Offline sender can't recover from crashes

[alahiff]

This is using: 2.0.0a2

Not sure what's going on here:

Fri Feb 28 04:28:01 GMT 2025
INFO:simvue.bin.sender:Starting Simvue Sender
CRITICAL:simvue.bin.sender:Exception running sender: Expecting value: line 1 column 1 (char 0)

After this it never ran successfully again:

INFO:simvue.bin.sender:Starting Simvue Sender
CRITICAL:simvue.bin.sender:Exception running sender: A sender is already running for this cache!

and all runs were lost.

I'll try running it again but remove the try...except... in order to get more information about the error (assuming it happens again).

[wk9874]

Damn, not sure what the original crash is for, but the reason itll never try again is because of the locking I added. Maybe the entirety of sender should be in a try except and it always removes the lock file before raising the exception

[wk9874]

(also have you still got the offline cache stored from the time when the sender failed until now? If so we can probably recover it, just need to find what is causing the sender to fail and then manually remove the lock file)

[alahiff]

I've already deleted it and started some new runs.

One option could be to store the pid of the sender process in the lock file. Then if a lock file exists the sender could check if the process is running. If it's not, then it could replace the lock file and start running.

[wk9874]

I'm going to split this out into two issues - the sender being locked permanently if it crashed, and one to investigate why it crashed in the first place...

See #738