UPD: added vpc lookup

py/nextSubnetLambda.py

@@ -2,18 +2,22 @@
 To use this function in lambda, one needs to upload netaddr and this code as a package. here is how
 pip3 install netaddr -t ./
 zip -r ../acrolinxNextSubnet.zip .
-
-The cloudformation call back is to be implemented.
 """
 from netaddr import *
 import boto3
-#import cfnresponse
+import cfnresponse
 import json
+import os
 
 def lambda_handler(event, context):
-    session = boto3.Session(region_name='us-west-2')
+    my_vpc = {
+        'eu-west-1': 'vpc-55a5a930',
+        'us-west-2': 'vpc-7155ca14'
+    }
+    session = boto3.session.Session()
+    my_region = session.region_name
     ec2 = session.resource('ec2')
-    vpc = ec2.Vpc('vpc-7155ca14')
+    vpc = ec2.Vpc(my_vpc[my_region])
     subnets = []
     for subnet in vpc.subnets.all():
         subnets.append(IPNetwork(subnet.cidr_block))
@@ -22,11 +26,13 @@ def lambda_handler(event, context):
     nextSubnet = str(lastSubnet.next())
 
     return {
-       'statusCode': 200,
-       'body': json.dumps(str(lastSubnet.next()))
+       'region': my_region,
+       'body': json.dumps(nextSubnet)
     }
 
 #    response_data = {}
 #    response_data = {"cidr": nextSubnet}
 #    my_data = nextSubnet
 #    cfnresponse.send(event,context,cfnresponse.SUCCESS, response_data, my_data)
+
+