def print_instances(state=None, tags=None, filters=None):
"""
Print ec2 instances using ec2.get_instances().
tags/filters parameter requires special formatting because
fabric passes all arguments as strings. The 'quotes' are required
so that the pipe is not parsed by the shell.
tags='Key:Value|Key:Value|...'
Example:
fab print_instances:tags='env:prod|InVPC:True',filters='instance-type:t2.micro|tenancy:default'
"""
def _create_dict(items):
""" builds a dict from command line arg """
item_dict = {}
for i in items.split('|'):
arr = i.split(':')
item_dict[arr[0]] = arr[1]
return item_dict
tag_dict = {}
filter_dict = {}
# setup filter dictionaries
if tags:
tag_dict = _create_dict(tags)
if filters:
filter_dict = _create_dict(filters)
instances = ec2.get_instances(state=state, tags=tag_dict, filters=filter_dict)
# print all matching names and ids
for i in instances:
for tag in i.tags:
if tag['Key'] == 'Name':
print '{0}: {1}'.format(tag['Value'], i.instance_id)
def get_unused_records():
'''returns all records currently unused by ec2 instances
this currently does not handle alias->alias records'''
# create list of all existing EC2 IPs stopped instances don't have IP addresses
instances = ec2.get_instances(state='running')
running_ips = [i.private_ip_address for i in instances]
running_ips += [i.public_ip_address for i in instances if i.public_ip_address]
# create list of IPv4Network objects containing AWS cidr ranges
amazon_json = json.loads(
requests.get('https://ip-ranges.amazonaws.com/ip-ranges.json').text)['prefixes']
networks = ['10.0.0.0/8', '172.16.0.0/12', '192.168.0.0/16']
networks += [net['ip_prefix'] for net in amazon_json]
ranges = [ipaddress.ip_network(net.decode()) for net in networks]
# add 'A' records with unused IP addresses to unused_records
# add alias records to new list to be traversed next
unused_records = []
alias_records = []
for record in get_records():
if record['Type'] == 'A' and record.has_key('ResourceRecords'):
ip_addr = record['ResourceRecords'][0]['Value']
# only add to unused_records if IP is not used by a
# running instance and IP is in an AWS address range
if (ip_addr not in running_ips
and True in [ipaddress.ip_address(ip_addr.decode()) in net for net in ranges]):
unused_records.append(record)
elif record['Type'] == 'CNAME' or record.has_key('AliasTarget'):
alias_records.append(record)
# search for alias records that point at unused A records
unused_names = [rec['Name'] for rec in unused_records]
for record in alias_records:
if (record.has_key('ResourceRecords')
and record['ResourceRecords'][0]['Value'] in unused_names):
unused_records.append(record)
elif record.has_key('AliasTarget') and record['AliasTarget']['DNSName'] in unused_names:
unused_records.append(record)
return unused_records
def resize_dev():
""" resize all dev hosts """
instances = ec2.get_instances(tags={'environment':'dev'})
# dry_run: print out potential changes
# force: reboot running instances
ec2.resize_instances(instances, 'm3.large', dry_run=True, force=True)