Templates

Overview

Each developer environment or Template, is defined by a Nomad job and optional volume definition.

When a developer creates an instance of the Template, a space, and starts it, knot automatically creates any required volumes and launches the job within the Nomad cluster.

For additional isolation between developers the namespace can be set within the job specification, e.g. namespace="${{ .user.username }}", if this is done then jobs for each developer are placed within their own namespaces.

Creating a Template

From the menu select Templates then Create Template, the following form is displayed:

The Name and Nomad Job fields are required, the Nomad Job field takes an HCL job specification, see example environments.

ℹ️

When a change is made to a template all running spaces are marked as an update available, however the spaces are not automatically restarted. Once the spaces are restarted they will receive the updated template.

Template variables can be used to hold registry login information e.g.

image = "paularlott/knot-debian:12"
auth {
  username = "${{ .var.registry_user }}"
  password = "${{ .var.registry_pass }}"
}

⚠️

Variables are plain text within the Nomad template and can therefore be viewed via the Nomad web interface, and alternative solution such at Vault may be more applicable depending on the environment.

Deleting a Template

If a template is in use then it can’t be deleted.

Groups User Management