HTTP 103 Early Hints

[ronag]

https://evertpot.com/http/103-early-hints

Request from: #179

Related topic; how would HTTP 103 Early Hints play out? It would be very nice to have a way to get the early hints data in a way before the header and body.

I have a real use case for 103.

@trygve-lie

[ronag]

I'm unsure if https://www.npmjs.com/package/http-parser-js supports this.

[ronag]

Does Node core supports this? @mcollina do you know?

[mcollina]

I think Node.js core support this.

[trygve-lie]

Yeah. Node.js core supports it: nodejs/node#16644

[ronag]

@mcollina @szmarczak @delvedor I don't really see an elegant way forward given the current API to support 1xx informational responses... I am little concerned about this. Would like to try to avoid future significant breaking API changes.

Maybe in the client.stream API we could invoke the handler multiple times and when the body is nully then it should be interpreted as informational response? This approach kind of could work with client.pipeline as well but would be a bit weird. This would however need to be documented (might as well add it). However, I have no good ideas for client.request maybe return an async generator?

100 Continue - Probably no big deal if we don't support.
101 Switching Protocols - Should make it at least possible for the user to perform the switch.
102 Processing (WebDAV; RFC 2518) - Probably no big deal if we don't support.
103 Early Hints (RFC 8297) - Not sure... would be nice

Ideas?

[ronag]

If we don't support 101 should we throw on method CONNECT?

[mcollina]

Throw on 101.

I'm happy with the rest.

[ronag]

I'm happy with the rest.

I assume you mean that you are happy with the status quo? i.e. no 103 support.

[mcollina]

I'm happy to cut a release with no 103 early hints.

@trygve-lie what's your use case?