[GUI Plugin] calibre Auto-Updater

[dunhill]

Originally Posted by kovidgoyal

@dunhill: Note that on Windows shutdown running calibre is not sufficient it can leave viewer and edit windows around. There is no general method for shutting them down. You would need to use something like psutil to search for the processes and kill them and running shutdown running calibre.

@kovidgoyal,
Thank you very much for the technical tip regarding Windows child processes. Following your advice, I've updated the plugin to version 1.2.1.
Now, before launching the installer, the plugin uses taskkill to clean up any remaining instances of ebook-viewer.exe, ebook-edit.exe, and calibre-parallel.exe. This ensures the .msi installer doesn't run into "files in use" errors. I've also kept the --shutdown-running-calibre command to ensure the database closes gracefully first.
Thanks for keeping an eye on this!
I'm learning a lot from the comments.

[dunhill]

Originally Posted by JSWolf

One thing. If after doing the shutdown, are you are then waiting a specific time before starting the install? If so, what what about the varying time it can take to do the config backup with the backup plug-in?

@JSWolf,
That’s a very sharp observation. You are absolutely right—background tasks like the "Backup Default Settings" plugin or library metadata flushing need time to finish before the installer starts.
To address this, I've implemented a Smart Wait Loop in version 1.2.1. Instead of a fixed delay, the plugin now actively monitors the system process list and waits until calibre.exe has completely disappeared before proceeding. This way, any pending I/O or backup operations can finish safely.
Thanks for helping me make the plugin more robust!

[dunhill]

Originally Posted by Terisa de morgan

Thank you, it has worked for me now. I haven't checked the download folder change because I've updated before, but I'll do the next time. And thank you for the plugin, it simplifies the update.

@Terisa de Morgan,
You're very welcome! Actually, the option to change the download folder was a suggestion from @JSWolf.
After carefully analyzing the situation, I realized it was a great point and a very useful feature for those who like to keep their files organized. I always try to listen to suggestions to make the plugin as useful as possible for everyone, within the technical possibilities.
Glad it’s working well for you now!

[dunhill]

v1.2.1:

Improved Process Management (Windows): Based on feedback from @kovidgoyal, the plugin now proactively terminates child processes (ebook-viewer.exe, ebook-edit.exe, etc.) before launching the installer to prevent "file in use" errors.
Smart Wait Loop (Windows): Following @JSWolf's observation, I've implemented a monitoring loop that waits for calibre to fully release all database locks and background tasks (like metadata flushing or settings backups) before starting the update.
Enhanced Linux Experience: Better terminal handling for the restart process. The plugin now uses disown to ensure calibre restarts seamlessly after the update is finished.
Internationalization: Added full translations for French and Brazilian Portuguese.
Special thanks to the community members for their technical insights and testing!

[BetterRed]

Originally Posted by dunhill

Exactly. The plugin checks the OS but relies on the user having a standard installation. I've added a clear warning in the confirmation dialog stating that Portable, Flatpak, and AppImage versions are not supported and must be updated manually.

Since those versions don't follow the standard Windows Registry paths for the .msi installer, trying to automate them would lead to the 'Retry/Ignore' errors you mentioned. Keeping it restricted to official standard installs is the safest way to avoid corrupting a user's setup.

Please read what I actually wrote; it's about what is running when the msi installer is started, nothing to do with installing portable itself.

I've attached some screenshots - the executables that the portable launchers start are identical to the installed calibre executables, the difference is that they're loaded from a different location and some variables are set to precondition the execution environment.

I have no idea if that is relevant to your plugin. Knowing you don't use Windows, I wanted to make sure that you were aware that the msi installer will not run to completion if any of the calibre executables are running from a portable install.

Added: Perhaps you're not aware that 'installed calibre' and multiple copies of 'calibre portable' can coexist on the same Windows system.

BR

[JSWolf]

Originally Posted by dunhill

@JSWolf,
That’s a very sharp observation. You are absolutely right—background tasks like the "Backup Default Settings" plugin or library metadata flushing need time to finish before the installer starts.
To address this, I've implemented a Smart Wait Loop in version 1.2.1. Instead of a fixed delay, the plugin now actively monitors the system process list and waits until calibre.exe has completely disappeared before proceeding. This way, any pending I/O or backup operations can finish safely.
Thanks for helping me make the plugin more robust!

Happy to help.

[dunhill]

Originally Posted by BetterRed

Please read what I actually wrote; it's about what is running when the msi installer is started, nothing to do with installing portable itself.

I've attached some screenshots - the executables that the portable launchers start are identical to the installed calibre executables, the difference is that they're loaded from a different location and some variables are set to precondition the execution environment.

I have no idea if that is relevant to your plugin. Knowing you don't use Windows, I wanted to make sure that you were aware that the msi installer will not run to completion if any of the calibre executables are running from a portable install.

Added: Perhaps you're not aware that 'installed calibre' and multiple copies of 'calibre portable' can coexist on the same Windows system.

BR

@BetterRed,

Thank you for the detailed explanation and the screenshots! I now see exactly what you mean: since the executables share the same names regardless of their location, the MSI installer will trigger a conflict if any of them are active.
Even though I'm on Linux, the plugin's logic for Windows actually accounts for this. It uses image name filtering (e.g., taskkill /IM calibre-parallel.exe) rather than specific file paths.
This means that even if a user is running a Portable version from a different drive, the plugin will detect those processes by name, attempt to close them, and wait for them to disappear before launching the MSI.
So, thanks to your observation, I can confirm that version 1.2.1 is safer than ever!

[fogice]

I installed v.1.2.1 yesterday and ran it on my Mac (macOS 26.3.1). It successfully downloaded the disk image and mounted it, but it did not close Calibre. I did not see any messages or notifications in Calibre about quitting the app either.

[dunhill]

Originally Posted by fogice

I installed v.1.2.1 yesterday and ran it on my Mac (macOS 26.3.1). It successfully downloaded the disk image and mounted it, but it did not close Calibre. I did not see any messages or notifications in Calibre about quitting the app either.

@fogice,
Thank you for your feedback and for reporting your macOS version (26.3.1).
Currently, the plugin's behavior on macOS is slightly different from Windows. While on Windows we force-close all related processes to avoid installer conflicts, on macOS the plugin sends a "quit" signal to the GUI and opens the .dmg file.
It seems that in some environments, calibre might stay open if it's waiting for a background task to finish or if the system requires a manual confirmation. I will look into making the shutdown more consistent on macOS for the next update.
For now, once the disk image is mounted, you can manually close calibre and drag the new version to your Applications folder as usual. Thanks for testing!

[dunhill]

Changelog v1.2.1 -> v1.2.2:

macOS: Updated user instructions to reflect manual intervention. Since macOS security (Gatekeeper/Permissions) often prevents automated shutdowns and overwrites in /Applications, the plugin now guides the user to close calibre and perform the "drag and drop" manually after a successful download.

We have to acknowledge that macOS automation is inherently more restrictive than Windows or Linux. Due to Apple's Gatekeeper and strictly enforced permissions for the /Applications folder, forcing a silent overwrite (replace) often triggers system-level security alerts or requires manual 'sudo' intervention. To keep the plugin safe and reliable, we've opted for a guided manual process in this version. Note: Automated installation on macOS is currently limited by system security policies regarding the Applications folder. We prioritize stability and security over forced automation.

UI Polish: Rephrased dialog messages to be more accurate depending on the detected Operating System.

The message that will appear for mac users will be this
calibre Updater
Do you want to download the update?

IMPORTANT: This plugin is designed for official/standard installations (from the calibre website). If you use Flatpak, AppImage, or Portable versions, you must update them MANUALLY.

macOS Instructions: Please close calibre manually now. Then, locate the downloaded disk image (.dmg) in your configured folder, drag the calibre icon to your Applications folder and select "Replace" when prompted.

Note: The file will be saved in your Downloads folder unless a custom path is set in the plugin configuration.

You can check the latest changes here:
https://calibre-ebook.com/whats-new



We are definitely aiming for full automation on macOS in future releases. However, as I don't have a physical Mac for testing, I am currently limited in debugging the exact sequence to force-close the UI and handle the file move to /Applications without triggering security alerts.

Just as the Windows automation was refined thanks to valuable community feedback and technical tips regarding process handling, I am completely open to suggestions from the macOS

[dunhill]

Calibre plugin behavior on macOS: A friend performed the installation, and these were the steps: 1. I clicked the "Update calibre" icon in the menu.
This window appeared (image 1).
2. I clicked "Yes." calibre closed, and...
This message appeared (image 2).
3. I clicked "Accept," and "calibre 9.5.0" was downloaded. It opened, and this window appeared on the desktop (image 3).
And from the last window, you drag it to Applications.

[Lavender]

I'm trying to test the plugin now that a new Calibre release is available, but it's not functioning as expected on my Kubuntu 25.10 system. I have the official Calibre 9.5 installed. I installed v1.2.2 of the plugin via the zip file, and the plugin shows in the dialogue window when I click the updater icon in the menu bar. After clicking yes, Calibre is closed and nothing happens. My terminal doesn't open, and when I relaunch Calibre, it has not been updated.

[dunhill]

Originally Posted by Lavender

I'm trying to test the plugin now that a new Calibre release is available, but it's not functioning as expected on my Kubuntu 25.10 system. I have the official Calibre 9.5 installed. I installed v1.2.2 of the plugin via the zip file, and the plugin shows in the dialogue window when I click the updater icon in the menu bar. After clicking yes, Calibre is closed and nothing happens. My terminal doesn't open, and when I relaunch Calibre, it has not been updated.

Hi Lavender, thank you so much for your detailed report!

You hit the nail on the head. The issue was that the plugin wasn't looking for Konsole (the default terminal in Kubuntu/KDE) and was failing to launch the update script before closing calibre.

I have just released v1.2.3 which includes:

KDE/Konsole Support: Added specific compatibility for Kubuntu and other Plasma-based distros.

Fail-safe Launch: calibre will no longer close unless the terminal successfully starts. If no terminal is found, you'll see an error message instead of the app just disappearing.

macOS Refinements: Small internal changes to improve the manual update flow.

Please try this new version and let me know if it works on your Kubuntu 25.10 system. Your feedback is what makes this plugin better!

[Lavender]

Originally Posted by dunhill

Hi Lavender, thank you so much for your detailed report!

You hit the nail on the head. The issue was that the plugin wasn't looking for Konsole (the default terminal in Kubuntu/KDE) and was failing to launch the update script before closing calibre.

I have just released v1.2.3 which includes:

KDE/Konsole Support: Added specific compatibility for Kubuntu and other Plasma-based distros.

Fail-safe Launch: calibre will no longer close unless the terminal successfully starts. If no terminal is found, you'll see an error message instead of the app just disappearing.

macOS Refinements: Small internal changes to improve the manual update flow.

Please try this new version and let me know if it works on your Kubuntu 25.10 system. Your feedback is what makes this plugin better!

Thank you for your reply. I uninstalled the old version of the plugin, and installed the new one. I'm not seeing any behaviour change though. I have Konsole installed, but it's not being launched. After selecting the plugin's GUI icon in my main toolbar of Calibre, the dialogue window opens, I click "yes", and then Calibre closes. Happy to offer any info if I can help.

[dunhill]

Originally Posted by Lavender

Thank you for your reply. I uninstalled the old version of the plugin, and installed the new one. I'm not seeing any behaviour change though. I have Konsole installed, but it's not being launched. After selecting the plugin's GUI icon in my main toolbar of Calibre, the dialogue window opens, I click "yes", and then Calibre closes. Happy to offer any info if I can help.

Hi Lavender, thank you for the feedback. It seems Kubuntu is closing the terminal session as soon as calibre exits (the 'parent' process killing the 'child').

I've prepared v1.2.4 with two specific fixes for KDE:
Process Detachment: Added a 'setpgrp' flag so the terminal becomes independent of calibre.
Konsole Persistence: Added the --noclose flag which is sometimes required in newer KDE versions to keep the window visible.
If this still doesn't show the terminal, could you please try running calibre from a terminal yourself, try to update, and copy here any error message that appears in the background? That would be incredibly helpful!