Section 6 on C2S does not describe side effects of Accept or Reject

[trwnh]

This came up in issue triage a few weeks ago but we seem to have forgotten to capture it? (I can't find a related issue, at least.)

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S2S Accept describes receiving an Accept Follow in your inbox, which should add the actor to your following collection. But there is no language in C2S that describes Accept, or specifically that sending an Accept Follow should add that inner actor to your followers collection.

Likewise, S2S Reject describes how receiving a Reject Follow in your inbox MUST NOT result in adding that actor to your following collection, but there is no language in C2S that describes Reject, or specifically that sending a Reject Follow MUST NOT add that inner actor to your followers collection.

[evanp]

Yes, I think it was an oversight to leave out Accept and Reject from the API section of the specification. IIRC, we originally expected that Follow would be a single activity, not requiring acceptance or rejection, and then added it due to implementation feedback. Since many implementers were using the protocol but not the API, I think we just added it to the server-to-server section.

I think if we are open to adding longer errata, it would make sense to add two subsections for Accept and Reject in section 6. If not, we should plan to expand this in the next version of ActivityPub.

[evanp]

We have primer pages about Accept and Reject here:

• https://www.w3.org/wiki/ActivityPub/Primer/Accept_activity
• https://www.w3.org/wiki/ActivityPub/Primer/Reject_activity