Sentry: User count incorrect after merging events

[dmnd]

After I manually merge events, the user count doesn't update. For example, these two screenshots are from the same event:

This is annoying because the user count is a good way to prioritize getting errors fixed.

[dmnd]

This bug breaks one of the big attractions of using Sentry's UI — rich error-specific information. Others on my team want to stop using Sentry to manage issues and just have them piped into Jira. Quick access to the users count from the dashboard is a reason to stick with Sentry's UI, but it's hard to make that argument when it's buggy.

[dmnd]

It looks like user_count is just missing from the merge task: https://github.com/getsentry/sentry/blob/master/src/sentry/tasks/merge.py#L70

[mattrobenolt]

@dmnd It's not user_count persay, that value is derived from GroupTagKey. GroupTagKey is getting reassigned to the right group_id, but it doesn't merge the values_seen on it.

Should be a relatively easy fix.

[dmnd]

Thanks @mattrobenolt! <3

[mattrobenolt]

Turns out, the patch for this was bad and had to be reverted. Gonna try this again.

See: https://github.com/getsentry/sentry/commit/ef9986a9563a6cc44f9a7c3aca15cc3e67dfb404