Programming WebRTC

Adding a Text-Chat Feature

Let’s add a more useful feature to the app: a text chat. Anyone who’s ever shared a URL in a text chat on a video call already knows how useful text chats can be, independent of full audio and video capabilities. A text chat also makes a call more accessible to users who cannot speak or hear, or be heard, for any reason.

By building a text chat, we’re going to learn how to work with negotiated data channels. As you read in the last section, the method for adding negotiated channels to a call differs somewhat from the asymmetric data channels we used for the video filters. We’ll also learn how to send data over data channels, which works the same way on symmetric and asymmetric data channels. And to make for a more ...