Crash after first execution of retrieving mails or infinite loop

[HighIander]

The plugin connects correctly to my imap, pulls the messages, puts them in the correct thread but then often crashes:

{"level":"info","ts":1613511169.067622,"caller":"bleveengine/bleve.go:267","msg":"UpdateConf Bleve"}
{"level":"error","ts":1613511337.1845307,"caller":"plugin/health_check.go:59","msg":"Health check failed for plugin","id":"com.mattermost.mailermost-plugin","error":"Plugin RPC connection is not responding"}
{"level":"warn","ts":1613511337.1847084,"caller":"plugin/hclog_adapter.go:69","msg":"error closing client during Kill","plugin_id":"com.mattermost.mailermost-plugin","wrapped_extras":"errconnection is shut down"}
{"level":"warn","ts":1613511337.184723,"caller":"plugin/hclog_adapter.go:71","msg":"plugin failed to exit gracefully","plugin_id":"com.mattermost.mailermost-plugin"}

Once I restart, it pulls the same messages from imap again, creating duplicates, and then crashes again.

If it doesn't crash, it still pulls the same messages over and over again. On the server, the deleted flag is set, but the plugin never checks if the flag is set before adding it to mattermost. I think the expected behaviour would be that the mesages actually get deleted. I believe that this only happens once the client is actively closed - which seems to never happen. after the messages are processed.

[hanzei]

@HighIander Could you please set the log level to debug and check if you see any messages before "Health check failed for plugin"?

[HighIander]

@hanzei thanks for asking! However, the logging level was already set to debug, hence there is no more information in the log, unfortunately.
However, the crash does not occur anymore after I deleted all mail, one of which was a mail that was not a reply to mattermost but a regular mail. I saw that the crash happened right after processing the mails before this one, the others after were not processed. So I figured it might due to this one mail.
Anyhow, the problem of continuous duplicates persists. I'm not sure if it is related, but if the mailbox is empty, the plugin writes an error to the log everytime it checks - to it sounds more like a debug info, should not be an error, right?
{"level":"error","ts":1613592847.2243123,"caller":"mlog/sugar.go:23","msg":"Failed to poll mailbox","plugin_id":"com.mattermost.mailermost-plugin","error":"No matching messages"}

[pat-s]

I also saw this. Cleared all messages and now it seems to work again.