Send sound through microphone in javascript

Question

I'm using Selenium to emulate an user on a web that has audio chat. I need to emulate the user speaking through the microphone.

I only got questions about listening to the microphone in javascript, but none about sending sound through the microphone using javascript.

My current attempt looks like this:

First I check that AudioContext is available

private boolean isAudioContextSupported() {
  JavascriptExecutor js = (JavascriptExecutor) getDriver();
  Object response = js.executeAsyncScript(
  "var callback = arguments[arguments.length - 1];" +
  "var context;" + 
  "try {" + 
  "  window.AudioContext = window.AudioContext||window.webkitAudioContext;" + 
  "  context = new AudioContext();" +
  "  callback('');" +
  "}" + 
  "catch(e) {" + 
  "  callback('Web Audio API is not supported in this browser');" + 
  "}");
  String responseAsString = response == null?"":(String)response;
  return responseAsString.isEmpty();
}

Second I try to do this to get audio from an url

JavascriptExecutor js = (JavascriptExecutor) getDriver();
Object response = js.executeAsyncScript(
  "var callback = arguments[arguments.length - 1];" +
  "window.AudioContext = window.AudioContext || window.webkitAudioContext;" + 
  "var context = new AudioContext();" +
  "var url = '<ogg file url>';" +
  "var request = new XMLHttpRequest();" +
  "request.open('GET', url, true);" + 
  "request.responseType = 'arraybuffer';" +
  "request.onload = function() {" + 
  "  context.decodeAudioData(request.response, function(buffer) {" + 
  "  <send the buffer data through the microphone>" +
  "}, callback(request.statusText));" + 
  "};" + 
  "request.send();" +
  "callback('OK');"
);

The part I'm missing is how to send the buffer data (obtained from the ogg file) through the microphone.

EDIT:

The answer in Chrome: fake microphone input for test purpose does not answer this question, I already read that one.

EDIT 2:

There are some things to be considered:

1) The solution I'm looking can include using another language or tool.

2) I can't use hardware to emulate mic input (e.g.: output sound via speakers so the microphone can pick it up)

Answer 1

I think you don't need to use JavascriptExecutor.

There is a hack for your problem.

Solution:

Use java instead.

Step 1:

Execute the chat voice listener.

Step 2:

Now play a random voice programmatically.

Use: import javazoom.jl.player.Player;

public void playAudio(String audioPath)  { 

        try {
            FileInputStream fileInputStream = new FileInputStream(audioPath);
            Player player = new Player((fileInputStream));
            player.play();
            System.out.println("Song is playing");
        }catch (Exception ex)  { 
            System.out.println("Error with playing sound."); 
            ex.printStackTrace(); 

        } 
    } 

Step 3:

To enable microphone access, kindly use the below argument:

options.addArguments("use-fake-ui-for-media-stream"); 

Above code will play the sound for you and your chat listener can listen the played audio.

Answer 2

I don't know much about running Selenium with Java. But it looks like you can execute arbitrary JavaScript code before running the tests. I guess your code does at some point call getUserMedia() to get the microphone input. Therefore it might work if you just replace that function with a function that returns a MediaStream of your audio file.

navigator.mediaDevices.getUserMedia = () => {
    const audioContext = new AudioContext();

    return fetch('/your/audio/file.ogg')
        .then((response) => response.arrayBuffer())
        .then((arrayBuffer) => audioContext.decodeAudioData(arrayBuffer))
        .then((audioBuffer) => {
            const audioBufferSourceNode = audioContext.createBufferSource();
            const mediaStreamAudioDestinationNode = audioContext.createMediaStreamDestination();

            audioBufferSourceNode.buffer = audioBuffer;
            // Maybe it makes sense to loop the buffer.
            audioBufferSourceNode.loop = true;

            audioBufferSourceNode.start();

            audioBufferSourceNode.connect(mediaStreamAudioDestinationNode);

            return mediaStreamAudioDestinationNode.stream;
        });
};

Maybe you also have to disable the autoplay policy in order to make it work.

Unfortunately the code for Safari needs to be a bit more complicated because decodeAudioData() doesn't return a promise in Safari. I did not add the workaround here to keep the code as simple as possible.