docker_node_facts: Read information about swarm node from swarm manager (#50571)

* docker_node_facts: New module to read information about swarm node from swarm manager

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

* docker_node_facts: min_docker_api_version and docker updated to align with Docker documentation

* docker_node_facts: Updated documentation and minimum version requirements

* docker_node_facts: Updated documentation of requirements

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

* Update lib/ansible/modules/cloud/docker/docker_node_facts.py

Co-Authored-By: WojciechowskiPiotr <23406016+WojciechowskiPiotr@users.noreply.github.com>

lib/ansible/modules/cloud/docker/docker_node_facts.py

@@ -0,0 +1,123 @@
+#!/usr/bin/python
+#
+# (c) 2019 Piotr Wojciechowski <piotr@it-playground.pl>
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+
+from __future__ import absolute_import, division, print_function
+__metaclass__ = type
+
+
+ANSIBLE_METADATA = {'metadata_version': '1.1',
+                    'status': ['preview'],
+                    'supported_by': 'community'}
+
+
+DOCUMENTATION = '''
+---
+module: docker_node_facts
+
+short_description: Retrieves facts about docker swarm node from Swarm Manager
+
+description:
+  - Retrieves facts about a docker node.
+  - Essentially returns the output of C(docker node inspect <name>).
+  - Must be executed on a host running as Swarm Manager, otherwise the module will fail.
+
+version_added: "2.8"
+
+options:
+  name:
+    description:
+      - The name of the node to inspect.
+      - When identifying an existing node name may either the hostname of the node (as registered in Swarm) or node ID.
+    required: true
+extends_documentation_fragment:
+    - docker
+
+author:
+    - Piotr Wojciechowski (@wojciechowskipiotr)
+
+requirements:
+    - "python >= 2.6"
+    - "docker-py >= 1.10.0"
+    - "Please note that the L(docker-py,https://pypi.org/project/docker-py/) Python
+       module has been superseded by L(docker,https://pypi.org/project/docker/)
+       (see L(here,https://github.com/docker/docker-py/issues/1310) for details).
+       For Python 2.6, C(docker-py) must be used. Otherwise, it is recommended to
+       install the C(docker) Python module. Note that both modules should I(not)
+       be installed at the same time. Also note that when both modules are installed
+       and one of them is uninstalled, the other might no longer function and a
+       reinstall of it is required."
+    - "Docker API >= 1.24"
+'''
+
+EXAMPLES = '''
+- name: Get info on node
+  docker_node_facts:
+    name: mynode
+  register: result
+
+'''
+
+RETURN = '''
+exists:
+    description:
+      - Returns whether the node exists in docker swarm cluster.
+    type: bool
+    returned: always
+    sample: true
+node_facts:
+    description:
+      - Facts representing the current state of the node. Matches the C(docker node inspect) output.
+      - Will be C(None) if node does not exist.
+    returned: always
+    type: dict
+
+'''
+
+from ansible.module_utils.docker_common import AnsibleDockerClient
+from ansible.module_utils._text import to_native
+
+try:
+    from docker.errors import APIError, NotFound
+except ImportError:
+    # missing docker-py handled in ansible.module_utils.docker_common
+    pass
+
+
+def get_node_facts(client, name):
+    try:
+        return client.inspect_node(name)
+    except NotFound:
+        return None
+    except APIError as exc:
+        if exc.status_code == 503:
+            client.fail(msg="Cannot inspect node: To inspect node execute module on Swarm Manager")
+        client.fail(msg="Error while reading from Swarm manager: %s" % to_native(exc))
+    except Exception as exc:
+        client.module.fail_json(msg="Error inspecting swarm node: %s" % exc)
+
+
+def main():
+    argument_spec = dict(
+        name=dict(type='str', required=True),
+    )
+
+    client = AnsibleDockerClient(
+        argument_spec=argument_spec,
+        supports_check_mode=True,
+        min_docker_version='1.10.0',
+        min_docker_api_version='1.24',
+    )
+
+    node = get_node_facts(client, client.module.params['name'])
+
+    client.module.exit_json(
+        changed=False,
+        exists=(True if node else False),
+        node_facts=node,
+    )
+
+
+if __name__ == '__main__':
+    main()