Add gitlab_runner_docker_image option

Author: haroldb

README.md

@@ -31,6 +31,9 @@ Defaults to the hostname.
 The executor used by the runner.
 Defaults to `shell`.
 
+`gitlab_runner_docker_image`
+The default Docker image to use. Required when executor is `docker`.
+
 `gitlab_runner_tags`
 The tags assigned to the runner,
 Defaults to an empty list.

defaults/main.yml

@@ -10,5 +10,7 @@ gitlab_runner_registration_token: ''
 gitlab_runner_description: '{{ ansible_hostname }}'
 # Runner executor
 gitlab_runner_executor: 'shell'
+# Default Docker image
+gitlab_runner_docker_image: ''
 # Runner tags
 gitlab_runner_tags: []

tasks/register-runner.yml

@@ -12,4 +12,5 @@
     --description '{{ gitlab_runner_description }}'
     --tag-list '{{ gitlab_runner_tags | join(",") }}'
     --executor '{{ gitlab_runner_executor }}'
+    --docker-image '{{ gitlab_runner_docker_image }}'
   when: configured_runners.stderr.find('\n{{ gitlab_runner_description }}') == -1