Re: [Jmap] Question: Mandate core capability on each API call?

Benoît TELLIER <> Tue, 01 December 2020 06:33 UTC

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From: Benoît TELLIER <>
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Date: Tue, 01 Dec 2020 06:33:14 +0000
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Subject: Re: [Jmap] Question: Mandate core capability on each API call?
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Hi Neil,

Thanks for the answer.

It is not explicitly asked in the RFC so there is no reasons for server implementations to enforce it then.

I will likely relax the James expectations regarding this.

The explanation behind it would be that the session provides you an API endpoint compatible with the core capability, thus the redundant capability can be ignored.

Maybe we should warn in the client guide that including the core capability is advised, while waiting for the erratum?



On December 1, 2020 11:18 AM, from
Hi Benoit,

Good question! I thought we had specified this, but I can't see it in the final draft. I don't see any particular downside to making it optional, but perhaps someone else has an argument as to why it should be mandatory? Whatever we decide, it is probably worth an erratum for the benefit of future implementors.