@rair/ingest-worker

A WebWorker for encoding and encryption

Usage

In a browser hosted javascript file it is a simple as creating a worker and sending it messages to start execution.

Ensure ingest-worker.js is hosted on the webserver as it will be automatically requested by the browser in the worker constructor.

The worker

The worker responds to messages of the form: {type: 'run', data: { fileData, format, aesKey? }}

• The fileData should be an ArrayBuffer or Uint8Array containg the binary file data
• The format is a string (e.g. 'mp4') containing a hint to the file source encoding
• aesKey is optional and is a standard browser CryptoKey for AES-128-CBC encryption that has the encrypt usage set.

e.g.

const aesKey = await window.crypto.subtle.generateKey(
  {
    name: "AES-CBC",
    length: 128
  },
  true,
  ["encrypt"]
);

Example

// requests the worker script and starts the worker
const worker = new Worker('ingest-worker.js')

// handler for any messages the worker triggers
const msg = e.data;
worker.onmessage = function(e) { 
  switch (msg.type) {
      case "ready":
      	// when it is ready send a message back instructing it to encode a file
      	// The fileData should be an ArrayBuffer or Uint8Array containg the binary file data
        worker.postMessage({type: "run", data: { file: fileData, format: 'mp4', aesKey }});
        break;
      case "stdout":
        console.log(msg.data);
        break;
      case "stderr":
        console.log(msg.data);
        break;
      case "done":
      	// encoding is complete!
      	// do something with msg.data
        break;
  }
};