+    page = simple_mock.MockObject()
+
+    stats_metric.Start(page, tab)
+
+    tab.ExpectCall('EvaluateJavaScript',
+                   simple_mock.DONT_CARE).WillReturn(json_to_return)
+    stats_metric.Stop(page, tab)
+
+    page.url = simple_mock.MockObject()
+    results = FakeResults(page)
+    stats_metric.AddResults(tab, results)
+    return results
+
+  def testExtractsValuesAsTimeSeries(self):
+    results = self._RunMetricOnJson(SAMPLE_JSON)
+
+    self.assertTrue(results.received_values,
+                    'Expected values for googDecodeMs and others, got none.')
+
+    # TODO(phoglund): this is actually a bug; make the metric clever enough to
+    # distinguish packetsSent on audio from packetsSent on video, etc.
+    self.assertEqual(results.received_values[0].values,
+                     [0.0, 4.0, 8.0, 16.0])
+    self.assertEqual(results.received_values[1].values,
+                     [8.0, 1234.0])
+
+  def testExtractsInterestingMetricsOnly(self):
+    results = self._RunMetricOnJson(SAMPLE_JSON)
+
+    self.assertEqual(len(results.received_values), 4)
+    self.assertEqual(results.received_values[0].name,
+                     'peer_connection_0_packets_sent',
+                     'The result should be a ListOfScalarValues instance with '
+                     'a name <peer connection id>_<statistic>.')
+    self.assertEqual(results.received_values[1].name,
+                     'peer_connection_1_packets_received')
+    self.assertEqual(results.received_values[2].name,
+                     'peer_connection_1_goog_decode_ms')
+    self.assertEqual(results.received_values[3].name,
+                     'peer_connection_1_goog_max_decode_ms')
+
+  def testReturnsIfJsonIsEmpty(self):
+    results = self._RunMetricOnJson('[]')
+    self.assertFalse(results.received_values)
+