RTCStatsCollector and RTCPeerConnectionStats added.
This is the stats collector for the new stats types, RTCStats[1] and
RTCStatsReport[2]. It so far only produces RTCPeerConnectionStats[3] as
an example of how it would collect stats. Each RTCStats subclass will
get a corresponding RTCStatsCollector::ProduceFooStats().
Stats reports are cached and returned as const references (ref
counting). This allows stats to be inspected by multiple observers and
across multiple threads. No copies will have to be made when surfacing
this to Blink or other places.
The current implementation of ProducePeerConnectionStats() only look at
existing DataChannels. This might be incorret if data channels can be
removed? Will investigate in a follow-up, crbug.com/636818.
[1] https://www.w3.org/TR/2016/WD-webrtc-20160531/#idl-def-rtcstats
[2] https://www.w3.org/TR/2016/WD-webrtc-20160531/#rtcstatsreport-object
[3] https://w3c.github.io/webrtc-stats/archives/20160526/webrtc-stats.html#pcstats-dict*
BUG=chromium:627816, chromium:636818
Review-Url: https://codereview.webrtc.org/2242043002
Cr-Commit-Position: refs/heads/master@{#13979}
diff --git a/webrtc/stats/rtcstatscollector.cc b/webrtc/stats/rtcstatscollector.cc
new file mode 100644
index 0000000..6cb2a31
--- /dev/null
+++ b/webrtc/stats/rtcstatscollector.cc
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2016 The WebRTC Project Authors. All rights reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/stats/rtcstatscollector.h"
+
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include "webrtc/api/peerconnection.h"
+#include "webrtc/base/checks.h"
+
+namespace webrtc {
+
+RTCStatsCollector::RTCStatsCollector(
+ PeerConnection* pc,
+ double cache_lifetime,
+ std::unique_ptr<rtc::Timing> timing)
+ : pc_(pc),
+ timing_(std::move(timing)),
+ cache_timestamp_(0.0),
+ cache_lifetime_(cache_lifetime) {
+ RTC_DCHECK(pc_);
+ RTC_DCHECK(timing_);
+ RTC_DCHECK(IsOnSignalingThread());
+ RTC_DCHECK_GE(cache_lifetime_, 0.0);
+}
+
+rtc::scoped_refptr<const RTCStatsReport> RTCStatsCollector::GetStatsReport() {
+ RTC_DCHECK(IsOnSignalingThread());
+ double now = timing_->TimerNow();
+ if (cached_report_ && now - cache_timestamp_ <= cache_lifetime_)
+ return cached_report_;
+ cache_timestamp_ = now;
+
+ rtc::scoped_refptr<RTCStatsReport> report = RTCStatsReport::Create();
+ report->AddStats(ProducePeerConnectionStats());
+
+ cached_report_ = report;
+ return cached_report_;
+}
+
+void RTCStatsCollector::ClearCachedStatsReport() {
+ RTC_DCHECK(IsOnSignalingThread());
+ cached_report_ = nullptr;
+}
+
+bool RTCStatsCollector::IsOnSignalingThread() const {
+ return pc_->session()->signaling_thread()->IsCurrent();
+}
+
+std::unique_ptr<RTCPeerConnectionStats>
+RTCStatsCollector::ProducePeerConnectionStats() const {
+ // TODO(hbos): If data channels are removed from the peer connection this will
+ // yield incorrect counts. Address before closing crbug.com/636818. See
+ // https://w3c.github.io/webrtc-stats/webrtc-stats.html#pcstats-dict*.
+ uint32_t data_channels_opened = 0;
+ const std::vector<rtc::scoped_refptr<DataChannel>>& data_channels =
+ pc_->sctp_data_channels();
+ for (const rtc::scoped_refptr<DataChannel>& data_channel : data_channels) {
+ if (data_channel->state() == DataChannelInterface::kOpen)
+ ++data_channels_opened;
+ }
+ // There is always just one |RTCPeerConnectionStats| so its |id| can be a
+ // constant.
+ std::unique_ptr<RTCPeerConnectionStats> stats(
+ new RTCPeerConnectionStats("RTCPeerConnection", cache_timestamp_));
+ stats->data_channels_opened = data_channels_opened;
+ stats->data_channels_closed = static_cast<uint32_t>(data_channels.size()) -
+ data_channels_opened;
+ return stats;
+}
+
+} // namespace webrtc
