nixos/traccar: traccar settings serializer does not properly escape stuff for the XML

[wucke13]

Nixpkgs version

• Stable (25.11)

Describe the bug

The traccar settings serializer does not properly escape strings.

Steps to reproduce

{
  services.traccar.settings.database.url = "jdbc:postgresql://localhost/traccar?socketFactory=org.newsclub.net.unix.AFUNIXSocketFactory$FactoryArg&socketFactoryArg=/var/run/postgresql/.s.PGSQL.5432";
}

leads to this snippet in the /var/lib/traccar/config.xml:

<entry key='database.url'>jdbc:postgresql://localhost/traccar?socketFactory=org.newsclub.net.unix.AFUNIXSocketFactory&socketFactoryArg=/var/run/postgresql/.s.PGSQL.5432</entry>

The $FactoryArg part is just removed, and the freestanding & actually should be an & within XML. Not good.

Expected behaviour

All settings are properly serialized into an XML file, such that the string that I put in via Nix is also the string perceived by the Java app reading that XML file (=traccar)

Screenshots

No response

Relevant log output

Additional context

The previous configuration mechanism for traccar was also broken, see #377804 .

System metadata

• system: "x86_64-linux"
• host os: Linux 6.18.2, NixOS, 25.11 (Xantusia), 25.11.20251229.89dbf01
• multi-user?: yes
• sandbox: yes
• version: nix-env (Lix, like Nix) 2.93.3 System type: x86_64-linux Additional system types: aarch64-linux, armv7l-linux, i686-linux Features: gc, signed-caches System configuration file: /etc/nix/nix.conf User configuration files: /home/wucke13/.config/nix/nix.conf:/etc/xdg/nix/nix.conf:/home/wucke13/.nix-profile/etc/xdg/nix/nix.conf:/nix/profile/etc/xdg/nix/nix.conf:/home/wucke13/.local/state/nix/profile/etc/xdg/nix/nix.conf:/etc/profiles/per-user/wucke13/etc/xdg/nix/nix.conf:/nix/var/nix/profiles/default/etc/xdg/nix/nix.conf:/run/current-system/sw/etc/xdg/nix/nix.conf Store directory: /nix/store State directory: /nix/var/nix Data directory: /nix/store/zp4ccr3fvndjx0dznjg7yf49xh68bdzw-lix-2.93.3/share
• nixpkgs: /etc/nix/inputs/nixpkgs

Notify maintainers

@frederictobiasc

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