WebRTC Statistics API - Web APIs 编辑

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The WebRTC API has a vast array of statistics available, covering the entire breadth of the WebRTC connectivity system, from sender to receiver and peer to peer.

Collecting statistics

You can collect statistics at various levels throughout the WebRTC hierarchy of objects. Most broadly, you can call getStats() on an RTCPeerConnection to get statistics for the connection overall. In this example, a new RTCPeerConnection is created, and then setInterval() is used to set the function getConnectionStats() to be called every second.

That function, in turn, uses getStats() to obtain statistics for the connection and to make use of that data.

try {
  myPeerConnection = new RTCPeerConnection(pcOptions);

  statsInterval = window.setInterval(getConnectionStats, 1000);
  /* add event handlers, etc */
} catch(err) {
  console.error("Error creating RTCPeerConnection: " + err);
}

function getConnectionStats() {
  myPeerConnection.getStats(null).then(stats => {
    var statsOutput = "";

    stats.forEach(report => {
      if (report.type === "inbound-rtp" && report.kind === "video") {
        Object.keys(report).forEach(statName => {
          statsOutput += `<strong>${statName}:</strong> ${report[statName]}<br>\n`;
        });
      }
    });

    document.querySelector(".stats-box").innerHTML = statsOutput;
  });
}

When the promise returned by getStats() is fulfilled, the resolution handler receives as input an RTCStatsReport object containing the statistics information. This object contains a Map of named dictionaries based on RTCStats and its affiliated types.

This example specifically looks for the report whose type is inbound-rtp and whose kind is video. This way, we look only at the video-related statistics for the local RTCRtpReceiver responsible for receiving the streamed media.

Commonly used statistics

Reference

The RTCStatsReport object contains a map of named objects based one of the RTCStats dictionary's subclasses. Upon looking up a statistic category by name, you get an object containing the corresponding data. The table below shows the statistic categories and the corresponding dictionaries; for each statistic category, the full hierarchy of RTCStats-based dictionaries are listed, so you can easily find all the available values.

Specifications