Electron-updater: Appimage linux updater fails with ENOSYS: function not implemented

• Version: 4.1.2 (electron-updater)

• Target: Linux Appimage, Manjaro Linux

Electron updater errors out with the following logs:

Checking for update...
Found version 1.1.70727281 (url: sag-electron-1.1.70727281.AppImage)
Update available.
Downloading update from sag-electron-1.1.70727281.AppImage
updater cache dir: /home/elite/.cache/sag-electron-updater
Update has already been downloaded to /home/elite/.cache/sag-electron-updater/pending/sag-electron-1.1.70727281.AppImage).
Update downloaded; will install in 1 seconds
Auto install update on quit
Install: isSilent: true, isForceRunAfter: false
Error: Error: ENOSYS: function not implemented, unlink '/run/user/1000/appimagelauncherfs/0001.AppImage'
    at Object.unlinkSync (fs.js:1008:3)
    at AppImageUpdater.doInstall (/tmp/.mount_sag-elLEvSvQ/resources/app.asar/node_modules/electron-updater/out/AppImageUpdater.js:144:9)
    at AppImageUpdater.install (/tmp/.mount_sag-elLEvSvQ/resources/app.asar/node_modules/electron-updater/out/BaseUpdater.js:71:19)
    at /tmp/.mount_sag-elLEvSvQ/resources/app.asar/node_modules/electron-updater/out/BaseUpdater.js:104:12
    at App.<anonymous> (/tmp/.mount_sag-elLEvSvQ/resources/app.asar/node_modules/electron-updater/out/ElectronAppAdapter.js:60:48)
    at Object.onceWrapper (events.js:282:20)
    at App.emit (events.js:199:15)
    at App.<anonymous> (/tmp/.mount_sag-elLEvSvQ/resources/app.asar/main.js:41:42)
    at App.emit (events.js:199:15)

What’s interesting to note here is that /run/user/1000/appimagelauncherfs/ contains copies of appimages that are currently running. The error log implies that process.env.APPIMAGE does not return the path where the file was started from (by the user). I suspect that this is an issue with AppImageLauncher, which is the default method of integrating and running appimages on a lot of systems. This could easily be solved if there was some way of knowing what directory the appimage was actually started from.

Package.json: https://gitlab.com/nullworks/accgen/accgen-electron-app/blob/CD/package.json Node ver: v11.15.0 Npm ver: 6.10.0

[TheAssassin]

It’s sad to see zero reaction from the electron builder team. I’m not a fan reading when people (have to?) recommend users to uninstall AppImageLauncher entirely for some auto-update (which I’m not a fan of) or general updates to work as intended. If there were a workaround I could implement, that’d be no problem, but it’s really not that hard to fix the problem in the Electron updater itself.

The AppImage type 3 currently discussed here fixes the need for AppImageLauncher to ship with a custom FUSE filesystem which could cause trouble. binfmt_misc is to blame here, too.

@ozooner @mcous please recommend your users AppImageLauncher Lite instead of uninstalling AppImageLauncher entirely. The Lite version is not affected by this bug. And it provides at least some better desktop integration.

[mcous]

I believe this issue is still relevant. AppImageLauncher is recommended by electron-builder for desktop integration, but electron-updater does not work with AppImageLauncher installed AppImages