How can I use paths an filenames containing variables?

[lwbt]

Hello, I would like to include a file like the following into my dotfiles:

.local/share/Steam/userdata/${steam_account_id}/config/preferences_${controller_serial_number}.vdf

• ${steam_account_id} is a large number
• ${controller_serial_number} is an alphanumerical string
  • Serial number in this particular case a is the serial number of the host device (a Steam Deck) and printed at least on the outside of the cardboard box it was shipped in.

After checking the documentation and threads like #3333 and #1226 it is not clear to me how to do it. I'd prefer a simple way like having steam_account_id and controller_serial_number in my chezmoi data section and use a paths with variables like above.

[Lockszmith-GH]

Not sure if this is the only approach, but seems to me you want to preserve the contendt of the .vdf file, but have it a different name on different machines / user profiles.

If that's the goal, one approach can be to maintain a master_controller_preference.vdf file and create a symbolic-link to it with a shell (or PowerShell) script with a run_once_... script.

[twpayne]

There's currently no way to do this elegantly. I would recommend using a run_ script as @Lockszmith-GH suggests. This can be a template:

#!/bin/bash
# .local/share/chezmoi/run_configure-steam-controllers.tmpl

mkdir -p "$HOME/.local/share/Steam/{{ .steamAccountID }}"
cp .local/share/chezmoi/.preferences.vdf "$HOME/.local/share/Steam/{{ .steamAccountID }}/preferences_{{ .controllerSerialNumber}.vdf"

Where .steamAccountID and .controllerSerialNumber are template variables set in the data section of your config file, and .local/share/chezmoi/.preferences.vdf is a file containing the desired preferences.

This should be a run_ script, not a run_once_ script, as it needs to run every time to update the files in case they have changed.

Longer term, #2273 will be the eventual elegant solution.

[lwbt]

Thank you for your suggestions and examples.

To give a more complete example, let's say I have more than one file:

.local/share/Steam/userdata/${steam_account_id}/config/preferences_${controller_serial_number}.vdf
.local/share/Steam/userdata/${steam_account_id}/config/a_few_more_files.vdf

Combining both of your answers I thought of a script like this: run_after_configure-steam-controllers.tmpl

#!/bin/bash

# Create a symlink from folder with placeholder name to the actual account ID for steam
ln -sf "__steamAccountID" "$HOME/.local/share/Steam/{{ .steamAccountID }}"

# Create symlinks for files with placeholders in their names in the same directory
ln -sf "preferences__controllerSerialNumber.vdf" \
  "$HOME/.local/share/Steam/{{ .steamAccountID }}/preferences_{{ .controllerSerialNumber}.vdf"

So I let Chezmoi copy the folder and all its files with a placeholder name on the same level in the folder hierarchy. Then I create a symbolic link with the proper name that the application expects, and then I create symbolic links for individual files where necessary. It's semi-elegant, or just good enough.

I spent some more time catching up with the changes in documentation and some discussions here. I read that symbolic links for folders are not read in the source state for technical reasons and security, but on the targets this should be fine? Or will I run into some other issues of Chezmoi?

[Lockszmith-GH]

You can do both copy and symlink, or just copy actually.

With twpayne's suggestion you don't need symlinks at all actually, all you need is a directory .preferences.vdf in your chezmoi git repo, it will not be copied over automatically.

With the symlink approach, you are right - a copy will be managed by chezmoi somewhere in your home directory, and the symlinks will point to files/folders.

Note, in your code, after you symlink the directory, it will fill that directory with additioal (symlinked) 'files' - not sure that is a desired effect. So that makes tpayne's solution a bit 'more elegant'.

Since these are generally small files, I think you should be safe with the small files. But keep in mind that you should always edit the git repo copy, and then chezmoi apply to apply the changes.