QLI-Installer: Installing official Qt-builds from the command line

23 Dec 2018

As you probably know, Qt provides many builds for different systems and architectures. They can be very useful, if you want to develop with the latest libraries, even if your distro doesn’t provide them (or if you’re using Windows/Mac and you got no Qt at all). In my I case I wanted to use the latest Qt on an LTS CI system. I know that there are PPAs for Ubuntu, however, if you want to use the Qt for Android builds, there’s really no other way: either you compile everything yourself or you need to use the official installer.

There’s just one problem: Qt only provides a graphical installer, which can’t be on a server. This has been a problem for a long time and there are some workarounds using the Qt scripting interface with a virtual display, but that workaround isn’t that easy to use and error-prone. You can find an example of this on stackoverflow.

Since the Qt Installer basically only lets you select the Qt version and then downloads & extracts everything, I thought that it couldn’t be too hard to rewrite that in a simple script. I browsed a bit through the Qt installer repository and started to write a python script that should output the URLs for a specific Qt version. Turns out: the URLs are not consistent in all Qt versions and they contain long build numbers. To solve this I needed to parse the Updates.xml file for each target/version. These files list all the packages and their dependencies. From these we only need the main package (it contains most modules as QtCore, QtSql, QtSvg and many more, only QtCharts and similar are missing) and can ignore its dependencies (it only depends on the qtcreator, documentation and examples, which we all don’t need for our purpose).

In the end I came up with a python script that can download and extract you every Qt version you want (even iOS builds can be downloaded on a Linux host system, which wasn’t possible before :D). The script (currently) just calls the p7zip commands for extracting the packages which isn’t optimal, but OK.

So if you would like to use the official Qt builds on a server and don’t want to argue with the graphical installer, you might want to try my script. It’s available on my GitLab instance. Here is an example how to use it on debian-based systems:

sudo apt install python3-requests p7zip-full wget

wget https://git.kaidan.im/lnj/qli-installer/raw/master/qli-installer.py
chmod +x qli-installer.py

./qli-installer.py 5.12.0 linux desktop

This will download and extract Qt 5.12.0 to a folder called 5.12.0 in your current directory. You can find more details in the README. If you have any suggestions or you’ve found a bug (the installer repository format changes from time to time), please submit an issue.

Qt