Since WCS build 5.2.1972 and SFU SDK build 2.0.273 it is possible to test publishing channel bandwidth from client to server. The test uses WebRTC data channels without a stream publishing.
WebRTC connection to a server is established when entering an SFU room
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await state.room.join(state.pc, null, {}); |
Then BitrateTest object becomes available
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const bitrateTest = state.room.getBitrateTest(); |
The BitrateTest.test() method launches the channel bandwidth test. The method accepts a maximum test duration in milliseconds, and returns a Promise which is resolved after the test ending. The test sends a data packets via WebRTC data channel, receives a feedbacks from the server about data received successfully, and computes the data sending bitrate value. A function called on the Promise resolution receives a latest measured bitrate value in kbps
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bitrateTest.test($("#" + bitrateTestState.durationId()).val()).then((bitrateKbps) => {
stateSelector.text("Test is finished, last measured bitrate: " + bitrateKbps + " kbps");
...
}); |
The BitrateTest object allows to listen for onStatusUpdate event, this event handler function receives a current measured bitrate value in kbps. This allows to display a progress indicator on a test page
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bitrateTest.setListener({
onStatusUpdate(bitrateKbps) {
stateSelector.text("Current bitrate: " + bitrateKbps + " kbps");
}
}); |
The full SFU Bitrate Test example function code to launch a channel bandwidth test
code
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const startBitrateTest = async function (state) {
if (state.room) {
await state.room.join(state.pc, null, {});
const stateSelector = $("#" + state.currentStateId());
stateSelector.attr("style", "display:inline-block;margin-left: 10px");
try {
const bitrateTest = state.room.getBitrateTest();
state.setBitrateController(bitrateTest);
bitrateTest.setListener({
onStatusUpdate(bitrateKbps) {
stateSelector.text("Current bitrate: " + bitrateKbps + " kbps");
}
});
bitrateTest.test($("#" + bitrateTestState.durationId()).val()).then((bitrateKbps) => {
stateSelector.text("Test is finished, last measured bitrate: " + bitrateKbps + " kbps");
state.setBitrateController(null);
onStopClick(state);
});
} catch (e) {
if (e.type === constants.SFU_ROOM_EVENT.OPERATION_FAILED) {
onOperationFailed(state, e);
} else {
console.error("Failed to start bitrate test: " + e);
setStatus(state.errInfoId(), e.name, "red");
onStopClick(state);
}
}
}
} |