A bit lost: how to handle prompt driven data

[rsanheim]

I'm a bit lost on how to accomplish something I know is possible with chezmoi, but I haven't seen a good 'how to' or 'recipe' driven guide for how to do this.

I have an existing chezmoi setup for two machines, and expanding it to more. I'd like to have chezmoi conditionally install some packages based on user input. For example, lets say I want to install jj only on some machines, and I just want to decide based on a prompt. I think that means that the desired end-state is one where I end with chezmoi.toml in my chezmoi config:

[data]
  installJJ = [ true | false ] # based on user input

so I add this to .chezmoi.toml.tmpl

{{- $installJJ = promptBoolOnce . "installJJ" "Install jj on this machine" -}}

[data]
    installJJ = {{ $installJJ }}

I then change scripts or my Brewfile or whatever in chezmoi to use {{ $installJJ }}, but they all fail with the map has no entry for key. My understanding is this is due to the order of when things get run in init.

Am I doing this incorrectly? Is there a better way to handle this sort of 'optional user-driven' config? I've read thru https://www.chezmoi.io/user-guide/setup/#re-create-your-config-file and https://www.chezmoi.io/reference/special-files/chezmoidata-format/ and related docs, but I'm a bit lost at how to add this to an existing setup.

[2-4601]

Does your actual chezmoi config file (e.g. $XDG_CONFIG_HOME/chezmoi/chezmoi.toml) have a value for installJJ?

Based on your example, it should appear there after you run chezmoi init and then answer the prompt.

And after your chezmoi.toml file has been created with a boolean value for installJJ, then chezmoi apply should run your (template) scripts and you should be able to access the boolean value with key .installJJ.

[rsanheim]

I think this is the core of the issue -- its a bootstrap issue where I want to add have templates depend on data (for deciding to install a pkg in this case), but if that data itself is managed via chezmoi it won't exist anywhere on a first init that requires the data.

So maybe the missing piece is some static file to set defaults for data, which gets overrided by user input and stored in [data] ?

basically some pattern for managing this that doesn't involve adding conditionals throughout templates to handle the bootstrap issue.

[2-4601]

Installing packages via scripts that use data from chezmoi's configuration file is a very common use case and it should work.

I tried the following from scratch:

$ ls -la ~/.local/share/chezmoi
ls: cannot access ~/.local/share/chezmoi: No such file or directory

$ chezmoi cd

Create .chezmoi.toml.tmpl

$ cat .chezmoi.toml.tmpl
{{- $installJJ := promptBoolOnce . "installJJ" "Install jj on this machine" false -}}

[data]
    installJJ = {{ $installJJ }}

$ cat ~/.config/chezmoi/chezmoi.toml
cat: ~/.config/chezmoi/chezmoi.toml: No such file or directory

$ chezmoi init
Install jj on this machine? bool, default false Y

$ cat ~/.config/chezmoi/chezmoi.toml
[data]
    installJJ = true

Create run_onchange_before_install-packages.sh.tmpl

$ cat run_onchange_before_install-packages.sh.tmpl
#!{{ lookPath "bash" }}
{{ if .installJJ }}
echo "Installing jj..."
{{ end }}

$ chezmoi apply
Installing jj...

Is the above something you are trying to do or am I missing something here 🤔

[halostatue]

{{- $installJJ := promptBoolOnce . "installJJ" "Install jj on this machine" -}}

[data]
    installJJ = {{ $installJJ }}

I'm not sure if this is your problem, but you need to force variable creation with := unless you have a section which does {{- $installJJ := false -}}.