Home | History | Annotate | Download | only in media
      1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #ifndef CONTENT_RENDERER_MEDIA_WEBRTC_UMA_HISTOGRAMS_H_
      6 #define CONTENT_RENDERER_MEDIA_WEBRTC_UMA_HISTOGRAMS_H_
      7 
      8 #include "base/memory/singleton.h"
      9 #include "base/threading/non_thread_safe.h"
     10 #include "content/common/content_export.h"
     11 #include "content/public/common/media_stream_request.h"
     12 
     13 namespace content {
     14 
     15 // Used to investigate where UserMediaRequests end up.
     16 // Only UserMediaRequests that do not log with LogUserMediaRequestResult
     17 // should call LogUserMediaRequestWithNoResult.
     18 //
     19 // Elements in this enum should not be deleted or rearranged; the only
     20 // permitted operation is to add new elements before
     21 // NUM_MEDIA_STREAM_REQUEST_WITH_NO_RESULT.
     22 enum MediaStreamRequestState {
     23   MEDIA_STREAM_REQUEST_EXPLICITLY_CANCELLED = 0,
     24   MEDIA_STREAM_REQUEST_NOT_GENERATED = 1,
     25   MEDIA_STREAM_REQUEST_PENDING_MEDIA_TRACKS = 2,
     26   NUM_MEDIA_STREAM_REQUEST_WITH_NO_RESULT
     27 };
     28 
     29 void LogUserMediaRequestWithNoResult(MediaStreamRequestState state);
     30 void LogUserMediaRequestResult(MediaStreamRequestResult result);
     31 
     32 // Helper enum used for histogramming calls to WebRTC APIs from JavaScript.
     33 enum JavaScriptAPIName {
     34   WEBKIT_GET_USER_MEDIA,
     35   WEBKIT_PEER_CONNECTION,
     36   WEBKIT_DEPRECATED_PEER_CONNECTION,
     37   WEBKIT_RTC_PEER_CONNECTION,
     38   WEBKIT_GET_MEDIA_DEVICES,
     39   INVALID_NAME
     40 };
     41 
     42 // Helper method used to collect information about the number of times
     43 // different WebRTC APIs are called from JavaScript.
     44 //
     45 // This contributes to two histograms; the former is a raw count of
     46 // the number of times the APIs are called, and be viewed at
     47 // chrome://histograms/WebRTC.webkitApiCount.
     48 //
     49 // The latter is a count of the number of times the APIs are called
     50 // that gets incremented only once per "session" as established by the
     51 // PerSessionWebRTCAPIMetrics singleton below. It can be viewed at
     52 // chrome://histograms/WebRTC.webkitApiCountPerSession.
     53 void UpdateWebRTCMethodCount(JavaScriptAPIName api_name);
     54 
     55 // A singleton that keeps track of the number of MediaStreams being
     56 // sent over PeerConnections. It uses the transition to zero such
     57 // streams to demarcate the start of a new "session". Note that this
     58 // is a rough approximation of sessions, as you could conceivably have
     59 // multiple tabs using this renderer process, and each of them using
     60 // PeerConnections.
     61 //
     62 // The UpdateWebRTCMethodCount function above uses this class to log a
     63 // metric at most once per session.
     64 class CONTENT_EXPORT PerSessionWebRTCAPIMetrics : public base::NonThreadSafe {
     65  public:
     66   virtual ~PerSessionWebRTCAPIMetrics();
     67 
     68   static PerSessionWebRTCAPIMetrics* GetInstance();
     69 
     70   // Increment/decrement the number of streams being sent or received
     71   // over any current PeerConnection.
     72   void IncrementStreamCounter();
     73   void DecrementStreamCounter();
     74 
     75  protected:
     76   friend struct DefaultSingletonTraits<PerSessionWebRTCAPIMetrics>;
     77   friend void UpdateWebRTCMethodCount(JavaScriptAPIName);
     78 
     79   // Protected so that unit tests can test without this being a
     80   // singleton.
     81   PerSessionWebRTCAPIMetrics();
     82 
     83   // Overridable by unit tests.
     84   virtual void LogUsage(JavaScriptAPIName api_name);
     85 
     86   // Called by UpdateWebRTCMethodCount above. Protected rather than
     87   // private so that unit tests can call it.
     88   void LogUsageOnlyOnce(JavaScriptAPIName api_name);
     89 
     90  private:
     91   void ResetUsage();
     92 
     93   int num_streams_;
     94   bool has_used_api_[INVALID_NAME];
     95 
     96   DISALLOW_COPY_AND_ASSIGN(PerSessionWebRTCAPIMetrics);
     97 };
     98 
     99 } //  namespace content
    100 
    101 #endif  // CONTENT_RENDERER_MEDIA_WEBRTC_UMA_HISTOGRAMS_H_
    102