New Docker Stack Task Info Module with Tests (#732)

* Add docker_stack_task_info with tests

* Change link

* Change ln

* Fix Documentation

* Small doc changes

* Remove node for RH

(cherry picked from commit 107e956565)

tests/integration/targets/docker_stack_task_info/tasks/main.yml

@@ -0,0 +1,5 @@
+- include_tasks: test_stack_task_info.yml
+  when: docker_api_version is version('1.25', '>=')
+
+- fail: msg="Too old docker / docker-py version to run docker_stack tests!"
+  when: not(docker_api_version is version('1.25', '>=')) and (ansible_distribution != 'CentOS' or ansible_distribution_major_version|int > 6)

tests/integration/targets/docker_stack_task_info/tasks/test_stack_task_info.yml

@@ -0,0 +1,80 @@
+---
+- block:
+  - name: Make sure we're not already using Docker swarm
+    docker_swarm:
+      state: absent
+      force: true
+
+  - name: Get docker_stack_info when docker is not running in swarm mode
+    docker_stack_info:
+    ignore_errors: true
+    register: output
+
+  - name: Assert failure when called when swarm is not running
+    assert:
+      that:
+        - 'output is failed'
+        - '"Error running docker stack" in output.msg'
+
+  - name: Create a swarm cluster
+    docker_swarm:
+      state: present
+      advertise_addr: "{{ ansible_default_ipv4.address }}"
+
+  - name: Get docker_stack_info when docker is running and not stack available
+    docker_stack_info:
+    register: output
+
+  - name: Assert stack facts
+    assert:
+      that:
+        - 'output.results | type_debug == "list"'
+        - 'output.results | length == 0'
+
+  - name: Copy compose files
+    copy:
+      src: "{{ item }}"
+      dest: "{{ output_dir }}/"
+    with_items:
+      - stack_compose_base.yml
+      - stack_compose_overrides.yml
+
+  - name: Install docker_stack python requirements
+    pip:
+      name: jsondiff,pyyaml
+
+  - name: Create stack with compose file
+    register: output
+    docker_stack:
+      state: present
+      name: test_stack
+      compose:
+        - "{{ output_dir }}/stack_compose_base.yml"
+
+  - name: Assert test_stack changed on stack creation with compose file
+    assert:
+      that:
+        - output is changed
+
+  - name: Get docker_stack_info when docker is running
+    docker_stack_info:
+    register: output
+
+  - name: Get docker_stack_task_info first element
+    docker_stack_task_info:
+      name: "{{ output.results[0].Name }}"
+    register: output
+
+  - name: assert stack facts
+    assert:
+      that:
+        - 'output.results | type_debug == "list"'
+        - 'output.results[0].DesiredState == "Running"'
+        - 'output.results[0].Image == "busybox:latest"'
+        - 'output.results[0].Name == "test_stack_busybox.1"'
+
+  always:
+    - name: Cleanup
+      docker_swarm:
+        state: absent
+        force: true