What is a chain command

A chain command is a custom command that help you automate multiple command execution, allowing you to define and read an external YAML file containing the definition name, options and arguments of multiple commands and execute that list based on the sequence defined in the file.

Chain command features:

Discovery of YAML files

Chains commands are discovered from the following path(s):

Globally ~/.console/chain
Per site path/to/site/console/chain

Define placeholders

You can define placeholders using {{name}} and you can pass a --key=value from the CLI as command option --name=[VALUE] when executing the command.

If you define placeholders and not pass a value for it using the CLI. This will be converted to a question during the interactive mode execution.

commands:
  # Create Drupal project using DrupalComposer
  - command: exec
    arguments:
      bin: composer create-project {{repository}} {{directory}} --prefer-dist --no-progress --no-interaction
  # Install Drupal
  - command: exec
    arguments:
      bin: drupal site:install {{profile}} --root={{directory}} --db-type="sqlite" --no-interaction
  # Start PHP built-in server
  - command: exec
    arguments:
      bin: drupal server --root={{directory}}

Set default values for placeholders

You can use the variables section to define default values for placeholders.

vars:
  repository:
    - drupal-composer/drupal-project:8.x-dev
    - acquia/lightning-project
    - acquia/reservoir-project
  profile: standard

You can define placeholders as single value or as an array. This definition will be used to decide the type of question generated when executing this command using the interactive mode.

Read environment variables:

You can read environment variables using {{ env("ENVIRONMENT_VAR_NAME") }}.

command:
  name: site:install:env
  description: 'Install site using environment placeholders'
commands:
  # Install Drupal
  - command: site:install
    options:
      langcode: en
      db-type: '{{ env("DATABASE_TYPE") }}'
      db-host: '{{ env("DATABASE_HOST") }}'
      db-name: '{{ env("DATABASE_NAME") }}'
      db-user: '{{ env("DATABASE_USER") }}'
      db-pass: '{{ env("DATABASE_PASSWORD") }}'
      db-port: '{{ env("DATABASE_PORT") }}'
      site-name: 'Drupal 8 site'
      site-mail: admin@example.org # default email
      account-name: admin # default account
      account-mail: admin@example.org # default email
      account-pass: admin # default pass
    arguments:
      profile: 'standard'

All of the required environment variables used on a chain command definition are mandatory.