TOPIC: FLATPAK
Removing obsolete libraries from Flatpak
1st February 2020Along with various pieces of software, Flatpak also installs KDE and GNOME libraries needed to support them. However, it does not always remove obsolete versions of those libraries whenever software gets updated. One result is that messages regarding obsolete versions of GNOME may be issued and this has been known to cause confusion because there is the GNOME instance that is part of a Linux distro like Ubuntu and using Flatpak adds another one for its software packages to use. My use of Linux Mint may lessen the chances of misunderstanding.
Thankfully, executing a single command will remove any obsolete Flatpak libraries so the messages no longer appear and there then is no need to touch your actual Linux installation. This then is the command that sorted it for me:
flatpak uninstall --unused && sudo flatpak repair
The first part that removes any unused libraries is run as a normal user, so there is no error in the above command. Administrative privileges are needed for the second section that does any repairs that are needed. It might be better if Flatpak did all this for you using the update command, but that is not how the thing works. At least, there is a quick way to address this state of affairs and there might be some good reasons for having things work as they do.
Ensuring that Flatpak remains up to date on Linux Mint 19.2
25th October 2019The Flatpak concept offers a useful way of getting the latest version of software like LibreOffice or GIMP on Linux machines because repositories are managed conservatively when it comes to the versions of included software. Ubuntu has Snaps, which are similar in concept. Both options bundle dependencies with the packaged software so that its operation can use later versions of system libraries than what may be available with a particular distribution.
However, even Flatpak depends on what is available through the repositories for a distribution, as I found when a software update needed a version of the tool. The solution was to add PPA using the following command and agreeing to the prompts that arise (answering Y, in other words):
sudo add-apt-repository ppa:alexlarsson/flatpak
With the new PPA instated, the usual apt commands were used to update the Flatpak package and continue with the required updates. Since then, all has gone smoothly as expected.
Getting Eclipse to start without incompatibility errors on Linux Mint 19.1
12th June 2019Recent curiosity about Java programming and Groovy scripting got me trying to start up the Eclipse IDE that I had installed on my main machine. What I got instead of a successful application startup was a message that included the following:
!MESSAGE Exception launching the Eclipse Platform:
!STACK
java.lang.ClassNotFoundException: org.eclipse.core.runtime.adaptor.EclipseStarter
at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:466)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:566)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:626)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
at org.eclipse.equinox.launcher.Main.main(Main.java:1414)
The cause was a mismatch between Eclipse and the installed version of Java that it needed to run. After all, the software itself is written in the Java language and the installed version from the usual software repositories was too old for Java 11. The solution turned out to be installing a newer version as a Snap (Ubuntu's answer to Flatpak). The following command did the needful since snapd already was running on my machine:
sudo snap install eclipse --classic
The only part of the command that warrants extra comment is the --classic switch, since that is needed for a tool like Eclipse that needs to access a host file system. On executing, the software was downloaded from Snapcraft and then installed within its own bundle of dependencies. The latter adds a certain detachment from the underlying Linux installation and ensures that no messages appear because of incompatibilities like the one near the start of this post.
Updating Flatpack applications on Linux Mint 19
10th August 2018Since upgrading to Linux Mint 19, I have installed some software from Flatpak. The cause for my curiosity was that you could have the latest versions of applications like GIMP or LibreOffice without having to depend on a third-party PPA. Installation is straightforward given the support built into Linux Mint. You just need to download the relevant package from the Flatpak website and run the file through the GUI installer. Because the packages come with extras to ensure cross-compatibility, more disk space is used, but there is no added system overhead beyond that, from what I have seen. Updating should be as easy as running the following single command too:
flatpak update
However, I needed to do a little extra work before this was possible. The first step was to update the configuration file at ~/.local/share/flatpak/repo/config to add the following lines:
[remote "flathub"]
gpg-verify=true
gpg-verify-summary=true
url=https://flathub.org/repo/
xa.title=Flathub
Once that was completed, I ran the following commands to import the required GPG key:
wget https://flathub.org/repo/flathub.gpg
flatpak --user remote-modify --gpg-import=flathub.gpg flathub
With this complete, I was able to run the update process and update any applications as necessary. After that first run, it has been integrated in to my normal processes by adding the command to the relevant alias definition.