first part of config

roles/docker-swarm-add-worker/tasks/main.yml

@@ -0,0 +1,16 @@
+---
+- name: Check node state.
+  register: node_state
+  shell: "docker info --format '{{ '{{' }}.Swarm.LocalNodeState{{ '}}' }}'"
+  ignore_errors: true
+
+- name: Add worker to swarm.
+  register: join_cmd
+  shell: >
+    docker swarm join
+    --token {{ hostvars.admin.worker_token }}
+    {{ hostvars.admin.ansible_host }}:2377
+  # 0 means it was successfully added, 1 means it's already in the swarm.
+  failed_when: join_cmd.rc != 0
+  changed_when: join_cmd.rc == 0
+  when: node_state.stdout not in [ 'active', 'locked', 'error' ]