gluster_peer: Module to create/dismantle trusted storage pool (#37771)

* gluster_peer: Module to create/dismantle trusted storage pool

* gluster_peer: Module to create/dismantle trusted storage pool

Added __init__.py and added function main() in the module.

* gluster_peer: Module to create/dismantle trusted storage pool

Empty __init__.py was needed. Removed comment from the file.

* gluster_peer: Module to create/dismantle trusted storage pool

Addressed review comments.

* gluster_peer: Module to create/dismantle trusted storage pool

Do version check more sanely, improve parameter handling.

* gluster_peer: Module to create/dismantle trusted storage pool

Use isinstance for type comparison.

* gluster_peer: Module to create/dismantle trusted storage pool

Use type=list for nodes parameter, get rid of literal_eval.

* gluster_peer: Module to create/dismantle trusted storage pool

Add parameter check_mode, had missed this somewhere in between.

* gluster_peer: do not set `force' in case of state=present

* gluster_peer: Fix typo in the documentation

* gluster_peer: make peer probe idempotent

* gluster_peer: Fix a logical error while evaluating booleans

* gluster_peer: set locale to C, pass list to run_command

lib/ansible/modules/storage/glusterfs/gluster_peer.py

@@ -0,0 +1,176 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+#
+# Copyright 2015 Nandaja Varma <nvarma@redhat.com>
+# Copyright 2018 Red Hat, Inc.
+#
+# 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: gluster_peer
+short_description: Attach/Detach peers to/from the cluster
+description:
+  - Create or diminish a GlusterFS trusted storage pool. A set of nodes can be
+    added into an existing trusted storage pool or a new storage pool can be
+    formed. Or, nodes can be removed from an existing trusted storage pool.
+version_added: "2.6"
+author: Sachidananda Urs (@sac)
+options:
+    state:
+       choices: ["present", "absent"]
+       default: "present"
+       description:
+          - Determines whether the nodes should be attached to the pool or
+            removed from the pool. If the state is present, nodes will be
+            attached to the pool. If state is absent, nodes will be detached
+            from the pool.
+       required: true
+    nodes:
+       description:
+          - List of nodes that have to be probed into the pool.
+       required: true
+    force:
+       type: bool
+       default: "false"
+       description:
+          - Applicable only while removing the nodes from the pool. gluster
+            will refuse to detach a node from the pool if any one of the node
+            is down, in such cases force can be used.
+requirements:
+  - GlusterFS > 3.2
+notes:
+  - This module does not support check mode.
+'''
+
+EXAMPLES = '''
+- name: Create a trusted storage pool
+  gluster_peer:
+        state: present
+        nodes:
+             - 10.0.1.5
+             - 10.0.1.10
+
+- name: Delete a node from the trusted storage pool
+  gluster_peer:
+         state: absent
+         nodes:
+              - 10.0.1.10
+
+- name: Delete a node from the trusted storage pool by force
+  gluster_peer:
+         state: absent
+         nodes:
+              - 10.0.0.1
+         force: true
+'''
+
+RETURN = '''
+'''
+
+from ansible.module_utils.basic import AnsibleModule
+from distutils.version import LooseVersion
+
+
+class Peer(object):
+    def __init__(self, module):
+        self.module = module
+        self.state = self.module.params['state']
+        self.nodes = self.module.params['nodes']
+        self.glustercmd = self.module.get_bin_path('gluster', True)
+        self.lang = dict(LANG='C', LC_ALL='C', LC_MESSAGES='C')
+        self.action = ''
+        self.force = ''
+
+    def gluster_peer_ops(self):
+        if not self.nodes:
+            self.module.fail_json(msg="nodes list cannot be empty")
+        self.force = 'force' if self.module.params.get('force') else ''
+        if self.state == 'present':
+            self.nodes = self.get_to_be_probed_hosts(self.nodes)
+            self.action = 'probe'
+            # In case of peer probe, we do not need `force'
+            self.force = ''
+        else:
+            self.action = 'detach'
+        self.call_peer_commands()
+
+    def get_to_be_probed_hosts(self, hosts):
+        peercmd = [self.glustercmd, 'pool', 'list']
+        rc, output, err = self.module.run_command(peercmd,
+                                                  environ_update=self.lang)
+        peers_in_cluster = [line.split('\t')[1].strip() for
+                            line in filter(None, output.split('\n')[1:])]
+        try:
+            peers_in_cluster.remove('localhost')
+        except ValueError:
+            # It is ok not to have localhost in list
+            pass
+        hosts_to_be_probed = [host for host in hosts if host not in
+                              peers_in_cluster]
+        return hosts_to_be_probed
+
+    def call_peer_commands(self):
+        result = {}
+        result['msg'] = ''
+        result['changed'] = False
+
+        for node in self.nodes:
+            peercmd = [self.glustercmd, 'peer', self.action, node]
+            if self.force:
+                peercmd.append(self.force)
+            rc, out, err = self.module.run_command(peercmd,
+                                                   environ_update=self.lang)
+            if rc:
+                result['rc'] = rc
+                result['msg'] = err
+                # Fail early, do not wait for the loop to finish
+                self.module.fail_json(**result)
+            else:
+                if 'already in peer' in out or \
+                   'localhost not needed' in out:
+                    result['changed'] |= False
+                else:
+                    result['changed'] = True
+        self.module.exit_json(**result)
+
+
+def main():
+    module = AnsibleModule(
+        argument_spec=dict(
+            force=dict(type='bool', required=False),
+            nodes=dict(type='list', required=True),
+            state=dict(type='str', choices=['absent', 'present'],
+                       default='present'),
+        ),
+        supports_check_mode=False
+    )
+    pops = Peer(module)
+    required_version = "3.2"
+    # Verify if required GlusterFS version is installed
+    if is_invalid_gluster_version(module, required_version):
+        module.fail_json(msg="GlusterFS version > %s is required" %
+                         required_version)
+    pops.gluster_peer_ops()
+
+
+def is_invalid_gluster_version(module, required_version):
+    cmd = module.get_bin_path('gluster', True) + ' --version'
+    result = module.run_command(cmd)
+    ver_line = result[1].split('\n')[0]
+    version = ver_line.split(' ')[1]
+    # If the installed version is less than 3.2, it is an invalid version
+    # return True
+    return LooseVersion(version) < LooseVersion(required_version)
+
+
+if __name__ == "__main__":
+    main()