How can you use WebRTC to video chat on a website?

3 How to set up a WebRTC video chat app?

To create a WebRTC video chat app, you need to get the user's permission to access their media devices using the MediaStream API. Then, create a local media stream and display it in a video element using the URL.createObjectURL method. Additionally, you must set up a signaling server that can relay messages between the participants, such as offer, answer, and candidate. You can use any server-side technology, such as Node.js, PHP, or Python, to implement the signaling logic. After that, create a peer connection object using the RTCPeerConnection API and add the local media stream to it with the addStream method. To initiate the connection, generate an offer with the createOffer method and send it to the other participant via the signaling server. When you receive an answer from them via the signaling server, set it as the remote description using the setRemoteDescription method. Then exchange ICE candidates between both participants using the onicecandidate and addIceCandidate methods to find the best network path for the connection. Finally, receive and display the remote media stream from the other participant in another video element using the URL.createObjectURL method.

4 How to use RTCDataChannel to send and receive data?

In addition to media streams, you can also use WebRTC to send and receive any type of data using the RTCDataChannel API. To do so, you must first create a data channel object using the createDataChannel method on the peer connection object, specifying a label and some options such as ordered, reliable, or binaryType. Additionally, you need to add an onmessage event handler to the data channel object to receive data from the other participant, an onopen event handler to check when the channel is ready to send data, and an onclose event handler to check when it is closed. Then, you can use the send method on the data channel object to send data to the other participant - strings, blobs, or array buffers depending on the binaryType option.

5 How to handle errors and events in WebRTC?

WebRTC is a complex and dynamic technology that can encounter various errors and events during video chat sessions. To handle these, you need to add an onerror event handler to the peer connection object, the data channel object, and the media stream object to catch any errors that may occur. Additionally, an oniceconnectionstatechange event handler should be added to monitor the state of the ICE connection, while an onsignalingstatechange event handler should be added to monitor the state of the signaling process. To receive media tracks from the other participant, an ontrack event handler should be used in place of the onaddstream and addStream methods. Lastly, an onnegotiationneeded event handler should be added to trigger a new offer/answer exchange when the configuration of the peer connection changes.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?