Programming WebRTC

Sending and Receiving Binary Data

You have now written all of the foundational logic to send and receive binary data along with a custom JSON payload of metadata for each file sent over a data channel. Let’s set up a sendFile() function that opens a data channel for each file a user wants to send.

To start with, create a function that takes two arguments, peer and payload, and a handful of variables:

function sendFile(peer, payload) {
  const { metadata, file } = payload;
  const file_channel =
    peer.connection.createDataChannel(`${metadata.kind}-${metadata.name}`);
  const chunk = 16 * 1024; // 16KiB chunks
}

The body of the function opens by destructuring metadata and file from payload. As you’ll see, that will simplify ...