Handlebars Support

Several fields in hermit.toml support Handlebars syntax for templating. This allows you to dynamically insert values into your configuration.

Standard Directory Variables

These variables are based on the directories crate and provide platform-appropriate paths.

Variable	Description	Linux/Unix	macOS	Windows
`{{dir.this}}`	Directory containing the current hermit.toml	Same on all platforms - absolute path to config directory
`{{dir.hermit}}`	Root hermit configuration directory	Same on all platforms - absolute path to hermit root
`{{dir.home}}`	User’s home directory	`$HOME` or `/home/username`	`$HOME` or `/Users/username`	`{FOLDERID_Profile}` or `C:\Users\username`
`{{dir.config}}`	User configuration directory	`$XDG_CONFIG_HOME` or `~/.config`	`$HOME/Library/Application Support`	`{FOLDERID_RoamingAppData}` or `C:\Users\username\AppData\Roaming`
`{{dir.data}}`	User data directory	`$XDG_DATA_HOME` or `~/.local/share`	`$HOME/Library/Application Support`	`{FOLDERID_RoamingAppData}` or `C:\Users\username\AppData\Roaming`
`{{dir.cache}}`	User cache directory	`$XDG_CACHE_HOME` or `~/.cache`	`$HOME/Library/Caches`	`{FOLDERID_LocalAppData}` or `C:\Users\username\AppData\Local`
`{{dir.state}}`	User state directory (optional)	`$XDG_STATE_HOME` or `~/.local/state`	Not available	Not available
`{{dir.preference}}`	User preferences directory	`$XDG_CONFIG_HOME` or `~/.config`	`$HOME/Library/Preferences`	`{FOLDERID_RoamingAppData}` or `C:\Users\username\AppData\Roaming`
`{{dir.runtime}}`	Runtime directory (optional)	`$XDG_RUNTIME_DIR`	Not available	Not available
`{{dir.executable}}`	User executables directory (optional)	`$XDG_BIN_HOME`, `$XDG_DATA_HOME/../bin` or `~/.local/bin`	Not available	Not available
`{{dir.config_local}}`	Local configuration directory	`$XDG_CONFIG_HOME` or `~/.config`	`$HOME/Library/Application Support`	`{FOLDERID_LocalAppData}` or `C:\Users\username\AppData\Local`
`{{dir.data_local}}`	Local data directory	`$XDG_DATA_HOME` or `~/.local/share`	`$HOME/Library/Application Support`	`{FOLDERID_LocalAppData}` or `C:\Users\username\AppData\Local`

XDG-Specific Variables

These variables are primarily for Linux/Unix systems and follow the XDG Base Directory Specification.

Variable	Environment Variable	Default on Linux	Notes
`{{dir.xdg_home}}`	`$XDG_HOME`	`$HOME`	Fallback to HOME if not set
`{{dir.xdg_config}}`	`$XDG_CONFIG_HOME`	`~/.config`	User configuration files
`{{dir.xdg_data}}`	`$XDG_DATA_HOME`	`~/.local/share`	User data files
`{{dir.xdg_cache}}`	`$XDG_CACHE_HOME`	`~/.cache`	User cache files
`{{dir.xdg_state}}`	`$XDG_STATE_HOME`	`~/.local/state`	User state files (logs, history, etc.)
`{{dir.xdg_bin}}`	`$XDG_BIN_HOME`	`~/.local/bin`	User executables
`{{dir.xdg_runtime}}`	`$XDG_RUNTIME_DIR`	(none)	Runtime files; only available if env var is set

Variables and Contexts

With Handlebars, you can access contextual information:

`var`

In an install action, the variables as specified in the hermit.toml:

name - The name of the install action

`tag`

The values of the detected tags as specified in tags:

arch - for example might be aarch64

`sys`

System information:

sys.cpu_num - Number of CPU cores
sys.mem_total - Total memory available

`env`

All environment variables are available through the env context. For example, {{env.PATH}} would access the $PATH environment variable.

`hermit`

HermitGrab-specific information:

hermit.version - The version of hermitgrab
hermit.exe - Absolute path to the hermitgrab executable
hermit.ubi - Absolute path to the hermitgrab executable plus the arguments to execute ubi commands

Helpers

The helper function snippet allows you to reference the contents of a defined snippet.

XDG Support