Signal-desktop: Linux/Snap: Support underlying directories moved around at runtime

[bast1aan]

• [X] I have searched open and closed issues for duplicates
  

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Bug Description

The Signal Desktop Snap app in Ubuntu 18.04 crashes after a running for a while with following error message:

Unhandled Error

Error: EACCES: permission denied, rename '/home/bwelmers/snap/signal-desktop/219/.config/Signal/logs/log.log.1' -> '/home/bwelmers/snap/signal-desktop/219/.config/Signal/logs/log.log.2'

When looking in the list of Signal snap versions:

/dev/loop7                              98M   98M     0 100% /snap/signal-desktop/219
/dev/loop10                             98M   98M     0 100% /snap/signal-desktop/235

it looks like the snap is upgraded in the background and somehow the running instance of Signal does not handle this correctly and keeps trying to use the older config directory.

Steps to Reproduce

Unfortunately not easy, but something like this

1. install signal-desktop snap app and launch it, login to it, use it etc
2. let it run until a new version is installed by snapd
3. wait until the log needs to be rotated. Looks like that is done on daily basis.

Actual Result:

Crash

Expected Result:

Should not crash.

Screenshots

Platform Info

Signal Version:

$ snap list signal-desktop Name Version Rev Tracking Publisher Notes signal-desktop 1.29.0 235 stable snapcrafters -
Operating System:

Ubuntu 18.04

Linked Device Version:

Android: Signal 4.49.18

Link to Debug Log

https://debuglogs.org/604b3bb6f1cc01244899b902643643d3503981433d3377526d5f671b96b89c12

[bast1aan]

Duplicated issue to https://github.com/snapcrafters/signal-desktop/issues/14 as well

[bajhn]

I am not so sure that an upgrade is necessary for the EACCES error on renaming the logs. I received the error this morning on a Linux Mint system that's been up for 4 days, and I cannot find any evidence that snap or signal was upgraded. The error occurred sometime between 5-dec-19 17:40 (local time, -05:00) and 6-dec-19 09:40. My dpkg.log ends at 5-dec-19 15:35. The journal shows that Snappy daemon restarted at 5-dec-19 11:34, and I don't remember restarting Signal since several days ago. I'm attaching journal output for snapd and the Signal logs. This hasn't happened in a while, but I'll be happy to provide any other info if it's useful.
signal-logs.tar.gz
snapd.service.log.gz

[scottnonnenberg-signal]

We don't need logs - we need the structure and permissions of Signal-related directories when this happens. And ideally, what it was before. The theory is that this is due to directories being moved or deleted.

[Cristian-Bejan]

Same as @bast1aan ; snap made an update from 1.30.1 -> 1.31.0

Unhandled Error

Error: EACCES: permission denied, rename '/home/blabla/snap/signal-desktop/298/.config/Signal/logs/log.log' -> '/home/blabla/snap/signal-desktop/298/.config/Signal/logs/log.log.0'

[angelgruevski]

same issue here too.

[scottnonnenberg-signal]

Thanks for your input, everyone. I want to be very clear - as of today we don't officially support the Signal Desktop snap packages available now.

[angelgruevski]

Will you support the Debian package or are you dropping support for that too?

[scottnonnenberg-signal]

If this bug is reproducing for you outside the context of a snap package, please enter a new bug.

[johnmee]

It is trying to rotate the log file; (rename "log.log" to "log.log.0" then continue to writing to log.log) however the "home" plug does not have permission to do it. Is the fix just to add the log directory with "write" permission in the snapcraft.yaml?

https://snapcraft.io/docs/personal-files-interface

[dasistwas]

Bug still there one year later:

Unhandled Error

Error: EACCES: permission denied, rename '/home/user/snap/signal-desktop/349/.config/Signal/logs/log.log.1' -> '/home/user/snap/signal-desktop/349/.config/Signal/logs/log.log.2'

[bajhn]

FWIW, I've been using the flatpak distribution from Linux Mint 20 for awhile now, and I haven't seen this error any longer. I had to uninstall the snap for it on one of my machines.