Delete Account

When creating/editing a user, we have the option to disable changing the email address without taking away any other permissions. However, I don't see an option to prevent account deletion by the user. Is this by design?

Going thru the code, I noticed if registration is not enabled on the server, it will not allow deleting accounts. Is that how it's supposed to be controlled?

Yes.

something similar to this
when i create a user and i delete its account using the same user account the server stops working and i get this error:

Cannot invoke "org.traccar.model.User.check Disabled()" because the return value of "org.traccar.api.security.PermissionsService.getUser(long)" is null - NullPointerException (SecurityRequestFilter:104 < ... < OverrideFilter:50 < ...)

the only possible solution for the service to resume working is to restart traccar
here is the log

2023-08-26 16:24:35  INFO: [T7bc601b2: freedom < 5.104.80.149] 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
2023-08-26 16:24:49  INFO: [T26365962] timed out
2023-08-26 16:24:49  INFO: [T26365962] disconnected
2023-08-26 16:25:05  INFO: [T7bc601b2] timed out
2023-08-26 16:25:05  INFO: [T7bc601b2] disconnected
2023-08-26 16:27:07  INFO: [T317d84f6] connected
2023-08-26 16:27:07  INFO: [T317d84f6: startek < 184.105.139.69] 3c3f786d6c2076657273696f6e3d27312e30273f3e3c73747265616d3a73747265616d20786d6c6e733a73747265616d3d27687474703a2f2f6574686572782e6a61626265722e6f72672f73747265616d732720786d6c6e733d276a61626265723a636c69656e742720786d6c3a6c616e673d27656e2d55532720746f3d272e272076657273696f6e3d27312e30273e
2023-08-26 16:27:11  INFO: [T317d84f6] disconnected
2023-08-26 16:27:53  INFO: user: 4, action: remove, object: user, id: 4
2023-08-26 16:27:58  INFO: [Ta865a03d] connected
2023-08-26 16:27:58  INFO: [Ta865a03d: freedom < 78.128.114.2] 0300002f2ae00000000000436f6f6b69653a206d737473686173683d41646d696e697374720d0a0100080003000000
2023-08-26 16:28:28  INFO: [Ta865a03d] timed out
2023-08-26 16:28:28  INFO: [Ta865a03d] disconnected
2023-08-26 16:29:51  INFO: [Ted07fa0f] connected
2023-08-26 16:29:51  INFO: [Ted07fa0f: teltonika < 78.128.114.2] 0300002f2ae00000000000436f6f6b69653a206d737473686173683d41646d696e697374720d0a0100080003000000
2023-08-26 16:30:03  INFO: [T9975a5cf] connected
2023-08-26 16:30:03  INFO: [T9975a5cf: navis < 78.128.114.2] 0300002f2ae00000000000436f6f6b69653a206d737473686173683d41646d696e697374720d0a0100080003000000
2023-08-26 16:30:21  INFO: [Ted07fa0f] timed out
2023-08-26 16:30:21  INFO: [Ted07fa0f] disconnected
2023-08-26 16:30:33  INFO: [T9975a5cf] timed out
2023-08-26 16:30:33  INFO: [T9975a5cf] disconnected

1. What exactly stops working?
2. Is this reproducible on a clean server with the latest version of Traccar?

im using traccar version 5.8 windows version and also the same behaviors happen in my vps Linux setup
ps: i did some customization on web modern interface.
1-the traccar service stops working as soon as the user click delete user
2-yes it isreproducible on a clean server with the latest version , all you need to do is register your admin, log out, register another user example test, log in to test, delete test account , you ll be send to the log in page and if you refresh you ll find the server isnt working now,

suggestion: i suggest to you if i may to change to email field to password field in order for a user to delete his account

OK, I was able to reproduce the issue, but server was not crashing. It's just session was not cleared. You could either clear browser cache or login from a different device just fine. Fixed now.