templates¶

Renders Go text/template files with config-supplied variables and writes the result to a destination path.

What it does¶

For each configured template entry:

1. Reads the source file and parses it as a Go text/template.
2. Executes the template with the configured variables.
3. Writes the rendered output to the destination path.

If the destination already exists, the rendered output is written to <destination>.new instead. Existing files are never overwritten.

Config¶

templates:
  enabled: true
  templates:
    - source: /boot/firmware/templates/app.conf.tpl
      destination: /etc/app/app.conf
      chmod: "640"
      variables:
        listen_address: "127.0.0.1"
        port: "8080"
        log_level: "info"

Template syntax¶

Templates use Go's text/template syntax. Variables are accessed with dot notation:

# app.conf.tpl
listen = {{ .listen_address }}:{{ .port }}
log_level = {{ .log_level }}

Renders to:

# app.conf
listen = 127.0.0.1:8080
log_level = info

Missing keys are fatal. If a variable referenced in the template is not present in variables, the module fails with an error. This is enforced via missingkey=error so typos and missing entries are caught early.

Dry-run¶

In dry-run mode, the template is still parsed and executed — syntax errors and missing variables are reported — but nothing is written to disk.

INFO [templates] would render /boot/firmware/templates/app.conf.tpl → /etc/app/app.conf (dry-run)

This means bootconf run --dry-run catches template errors before the next real boot.

Permissions¶

The rendered file is written as root:root. The chmod value is applied after writing. Values above 0777 are rejected.

vs. files¶

Use files when you want to place a static file as-is. Use templates when the content needs to be generated from variables that differ between deployments.