payload for 300 responses

[julian.reschke@…]

Ted Lemon:

I'm left entirely unclear as to what a 300 response would look like based in the text in 3.4.2 and 6.4.1. Am I missing something?

...

So as an editorial comment, which you may freely ignore, if in fact there exist no automatic mechanisms for doing this, it would help to say that the normal current practice is to simply present a web page and offer the user a choice, but that it is entirely possible that automated mechanisms will be defined in the future.

[julian.reschke@…]

The spec currently says:

For request methods other than HEAD, the server SHOULD generate a payload in the 300 response containing a list of representation metadata and URI reference(s) from which the user or user agent can choose the one most preferred. The user agent MAY make a selection from that list automatically, depending upon the list format, but this specification does not define a standard for such automatic selection.

Should we clarify that currently there is no widely used format for automatic selection?

[fielding@…]

I tried to define a standard response format in April 1995 (​Danvers IETF 32, HTTP minutes) and was prevented by the WG because HTTP is supposed to be orthogonal to the media types used as payload. Hence, any format can be used.

[fielding@…]

From [2562]:

(editorial) explain why 300 does not have a defined format and describe how it is typically implemented in practice; addresses #548