Allow state=absent for ec2_vol

Add methods to the module to make it more readable and allow reuse

library/cloud/ec2_vol

@@ -55,7 +55,7 @@ options:
     version_added: "1.6"
   id:
     description:
-      - volume id if you wish to attach an existing volume (requires instance)
+      - volume id if you wish to attach an existing volume (requires instance) or remove an existing volume
     required: false
     default: null
     aliases: []
@@ -63,7 +63,7 @@ options:
   volume_size:
     description:
       - size of volume (in GB) to create.
-    required: true
+    required: false
     default: null
     aliases: []
   iops:
@@ -118,7 +118,13 @@ options:
     default: null
     aliases: []
     version_added: "1.6"
-
+  state:
+    description: 
+      - whether to ensure the volume is present or absent
+    required: false
+    default: present
+    choices: ['absent', 'present']
+    version_added: "1.6"
 requirements: [ "boto" ]
 author: Lester Wade
 '''
@@ -173,6 +179,7 @@ EXAMPLES = '''
     wait: yes 
     count: 1
     register: ec2
+
 - local_action: 
     module: ec2_vol 
     instance: "{{ item.id }}" 
@@ -180,6 +187,12 @@ EXAMPLES = '''
     device_name: /dev/xvdf
     with_items: ec2.instances
     register: ec2_vol
+
+# Remove a volume
+- location: action
+    module: ec2_vol
+    id: vol-XXXXXXXX
+    state: absent
 '''
 
 # Note: this module needs to be made idempotent. Possible solution is to use resource tags with the volumes.
@@ -196,57 +209,50 @@ except ImportError:
     print "failed=True msg='boto required for this module'"
     sys.exit(1)
 
-def main():
+def get_volume(module, ec2):
-    argument_spec = ec2_argument_spec()
-    argument_spec.update(dict(
-            instance = dict(),
-            id = dict(),
-            name = dict(),
-            volume_size = dict(),
-            iops = dict(),
-            device_name = dict(),
-            zone = dict(aliases=['availability_zone', 'aws_zone', 'ec2_zone']),
-            snapshot = dict(),
-        )
-    )
-    module = AnsibleModule(argument_spec=argument_spec)
-
-    id = module.params.get('id')
     name = module.params.get('name')
-    instance = module.params.get('instance')
+    id = module.params.get('id')
-    volume_size = module.params.get('volume_size')
-    iops = module.params.get('iops')
-    device_name = module.params.get('device_name')
     zone = module.params.get('zone')
+    filters = {}
+    volume_ids = None
+    if zone:
+        filters['availability_zone'] = zone
+    if name:
+        filters = {'tag:Name': name}
+    if id:
+        volume_ids = [id]
+    try:
+        vols = ec2.get_all_volumes(volume_ids=volume_ids, filters=filters)
+    except boto.exception.BotoServerError, e:
+        module.fail_json(msg = "%s: %s" % (e.error_code, e.error_message))
+
+    if not vols:
+        module.fail_json(msg="Could not find volume in zone (if specified): %s" % name or id)
+    if len(vols) > 1:
+        module.fail_json(msg="Found more than one volume in zone (if specified) with name: %s" % name)
+    return vols[0]
+
+
+def delete_volume(module, ec2):
+    vol = get_volume(module, ec2)
+    if not vol:
+        module.exit_json(changed=False)
+    else:
+       if vol.attachment_state() is not None: 
+           adata = vol.attach_data
+           module.fail_json(msg="Volume %s is attached to an instance %s." % (vol.id, adata.instance_id))
+       ec2.delete_volume(vol.id)
+       module.exit_json(changed=True)
+
+
+def create_volume(module, ec2, zone):
+    name = module.params.get('name')
+    id = module.params.get('id')
+    instance = module.params.get('instance')
+    iops = module.params.get('iops')
+    volume_size = module.params.get('volume_size')
     snapshot = module.params.get('snapshot')
-
-    ec2 = ec2_connect(module)
-
-    if id and name:
-        module.fail_json(msg="Both id and name cannot be specified")
-
-    if not (id or name or volume_size):
-        module.fail_json(msg="Cannot specify volume_size and either one of name or id")
-
-    # Here we need to get the zone info for the instance. This covers situation where 
-    # instance is specified but zone isn't.
-    # Useful for playbooks chaining instance launch with volume create + attach and where the
-    # zone doesn't matter to the user.
-    if instance:
-        reservation = ec2.get_all_instances(instance_ids=instance)
-        inst = reservation[0].instances[0]
-        zone = inst.placement
-
-        # Check if there is a volume already mounted there.
-        if device_name:
-            if device_name in inst.block_device_mapping:
-                module.exit_json(msg="Volume mapping for %s already exists on instance %s" % (device_name, instance),
-                                 volume_id=inst.block_device_mapping[device_name].volume_id,
-                                 device=device_name,
-                                 changed=False)
-
     # If custom iops is defined we use volume_type "io1" rather than the default of "standard"
-
     if iops:
         volume_type = 'io1'
     else:
@@ -259,26 +265,7 @@ def main():
         if iops or volume_size:
             module.fail_json(msg = "Parameters are not compatible: [id or name] and [iops or volume_size]")
 
-        filters = {}
+        volume = get_volume(module, ec2)
-        volume_ids = None
-        if zone:
-            filters['availability_zone'] = zone
-        if name:
-            filters = {'tag:Name': name}
-        if id:
-            volume_ids = [id]
-        try:
-            vols = ec2.get_all_volumes(volume_ids=volume_ids, filters=filters)
-        except boto.exception.BotoServerError, e:
-            module.fail_json(msg = "%s: %s" % (e.error_code, e.error_message))
-
-        if not vols:
-            module.fail_json(msg = "Could not find volume in zone (if specified): %s" % name or id)
-        if len(vols) > 1:
-            module.fail_json(msg =
-               "Found more than one volume in zone (if specified) with name: %s" % name)
-
-        volume = vols.pop()
         if volume.attachment_state() is not None:
             adata = volume.attach_data
             if adata.instance_id != instance:
@@ -298,12 +285,15 @@ def main():
                 volume.update()
         except boto.exception.BotoServerError, e:
             module.fail_json(msg = "%s: %s" % (e.error_code, e.error_message))
+    return volume
 
-    # Attach the created volume.
+
+def attach_volume(module, ec2, volume, instance):
+    device_name = module.params.get('device_name')
 
     if device_name and instance:
         try:
-            attach = volume.attach(inst.id, device_name)
+            attach = volume.attach(instance.id, device_name)
             while volume.attachment_state() != 'attached':
                 time.sleep(3)
                 volume.update()
@@ -334,11 +324,65 @@ def main():
         except boto.exception.BotoServerError, e:
             module.fail_json(msg = "%s: %s" % (e.error_code, e.error_message))
 
-    print json.dumps({
+
-        "volume_id": volume.id,
+def main():
-        "device": device_name
+    argument_spec = ec2_argument_spec()
-    })
+    argument_spec.update(dict(
-    sys.exit(0)
+            instance = dict(),
+            id = dict(),
+            name = dict(),
+            volume_size = dict(),
+            iops = dict(),
+            device_name = dict(),
+            zone = dict(aliases=['availability_zone', 'aws_zone', 'ec2_zone']),
+            snapshot = dict(),
+            state = dict(choices=['absent', 'present'], default='present')
+        )
+    )
+    module = AnsibleModule(argument_spec=argument_spec)
+
+    id = module.params.get('id')
+    name = module.params.get('name')
+    instance = module.params.get('instance')
+    volume_size = module.params.get('volume_size')
+    iops = module.params.get('iops')
+    device_name = module.params.get('device_name')
+    zone = module.params.get('zone')
+    snapshot = module.params.get('snapshot')
+    state = module.params.get('state')
+
+    ec2 = ec2_connect(module)
+
+    if id and name:
+        module.fail_json(msg="Both id and name cannot be specified")
+
+    if not (id or name or volume_size):
+        module.fail_json(msg="Cannot specify volume_size and either one of name or id")
+
+    # Here we need to get the zone info for the instance. This covers situation where 
+    # instance is specified but zone isn't.
+    # Useful for playbooks chaining instance launch with volume create + attach and where the
+    # zone doesn't matter to the user.
+    if instance:
+        reservation = ec2.get_all_instances(instance_ids=instance)
+        inst = reservation[0].instances[0]
+        zone = inst.placement
+
+        # Check if there is a volume already mounted there.
+        if device_name:
+            if device_name in inst.block_device_mapping:
+                module.exit_json(msg="Volume mapping for %s already exists on instance %s" % (device_name, instance),
+                                 volume_id=inst.block_device_mapping[device_name].volume_id,
+                                 device=device_name,
+                                 changed=False)
+
+    if state == 'absent':
+        delete_volume(module, ec2)
+    else:
+        volume = create_volume(module, ec2, zone)
+        if instance:
+            attach_volume(module, ec2, volume, inst)
+        module.exit_json(volume_id=volume.id, device=device_name)
 
 # import module snippets
 from ansible.module_utils.basic import *