Template Variables (Macros)

Install scripts support several template variables that are dynamically replaced during processing:

$LOCATION(LocationId)

Resolves to user-configured or default paths for common directories.

Available Location IDs:

• ApplicationsPerformance - High-performance storage for app data
• ApplicationsCapacity - High-capacity storage for app data
• Downloads - Download directory
• Documents - Documents directory
• Media - General media storage
• Photos - Photo storage
• Music - Music storage
• Movies - Movie storage
• Shows - TV show storage
• Videos - Video storage
• VirtualizationPerformance - High-performance VM storage
• VirtualizationCapacity - High-capacity VM storage
• InstallMedia - Installation media storage
• VirtualDisks - Virtual disk storage

Example:

"path": "$LOCATION(ApplicationsPerformance)/plex/data"

$RANDOM_STRING(length)

Generates a random alphanumeric string of specified length. Useful for passwords, keys, and database names.

Example:

"password": "$RANDOM_STRING(12)"

$MEMORY(percentage, minimum_mb)

Dynamically allocates memory based on system resources. Takes the higher value between the percentage of system memory and the minimum specified in MB.

Example:

"memory": "$MEMORY(10%, 2048)"

This allocates either 10% of system memory or 2048MB, whichever is higher

$HOST_PATH(path)

Creates a TrueNAS host path configuration object for predefined storage options.

Example:

"storage": {
  "data": "$HOST_PATH($LOCATION(ApplicationsPerformance)/app/data)"
}

Expands to:

"storage": {
  "data": {
    "type": "host_path",
    "host_path_config": {
      "acl_enable": false,
      "path": "/mnt/pool/apps/app/data"
    }
  }
}

$MOUNTED_HOST_PATH(host_path, container_path)

Creates a TrueNAS host path configuration for additional storage mounts, mapping a host directory to a container path.

Example:

"additional_storage": [
  "$MOUNTED_HOST_PATH($LOCATION(Movies), /movies)",
  "$MOUNTED_HOST_PATH($LOCATION(Shows), /shows)"
]

Expands to:

"additional_storage": [
  {
    "type": "host_path",
    "read_only": false,
    "mount_path": "/movies",
    "host_path_config": {
      "acl_enable": false,
      "path": "/mnt/pool/movies"
    }
  }
]