User is unable to accept an invite to rejoin a room

[richvdh]

@ji-ef:matrix.org reports they are unable to join invite-only room for which they have received an invite. The request fails with

"The person who invited you already left the room, or their server is offline."

However, this does not appear to be the case.

event-creator logs:

2020-11-22 18:08:24,580 - synapse.http.client - 381 - INFO - POST-1274557- - Received response to POST http://10.103.0.2:9092/_synapse/replication/remote_join/%21xAvaEUXjMaaZjJCvmr%3Amatrix.nikel.me/%40ji-ef%3Amatrix.org/AzNFisDvFw: 404
2020-11-22 18:08:24,581 - synapse.http.server - 74 - INFO - POST-1274557 - <XForwardedForRequest at 0x7f7889189eb8 method='POST' uri='/_matrix/client/r0/join/!xAvaEUXjMaaZjJCvmr%3Amatrix.nikel.me' clientproto='HTTP/1.1' site=8095> SynapseError: 404 - Unknown room !xAvaEUXjMaaZjJCvmr:matrix.nikel.me
2020-11-22 18:08:24,582 - synapse.access.http.8095 - 331 - INFO - POST-1274557 - 2001:41d0:fe21:d200:226:18ff:fe9c:b2c9 - 8095 - {@ji-ef:matrix.org} Processed request: 0.785sec/-0.000sec (0.007sec, 0.001sec) (0.002sec/0.022sec/6) 84B 404 "POST /_matrix/client/r0/join/!xAvaEUXjMaaZjJCvmr%3Amatrix.nikel.me HTTP/1.1" "Mozilla/5.0 (X11; Linux x86_64; rv:83.0) Gecko/20100101 Firefox/83.0" [1 dbevts]

main process logs:

2020-11-22 18:08:23,836 - synapse.replication.http.membership - 82 - INFO - POST-7542229 - remote_join: @ji-ef:matrix.org into room: !xAvaEUXjMaaZjJCvmr:matrix.nikel.me
2020-11-22 18:08:23,841 - synapse.http.federation.well_known_resolver - 246 - INFO - POST-7542229- - Fetching https://matrix.nikel.me/.well-known/matrix/server
2020-11-22 18:08:23,931 - synapse.http.federation.well_known_resolver - 193 - INFO - POST-7542229- - Error parsing well-known for b'matrix.nikel.me': Non-200 response 404
2020-11-22 18:08:24,108 - synapse.http.matrixfederationclient - 204 - INFO - POST-7542229 - {GET-O-4167477} [matrix.nikel.me] Completed request: 200 OK in 0.27 secs - GET matrix://matrix.nikel.me/_matrix/federation/v1/make_join/%21xAvaEUXjMaaZjJCvmr%3Amatrix.nikel.me/%40ji-ef%3Amatrix.org?ver=1&ver=2&ver=3&ver=4&ver=5&ver=6
2020-11-22 18:08:24,319 - synapse.http.matrixfederationclient - 204 - INFO - POST-7542229 - {PUT-O-4167478} [matrix.nikel.me] Completed request: 200 OK in 0.20 secs - PUT matrix://matrix.nikel.me/_matrix/federation/v2/send_join/%21xAvaEUXjMaaZjJCvmr%3Amatrix.nikel.me/%24LXmL86UJTmtCapBclYu5U5rcqYqaaEj4XA6S928aI6w
2020-11-22 18:08:24,414 - synapse.http.client - 381 - INFO - POST-7542229- - Received response to POST http://10.103.0.2:8110/_synapse/replication/fed_send_events/dWRDWBpNZG: 200
2020-11-22 18:08:24,562 - synapse.http.client - 381 - INFO - POST-7542229- - Received response to POST http://10.103.0.2:8110/_synapse/replication/fed_send_events/ajIqzGfNuo: 200
2020-11-22 18:08:24,563 - synapse.replication.tcp.client - 236 - INFO - POST-7542229 - Waiting for repl stream 'events' to reach 1658357933
2020-11-22 18:08:24,572 - synapse.replication.tcp.client - 239 - INFO - POST-7542229 - Finished waiting for repl stream 'events' to reach 1658357933
2020-11-22 18:08:24,577 - synapse.http.server - 74 - INFO - POST-7542229 - <SynapseRequest at 0x7f17bf59ba20 method='POST' uri='/_synapse/replication/remote_join/%21xAvaEUXjMaaZjJCvmr%3Amatrix.nikel.me/%40ji-ef%3Amatrix.org/AzNFisDvFw' clientproto='HTTP/1.1' site=9092> SynapseError: 404 - Unknown room !xAvaEUXjMaaZjJCvmr:matrix.nikel.me
2020-11-22 18:08:24,578 - synapse.access.http.9092 - 331 - INFO - POST-7542229 - ::ffff:10.103.0.2 - 9092 - {@ji-ef:matrix.org} Processed request: 0.743sec/-0.000sec (0.049sec, 0.002sec) (0.007sec/0.034sec/6) 84B 404 "POST /_synapse/replication/remote_join/%21xAvaEUXjMaaZjJCvmr%3Amatrix.nikel.me/%40ji-ef%3Amatrix.org/AzNFisDvFw HTTP/1.1" "Synapse/1.22.1 (b=matrix-org-hotfixes,52984e9e6)" [0 dbevts]

It looks like the main process is complaining that it can't find a create event in current_state_events for that room, and indeed current_state_events contains no entries for that room at all. I've not looked for reasons this might happen (though I suspect it's getting confused by the previous state in that room)

[clokep]

I think this is a duplicate of #8596. The error message is the same and I believe the steps to reproduce are similar. (Namely be in a room, leave the room, then get invited again.)

[richvdh]

yes, sounds very similar.