Should POLL URL be specified in the "delivery methods supported"?

[FragLegs]

From @atultulshi in a comment on #9

In the Transmitter Configuration Metadata, should we modify the "delivery methods supported" to include the POLL URL if the method is POLL?

[timcappalli]

call 2023-03-21: is there any case where the poll URI is unique per stream? @FragLegs / @atultulshi @tulshi

[FragLegs]

The poll URI MUST be unique per-stream, otherwise it is unclear which stream the Receiver is polling. So it would be hard to add it to the Transmitter Configuration Metadata. I'm not sure what advantage is gained by adding it there, since the Receiver already has access to it in the Stream Configuration data.

[tulshi]

In the current spec, the "delivery" field of the stream configuration is specified to be "Receiver supplied". This is OK for the push method, but for the poll method, the URL needs to be specified by the Transmitter, not the Receiver. Also, the text of the spec talks about a special field "method", but the examples give the field "delivery_method". We should clarify this in the updated spec.

[FragLegs]

Hmm, that one is tricky. The Receiver is responsible for setting the method field of the delivery object, but if the Receiver selects "poll" then the Transmitter has to fill in the url field. So it is mostly Receiver supplied, but you are right that we should call out the Transmitter's responsibility when the Receiver chooses "poll".

[tulshi]

Labeled this as a bug, because implementers cannot discover the POLL URL of a Transmitter in the current spec.