32 service image push (#33)

* [SAS-5484] Started working, but moving to our ansible host.

* #32 - Concept working.

* #32 - Forgot the playbook  itself.

roles/docker_login/tasks/main.yml

@@ -7,3 +7,4 @@
   become_user: "{{ docker_become_user|default(omit) }}"
   loop: "{{ groups['docker_nodes'] }}"
   delegate_to: "{{ item }}"
+  run_once: true

roles/docker_service_image_push/meta/main.yml

@@ -0,0 +1,2 @@
+dependencies:
+  - role: docker_login

roles/docker_service_image_push/tasks/main.yml

@@ -0,0 +1,36 @@
+- name: docker image inspect - all nodes
+  command:
+    cmd: "docker image inspect {{ repository_deploy_image }}"
+  become: "{{ docker_become_user is defined }}"
+  become_user: "{{ docker_become_user|default(omit) }}"
+  loop: "{{ groups['docker_swarm_nodes'] }}"
+  loop_control:
+    loop_var: docker_swarm_node
+    label: "{{ docker_swarm_node }}"
+  delegate_to: "{{ docker_swarm_node }}"
+  register: image_inspect_result
+  failed_when: false
+
+- name: look for any successful image_inspect_result
+  set_fact:
+    image_inspect_results_successful_node: "{{ item.docker_swarm_node }}"
+  loop: "{{ image_inspect_result.results }}"
+  loop_control:
+    label: "{{ item.docker_swarm_node }}"
+  when: item.rc == 0
+
+- name: ensure a successful node was found
+  assert:
+    that:
+      - image_inspect_results_successful_node is defined
+
+# the docker_image builtin provided by ansible is tricky to coerce into pushing when no other changes are necessary
+# in image_push we untag the image, then tag/push at the same time
+# since this role is intended to be run against a production service, we don't want to untag images in it
+# so we just use the command module instead
+- name: docker image push - found node
+  command:
+    cmd: "docker image push {{ repository_deploy_image }}"
+  become: "{{ docker_become_user is defined }}"
+  become_user: "{{ docker_become_user|default(omit) }}"
+  delegate_to: "{{ image_inspect_results_successful_node }}"

service-image-push.yml

@@ -0,0 +1,5 @@
+- hosts: docker_services
+  # nothing here should rely on gathered facts
+  gather_facts: no
+  roles:
+    - role: docker_service_image_push