Update sse.rs: add space between duration and :

[GlenDC]

Motivation

retry was the only field for which we did not add a space

Solution

[jplatte]

Thanks for the PR! Pinging @SabrinaJewson for review since I still have close to no knowledge of SSE.

[SabrinaJewson]

Seems reasonable either way to me. FWIW, Spaces are mandatory for all the other fields because the field value itself may start with a space (including json in case the user uses RawValue for example), and retry is the only field where it’s not necessary. But having consistency also makes sense.

[GlenDC]

Seems reasonable either way to me. FWIW, Spaces are mandatory for all the other fields because the field value itself may start with a space (including json in case the user uses RawValue for example), and retry is the only field where it’s not necessary. But having consistency also makes sense.

strictly speaking, https://html.spec.whatwg.org/multipage/server-sent-events.html, defines spaces as always optional. If the first character of the value is a space it is to be removed, regardless of the field.

That said any other field in Axum's SSE implementation uses a space so there's little reason not to do it for retry. On top of that all other implementations I am aware of use a space, and some test suites rely on this space to be there.

Therefore I would argue to just add a space here as well. It doesn't hurt, it makes it more consistent, aligns with other implementations and doesn't do harm anywhere.

[jplatte]

I wonder whether this should have a changelog entry 🤔

[GlenDC]

I wonder whether this should have a changelog entry 🤔

are you planning to do a release soon? how often are these releases? Otherwise I might, if you are ok with it, want to still squeeze in the original issue I posted (about exposing the writer)

[jplatte]

No immediate plans for a release, no. Feel free to include the changelog entry in your next PR. Thanks!