Add new ec2_vpc_dhcp_options module

This module manages EC2 DHCP options for a given VPC. It allows you to
specify all the options which AWS allows you to set in a DHCP option
set.

lib/ansible/modules/extras/cloud/amazon/ec2_vpc_dhcp_options.py

@@ -0,0 +1,236 @@
+#!/usr/bin/python
+
+# Ansible 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.
+#
+# Ansible 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 Ansible.  If not, see <http://www.gnu.org/licenses/>.
+
+DOCUMENTATION = """
+---
+module: ec2_vpc_dhcp_options
+short_description: Ensures the DHCP options for the given VPC match what's
+  requested
+description:
+  - Converges the DHCP option set for the given VPC to the variables requested.
+      If any of the optional values are missing, they will either be treated
+      as a no-op (i.e., inherit what already exists for the VPC) or a purge of
+      existing options. Most of the options should be self-explanatory.
+author: "Joel Thompson (@joelthompson)"
+version_added: 2.1
+options:
+  - domain_name:
+      description:
+        - The domain name to set in the DHCP option sets
+      required:
+        - false
+      default: ""
+  - dns_servers:
+      description:
+        - A list of hosts to set the DNS servers for the VPC to. (Should be a
+          list of IP addresses rather than host names.)
+      required: false
+      default: []
+  - ntp_servers:
+      description:
+        - List of hosts to advertise as NTP servers for the VPC.
+      required: false
+      default: []
+  - netbios_name_servers:
+      description:
+        - List of hosts to advertise as NetBIOS servers.
+      required: false
+      default: []
+  - netbios_node_type:
+      description:
+        - NetBIOS node type to advertise in the DHCP options. The
+          default is 2, per AWS recommendation
+          http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_DHCP_Options.html
+      required: false
+      default: 2
+  - vpc_id:
+      description:
+        - VPC ID to associate with the requested DHCP option set
+      required: true
+  - delete_old:
+      description:
+        - Whether to delete the old VPC DHCP option set when creating a new one.
+          This is primarily useful for debugging/development purposes when you
+          want to quickly roll back to the old option set. Note that this setting
+          will be ignored, and the old DHCP option set will be preserved, if it
+          is in use by any other VPC. (Otherwise, AWS will return an error.)
+      required: false
+      default: true
+  - inherit_existing:
+      description:
+        - For any DHCP options not specified in these parameters, whether to
+          inherit them from the options set already applied to vpc_id, or to
+          reset them to be empty.
+      required: false
+      default: false
+extends_documentation_fragment: aws
+requirements:
+    - boto
+"""
+
+RETURN = """
+new_options:
+  description: The new DHCP options associated with your VPC
+  returned: changed
+  type: dict
+  sample:
+    domain-name-servers:
+      - 10.0.0.1
+      - 10.0.1.1
+    netbois-name-servers:
+      - 10.0.0.1
+      - 10.0.1.1
+    ntp-servers: None
+    netbios-node-type: 2
+    domain-name: "my.example.com"
+"""
+
+EXAMPLES = """
+# Completely overrides the VPC DHCP options associated with VPC vpc-123456 and deletes any existing
+# DHCP option set that may have been attached to that VPC.
+- ec2_vpc_dhcp_options:
+    domain_name: "foo.example.com"
+    region: us-east-1
+    dns_servers:
+        - 10.0.0.1
+        - 10.0.1.1
+    ntp_servers:
+        - 10.0.0.2
+        - 10.0.1.2
+    netbios_name_servers:
+        - 10.0.0.1
+        - 10.0.1.1
+    netbios_node_type: 2
+    vpc_id: vpc-123456
+    delete_old: True
+    inherit_existing: False
+
+
+# Ensure the DHCP option set for the VPC has 10.0.0.4 and 10.0.1.4 as the specified DNS servers, but
+# keep any other existing settings. Also, keep the old DHCP option set around.
+- ec2_vpc_dhcp_options:
+    region: us-east-1
+    dns_servers:
+      - "{{groups['dns-primary']}}"
+      - "{{groups['dns-secondary']}}"
+    vpc_id: vpc-123456
+    inherit_existing: True
+    delete_old: False
+"""
+
+import boto.vpc
+import socket
+import collections
+
+def _get_associated_dhcp_options(vpc_id, vpc_connection):
+    """
+    Returns the DHCP options object currently associated with the requested VPC ID using the VPC
+    connection variable.
+    """
+    vpcs = vpc_connection.get_all_vpcs(vpc_ids=[vpc_id])
+    if len(vpcs) != 1:
+      return None
+    dhcp_options = vpc_connection.get_all_dhcp_options(dhcp_options_ids=[vpcs[0].dhcp_options_id])
+    if len(dhcp_options) != 1:
+      return None
+    return dhcp_options[0]
+
+
+def _get_vpcs_by_dhcp_options(dhcp_options_id, vpc_connection):
+    return vpc_connection.get_all_vpcs(filters={'dhcpOptionsId': dhcp_options_id})
+
+
+def _get_updated_option(requested, existing, inherit):
+    if inherit and (not requested or requested == ['']):
+        return existing
+    else:
+        return requested
+
+
+def main():
+    argument_spec = ec2_argument_spec()
+    argument_spec.update(dict(
+        domain_name=dict(type='str', default=''),
+        dns_servers=dict(type='list', default=[]),
+        ntp_servers=dict(type='list', default=[]),
+        netbios_name_servers=dict(type='list', default=[]),
+        netbios_node_type=dict(type='int', default=2),
+        vpc_id=dict(type='str', required=True),
+        delete_old=dict(type='bool', default=True),
+        inherit_existing=dict(type='bool', default=False)
+        )
+    )
+
+    module = AnsibleModule(argument_spec=argument_spec, supports_check_mode=True)
+    params = module.params
+
+  
+    region, ec2_url, boto_params = get_aws_connection_info(module)
+    connection = connect_to_aws(boto.vpc, region, **boto_params)
+  
+    inherit_existing = params['inherit_existing']
+  
+    existing_options = _get_associated_dhcp_options(params['vpc_id'], connection)
+    new_options = collections.defaultdict(lambda: None)
+  
+    new_options['domain-name-servers'] = _get_updated_option( params['dns_servers'],
+            existing_options.options.get('domain-name-servers'), inherit_existing)
+  
+    new_options['netbios-name-servers'] = _get_updated_option(params['netbios_name_servers'],
+            existing_options.options.get('netbios-name-servers'), inherit_existing)
+  
+  
+    new_options['ntp-servers'] = _get_updated_option(params['ntp_servers'],
+            existing_options.options.get('ntp-servers'), inherit_existing)
+  
+    # HACK: Why do I make the next two lists? The boto api returns a list if present, so
+    # I need this to properly compare so == works.
+  
+    # HACK: netbios-node-type is an int, but boto returns a string. So, asking for an int from Ansible
+    # for data validation, but still need to cast it to a string
+    new_options['netbios-node-type'] = _get_updated_option(
+            [str(params['netbios_node_type'])], existing_options.options.get('netbios-node-type'),
+            inherit_existing)
+  
+    new_options['domain-name'] = _get_updated_option(
+            [params['domain_name']], existing_options.options.get('domain-name'), inherit_existing)
+  
+    if existing_options and new_options == existing_options.options:
+        module.exit_json(changed=False)
+  
+    if new_options['netbios-node-type']:
+        new_options['netbios-node-type'] = new_options['netbios-node-type'][0]
+  
+    if new_options['domain-name']:
+        new_options['domain-name'] = new_options['domain-name'][0]
+  
+    if not module.check_mode:
+        dhcp_option = connection.create_dhcp_options(new_options['domain-name'],
+                new_options['domain-name-servers'], new_options['ntp-servers'],
+                new_options['netbios-name-servers'], new_options['netbios-node-type'])
+        connection.associate_dhcp_options(dhcp_option.id, params['vpc_id'])
+        if params['delete_old'] and existing_options:
+            other_vpcs = _get_vpcs_by_dhcp_options(existing_options.id, connection)
+            if len(other_vpcs) == 0 or (len(other_vpcs) == 1 and other_vpcs[0].id == params['vpc_id']):
+                connection.delete_dhcp_options(existing_options.id)
+  
+    module.exit_json(changed=True, new_options=new_options)
+  
+
+from ansible.module_utils.basic import *
+from ansible.module_utils.ec2 import *
+
+if __name__ == "__main__":
+    main()