Handle unsupported content types

As more custom and standards-track content types are introduced into the XMTP ecosystem, your app may encounter content types it does not support. This situation, if not handled properly, could lead to app crashes.

Each message is accompanied by a fallback property, which offers a descriptive string representing the content type's expected value. It's important to note that fallbacks are immutable and are predefined in the content type specification. In instances where fallback is undefined, such as read receipts, it indicates that the content is not intended to be rendered. If you're venturing into creating custom content types, you're provided with the flexibility to specify a custom fallback string. For a deeper dive into this, see Build custom content types.

const codec = client.codecFor(content.contentType);
if (!codec) {
  /*Not supported content type*/
  if (message.fallback !== undefined) {
    return message.fallback;
  }
  // Handle other types like ReadReceipts which are not meant to be displayed
}