"tail -F" sometime fail to follow new log file

[bhy]

On Linux it looks like tail -F may not reliably follow new log files. When this happens, chiadog will report "Your harvester appears to be offline", and inspecting the /proc file system shows that the tail process is still opening the old log file, eg. .chia/mainnet/log/debug.log.11.

Environment:

• OS: Ubuntu 20.04
• Python version: 3.8.5

[pieterhelsen]

Thanks for this insight!
It looks like that's definitive proof that we need to move away from using tail and Windows' Get-Content.

This seems like it could provide a cross-platform solution for LOCAL harvesters
https://stackoverflow.com/a/43547769

For remote harvesting, however, this will not work. One possible alternative is Paramiko's SFTPClient.open method, but this is slow (as per this discussion) and probably won't handle log rotations well.

[bhy]

Meanwhile I think the following tail option might help:

       --max-unchanged-stats=N
              with --follow=name, reopen a FILE which has not

              changed size after N (default 5) iterations to see if it has been unlinked or renamed (this  is  the  usual
              case of rotated log files); with inotify, this option is rarely useful

[pieterhelsen]

It would likely help, but it's still not very pythonic and does not work for cross-platform implementation.
I plan to spend some time on fixing this in the next couple of days.

[Gr33nDrag0n69]

This bug is what prevent me to use this software for production monitoring. Overall, very good job. Concerning the issue, I have a couple ideas on how it ccould be at least be dirty fixed before making better code for the long run. The simpliest drity fix for now could be:

When 'Your harvester appears to be offline! No events for the past X seconds.' is detected, the code could just try to reload log consumer first before sending warning.

[Gr33nDrag0n69]

Also, on windows, the current never work at all. (As soon as the logrotate code from chia logging module is executed, the harvester offline warning appear and the only is to kill and restart chiadog)

[ghost]

I can second this. Using chiadog in WSL for monitoring my windows plotter and farmer. My files split roughly every 22minutes and I am getting spammed with "Your harvester appears to be offline" messages.

[pieterhelsen]

There's a branch currently in Pull Request that will likely solve this issue.
#164 closes this issue

[ghost]

Thank you, Pull request should definitely save this. Looking forward to the merge.

[Gr33nDrag0n69]

Thank you! I see the code was merged in dev branch, when can we expect an official release with this upgrade implemented?

[martomi]

Official release is out. This is hopefully resolved, please reopen issue if not.