Re: [whatwg/fetch] Trailer support in the API (#981)

Keep in mind that these are reversed on client and server sides. 

On the client side, a `trailers` callback would need to be provided in the `RequestInit`, while on the server-side, it needs to be on the `ResponseInit`.

On the receiving side, setting up an "on trailers" callback would avoid the issue of ordering when consuming the body.

```
// client side fetch api
const resp = await fetch('http://example.org', {
  headers: { 'trailers': 'foo' },
  // Called when sending the headers...
  trailers(headers) {
    headers.set('foo', 'bar');
  }
}

resp.ontrailers = (headers) => {
  // Called when trailers are received.
};
```

```
// server side fetch api
export default {
  async fetch(req) {
    req.ontrailers = (headers) => {
     // Called when trailers are received
    };
    // ...
   return new Response(stream, {
    headers: { 'trailers': 'foo' },
    trailers(headers) {
      headers.set('foo', 'bar');
    }
   });
  }
}
```


-- 
Reply to this email directly or view it on GitHub:
https://github.com/whatwg/fetch/issues/981#issuecomment-1642732284
You are receiving this because you are subscribed to this thread.

Message ID: <whatwg/fetch/issues/981/1642732284@github.com>