Add pacemaker cluster module for being managable with ansible

lib/ansible/modules/clustering/pacemaker_cluster.py

@@ -0,0 +1,225 @@
+#!/usr/bin/python
+#coding: utf-8 -*-
+
+# (c) 2016, Mathieu Bultel <mbultel@redhat.com>
+#
+# This module is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This software is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this software.  If not, see <http://www.gnu.org/licenses/>.
+
+import time
+from distutils.version import StrictVersion
+
+DOCUMENTATION = '''
+---
+module: pacemaker_cluster
+short_description: Manage a pacemaker cluster
+version_added: "2.3"
+author: "Mathieu Bultel (matbu)"
+description:
+   - This module can manage a pacemaker cluster and nodes from Ansible using
+     the pacemaker cli.
+options:
+    state:
+      description:
+        - Indicate desired state of the cluster
+      choices: ['online', 'offline', 'restart', 'cleanup']
+      required: true
+    node:
+      description:
+        - Specify which node of the cluster you want to manage. None == the
+          cluster status itself, 'all' == check the status of all nodes.
+      required: false
+      default: None
+    timeout:
+      description:
+        - Timeout when the module should considered that the action has failed
+      required: false
+      default: 300
+    force:
+      description:
+        - Force the change of the cluster state
+      required: false
+      default: true
+requirements:
+    - "python >= 2.6"
+'''
+EXAMPLES = '''
+---
+- name: Set cluster Online
+  hosts: localhost
+  gather_facts: no
+  tasks:
+    - name: get cluster state
+      pacemaker_cluster: state=online
+'''
+
+RETURN = '''
+change:
+    description: True if the cluster state has changed
+    type: bool
+out:
+    description: The output of the current state of the cluster. It return a
+                 list of the nodes state.
+    type: string
+    sample: 'out: [["  overcloud-controller-0", " Online"]]}'
+rc:
+    description: exit code of the module
+    type: bool
+'''
+
+_PCS_CLUSTER_DOWN="Error: cluster is not currently running on this node"
+
+def get_cluster_status(module):
+    cmd = "pcs cluster status"
+    rc, out, err = module.run_command(cmd)
+    if out in _PCS_CLUSTER_DOWN:
+        return 'offline'
+    else:
+        return 'online'
+
+def get_node_status(module, node='all'):
+    if node == 'all':
+        cmd = "pcs cluster pcsd-status %s" % node
+    else:
+        cmd = "pcs cluster pcsd-status"
+    rc, out, err = module.run_command(cmd)
+    if rc is 1:
+        module.fail_json(msg="Command execution failed.\nCommand: `%s`\nError: %s" % (cmd, err))
+    status = []
+    for o in out.splitlines():
+        status.append(o.split(':'))
+    return status
+
+def clean_cluster(module, timeout):
+    cmd = "pcs resource cleanup"
+    rc, out, err = module.run_command(cmd)
+    if rc is 1:
+        module.fail_json(msg="Command execution failed.\nCommand: `%s`\nError: %s" % (cmd, err))
+
+def set_cluster(module, state, timeout, force):
+    if state == 'online':
+        cmd = "pcs cluster start"
+    if state == 'offline':
+        cmd = "pcs cluster stop"
+        if force:
+            cmd = "%s --force" % cmd
+    rc, out, err = module.run_command(cmd)
+    if rc is 1:
+        module.fail_json(msg="Command execution failed.\nCommand: `%s`\nError: %s" % (cmd, err))
+
+    t = time.time()
+    ready = False
+    while time.time() < t+timeout:
+        cluster_state = get_cluster_status(module)
+        if cluster_state == state:
+            ready = True
+            break
+    if not ready:
+        module.fail_json(msg="Failed to set the state `%s` on the cluster\n" % (state))
+
+def set_node(module, state, timeout, force, node='all'):
+    # map states
+    if state == 'online':
+        cmd = "pcs cluster start"
+    if state == 'offline':
+        cmd = "pcs cluster stop"
+        if force:
+            cmd = "%s --force" % cmd
+
+    nodes_state = get_node_status(module, node)
+    for node in nodes_state:
+        if node[1].strip().lower() != state:
+            cmd = "%s %s" % (cmd, node[0].strip())
+            rc, out, err = module.run_command(cmd)
+            if rc is 1:
+                module.fail_json(msg="Command execution failed.\nCommand: `%s`\nError: %s" % (cmd, err))
+
+    t = time.time()
+    ready = False
+    while time.time() < t+timeout:
+        nodes_state = get_node_status(module)
+        for node in nodes_state:
+            if node[1].strip().lower() == state:
+                ready = True
+                break
+    if not ready:
+        module.fail_json(msg="Failed to set the state `%s` on the cluster\n" % (state))
+
+def main():
+    argument_spec = dict(
+        state = dict(choices=['online', 'offline', 'restart', 'cleanup']),
+        node  = dict(default=None),
+        timeout=dict(default=300, type='int'),
+        force=dict(default=True, type='bool'),
+    )
+
+    module = AnsibleModule(argument_spec,
+        supports_check_mode=True,
+    )
+    changed = False
+    state = module.params['state']
+    node = module.params['node']
+    force = module.params['force']
+    timeout = module.params['timeout']
+
+    if state in ['online', 'offline']:
+        # Get cluster status
+        if node is None:
+            cluster_state = get_cluster_status(module)
+            if cluster_state == state:
+                module.exit_json(changed=changed,
+                         out=cluster_state)
+            else:
+                set_cluster(module, state, timeout, force)
+                cluster_state = get_cluster_status(module)
+                if cluster_state == state:
+                    module.exit_json(changed=True,
+                         out=cluster_state)
+                else:
+                    module.fail_json(msg="Fail to bring the cluster %s" % state)
+        else:
+            cluster_state = get_node_status(module, node)
+            # Check cluster state
+            for node_state in cluster_state:
+                if node_state[1].strip().lower() == state:
+                    module.exit_json(changed=changed,
+                             out=cluster_state)
+                else:
+                    # Set cluster status if needed
+                    set_cluster(module, state, timeout, force)
+                    cluster_state = get_node_status(module, node)
+                    module.exit_json(changed=True,
+                             out=cluster_state)
+
+    if state in ['restart']:
+        set_cluster(module, 'offline', timeout, force)
+        cluster_state = get_cluster_status(module)
+        if cluster_state == 'offline':
+            set_cluster(module, 'online', timeout, force)
+            cluster_state = get_cluster_status(module)
+            if cluster_state == 'online':
+                module.exit_json(changed=True,
+                     out=cluster_state)
+            else:
+                module.fail_json(msg="Failed during the restart of the cluster, the cluster can't be started")
+        else:
+            module.fail_json(msg="Failed during the restart of the cluster, the cluster can't be stopped")
+
+    if state in ['cleanup']:
+        set_cluster(module, state, timeout, force)
+        module.exit_json(changed=True,
+                 out=cluster_state)
+
+from ansible.module_utils.basic import AnsibleModule
+if __name__ == '__main__':
+    main()