Added display_name_claim in jwt_config which sets the user's display name upon registration

[EnneS]

Added the display_name_claim option to the JWT configuration. This option allows specifying the claim key that contains the user's display name in the JWT payload.

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[anoadragon453]

Thanks for your contribution @EnneS, and apologies for the slow review. I've gone ahead and added a unit test for the newly added option so we can ensure it doesn't break in the future.

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For the benefit of others: the JWT login method is non-standard, and as such we can change it without needing a Matrix Spec Change. Likewise JWT's allow adding any fields you like to them in addition to the specified ones.

The new display_name_claim option allows setting the name of the field inside the JWT payload which is expected to contain a display_name. This will only be checked on the first login of a user.

Everything checks out, thank you!

[col-panic]

Just did an issue on this #17807 - what a coincidence!

[EnneS]

Cheers (;

[col-panic]

Why isn't this mentioned in the release documentation?

[anoadragon453]

@col-panic I'm not sure what you mean, but when this is released in Synapse v1.118 the newsfile for this change will appear in the changelog and release notes.

Edit: perhaps the confusion is that the first release candidate for Synapse v1.117 was cut on October 8th, a day before this PR was merged. This change will be there in Synapse v1.118rc1, due on October 22nd, and in the full release a week later!

[col-panic]

@anoadragon453 oh ok, thank you very much, I just saw the commit that already went in, and assumed that it was forgotten!