Getting EC2 instance information created using cloud formation template - python-2.7

Question

I am creating one EC2 instance using below Cloud Formation template.
Named this template as 'dinesh.json'.
{
"AWSTemplateFormatVersion" : "2010-09-09",
"Description" : "Dinesh template",
"Resources" : {
"MyEC2Instance" : {
"Type" : "AWS::EC2::Instance",
"Properties" : {
"ImageId" : "ami-775e4f16",
"InstanceType" : "t2.micro",
"KeyName" : "****"
}
}
}
}
Now, using boto3 library, I am launching the above template.
import boto3
cft = boto3.client('cloudformation')
create_cft = cft.create_stack(StackName="Dinesh",TemplateURL=r'https://s3-us-west-2.amazonaws.com/dsp-bucket/dinesh.json')
print create_cft
This is running successfully and getting output as below :
{u'StackId': 'arn:aws:cloudformation:us-west-2:089691119308:stack/Dinesh/5b573240-548a-11e6-90a0-50a68a0bca36', 'ResponseMetadata': {'HTTPStatusCode': 200, 'RequestId': '5b507be9-548a-11e6-8405-55192e2be20a', 'HTTPHeaders': {'x-amzn-requestid': '5b507be9-548a-11e6-8405-55192e2be20a', 'date': 'Thu, 28 Jul 2016 06:13:09 GMT', 'content-length': '376', 'content-type': 'text/xml'}}}
Now, I want to get information of above created EC2 instance like public IP, private IP and other info.
So, can any one please suggest me way how to retrieve the information of this specific EC2 instance?
Please let me know the various ways to doing the above thing apart from boto3.

Answer 1

Use the GetAtt function. For example if you have made an ec2 called bob, then adding this to your Output section will show the privateip
"Outputs": {
"AddressOfbob": {
"Description": "Domainame",
"Value": {
"Fn::GetAtt": [
"bob",
"PrivateIp"
]
}
}
}

Answer 2

Thanks #Vorsprung for the pointing towards right direction.
Along with this, I am adding a bit descriptive answer.
Method 1
Getting EC2 instance info when there is "Output" section present in cloud formation template
import boto3
import time
cft = boto3.client('cloudformation')
create_cft = cft.create_stack(StackName="Dinesh-1",TemplateURL=r'https://s3-us-west-2.amazonaws.com/bucket/dinesh.json')
print "Create Stack o/p - ",create_cft
#Just adding sleep so that stack creation come to the status of CREATE_COMPLETE
#More logic can be added to check the status of stack creation programmatically.
time.sleep(120)
des_stack = cft.describe_stacks(StackName="Dinesh-1")
print "Describe Stack o/p - ",des_stack
Output is
Create Stack o/p - {u'StackId': 'arn:aws:cloudformation:us-west-2:089691119308:stack/Dinesh-1/a92318a0-54a7-11e6-b050-50d0184f2', 'ResponseMetadata': {'HTTPStatusCode': 200, 'RequestId': 'a91c023-54a7-11e6-ba43-67cc9d6ed45b', 'HTTPHeaders': {'x-amzn-requestid': 'a91c023-54a7-11e6-ba43-67cc9d6ed45b', 'date': 'Thu, 28 Jul 2016 09:42:55 GMT', 'content-length': '378', 'content-type': 'text/xml'}}}
Describe Stack o/p - {u'Stacks': [{u'StackId': 'arn:aws:cloudformation:us-west-2:089691119308:stack/Dinesh-1/a92318a0-54a7-11e6-b050-50a0184f2', u'Description': 'Dinesh template', u'Tags': [], u'Outputs': [{u'Description': 'Private IP', u'OutputKey': 'PrivateIP', u'OutputValue': '172.3.28.221'}, {u'Description': 'Public IP', u'OutputKey': 'PublicIP', u'OutputValue': '52.5.203.173'}], u'CreationTime': datetime.datetime(2016, 7, 28, 9, 42, 55, 624000, tzinfo=tzutc()), u'StackName': 'Dinesh-1', u'NotificationARNs': [], u'StackStatus': 'CREATE_COMPLETE', u'DisableRollback': False}], 'ResponseMetadata': {'HTTPStatusCode': 200, 'RequestId': 'f19dc8ce-54a7-11e6-83e8-01451bce0ba', 'HTTPHeaders': {'x-amzn-requestid': 'f19dc8ce-54a7-11e6-83e8-01451b7ce0a', 'date': 'Thu, 28 Jul 2016 09:44:57 GMT', 'content-length': '1158', 'content-type': 'text/xml'}}}
In describe_stack output, you will get Public IP and Private IP of created EC2 instance.
Method 2
Getting EC2 instance info when there is no "Output" section present in cloud formation template
import boto3
import time
cft = boto3.client('cloudformation')
create_cft = cft.create_stack(StackName="Dinesh-2",TemplateURL=r'https://s3-us-west-2.amazonaws.com/dsp-bucket/dinesh.json')
print "Create Stack o/p - ",create_cft
#Just adding sleep so that stack creation come to the status of CREATE_COMPLETE
#More logic can be added to check the status of stack creation programmatically.
time.sleep(120)
list_stack_resp = cft.list_stack_resources(StackName="Dinesh-2")
print list_stack_resp
Output is
Create Stack o/p - {u'StackId': 'arn:aws:cloudformation:us-west-2:089691119308:stack/Dinesh-2/7238154a8-11e6-9694-50a686be73f2', 'ResponseMetadata': {'HTTPStatusCode': 200, 'RequestId': '7234f160-54a8-11e6-bda6-ef311cece04b', 'HTTPHeaders': {'x-amzn-requestid': '7234f160-54a8-11e6-bda6-ef311cece04b', 'date': 'Thu, 28 Jul 2016 09:48:32 GMT', 'content-length': '378', 'content-type': 'text/xml'}}}
{'ResponseMetadata': {'HTTPStatusCode': 200, 'RequestId': 'baabaa79-54a8-11e6-90e7-9ba061bfa4c', 'HTTPHeaders': {'x-amzn-requestid': 'baabaa79-54a8-11e6-90e7-9bad061bf4c', 'date': 'Thu, 28 Jul 2016 09:50:33 GMT', 'content-length': '687', 'content-type': 'text/xml'}}, u'StackResourceSummaries': [{u'ResourceType': 'AWS::EC2::Instance', u'PhysicalResourceId': 'i-059f15aa', u'LastUpdatedTimestamp': datetime.datetime(2016, 7, 28, 9, 49, 23, 481000, tzinfo=tzutc()), u'ResourceStatus': 'CREATE_COMPLETE', u'LogicalResourceId': 'MyEC2Instance'}]}
From the output of list_stack_resource, get the 'PhysicalResourceId' which is 'i-059f15aa' in this case.
Then get the output of describe_instance of ec2 to get full info of EC2 instance created above.
import boto3
ec2 = boto3.client('ec2')
ec2_resp = ec2.describe_instances(InstanceIds=['i-059f15aa'])
print ec2_resp
Output is
{u'Reservations': [{u'OwnerId': '089691119308', u'ReservationId': 'r-7245ddb6', u'Groups': [], u'Instances': [{u'Monitoring': {u'State': 'disabled'}, u'PublicDnsName': 'ec2-52-42-17-44.us-west-2.compute.amazonaws.com', u'State': {u'Code': 16, u'Name': 'running'}, u'EbsOptimized': False, u'LaunchTime': datetime.datetime(2016, 7, 28, 9, 48, 37, tzinfo=tzutc()), u'PublicIpAddress': '52.42.10.44', u'PrivateIpAddress': '172.3.29.25', u'ProductCodes': [], u'VpcId': 'vpc-c60a2aa3', u'StateTransitionReason': '', u'InstanceId': 'i-059f15aa', u'ImageId': 'ami-775e4f16', u'PrivateDnsName': 'ip-172-31-29-25.us-west-2.compute.internal', u'KeyName': 'dsp', u'SecurityGroups': [{u'GroupName': 'default', u'GroupId': 'sg-53fdaa37'}], u'ClientToken': 'Dines-MyEC2-DJ1D05Q7A088', u'SubnetId': 'subnet-8d0136e8', u'InstanceType': 't2.micro', u'NetworkInterfaces': [{u'Status': 'in-use', u'MacAddress': '02:9f:ab:4a:3c:0b', u'SourceDestCheck': True, u'VpcId': 'vpc-c60a2aa3', u'Description': '', u'Association': {u'PublicIp': '52.42.170.44', u'PublicDnsName': 'ec2-52-42-170-44.us-west-2.compute.amazonaws.com', u'IpOwnerId': 'amazon'}, u'NetworkInterfaceId': 'eni-d5272ca8', u'PrivateIpAddresses': [{u'PrivateDnsName': 'ip-172-31-29-25.us-west-2.compute.internal', u'Association': {u'PublicIp': '52.42.170.44', u'PublicDnsName': 'ec2-52-42-170-44.us-west-2.compute.amazonaws.com', u'IpOwnerId': 'amazon'}, u'Primary': True, u'PrivateIpAddress': '172.31.29.25'}], u'PrivateDnsName': 'ip-172-31-29-25.us-west-2.compute.internal', u'Attachment': {u'Status': 'attached', u'DeviceIndex': 0, u'DeleteOnTermination': True, u'AttachmentId': 'eni-attach-f33c375f', u'AttachTime': datetime.datetime(2016, 7, 28, 9, 48, 37, tzinfo=tzutc())}, u'Groups': [{u'GroupName': 'default', u'GroupId': 'sg-53fdaa37'}], u'SubnetId': 'subnet-8d0136e8', u'OwnerId': '089691119308', u'PrivateIpAddress': '172.31.29.25'}], u'SourceDestCheck': True, u'Placement': {u'Tenancy': 'default', u'GroupName': '', u'AvailabilityZone': 'us-west-2b'}, u'Hypervisor': 'xen', u'BlockDeviceMappings': [{u'DeviceName': '/dev/sda1', u'Ebs': {u'Status': 'attached', u'DeleteOnTermination': True, u'VolumeId': 'vol-21bddea8', u'AttachTime': datetime.datetime(2016, 7, 28, 9, 48, 37, tzinfo=tzutc())}}], u'Architecture': 'x86_64', u'RootDeviceType': 'ebs', u'RootDeviceName': '/dev/sda1', u'VirtualizationType': 'hvm', u'Tags': [{u'Value': 'arn:aws:cloudformation:us-west-2:089691119308:stack/Dinesh-2/723ba810-54a8-11e6-9694-50a686be73f2', u'Key': 'aws:cloudformation:stack-id'}, {u'Value': 'MyEC2Instance', u'Key': 'aws:cloudformation:logical-id'}, {u'Value': 'Dinesh-2', u'Key': 'aws:cloudformation:stack-name'}], u'AmiLaunchIndex': 0}]}], 'ResponseMetadata': {'HTTPStatusCode': 200, 'RequestId': '8adf8956-0d5a-4d1f-a821-67fec4b5bbf9', 'HTTPHeaders': {'transfer-encoding': 'chunked', 'vary': 'Accept-Encoding', 'server': 'AmazonEC2', 'content-type': 'text/xml;charset=UTF-8', 'date': 'Thu, 28 Jul 2016 09:55:45 GMT'}}}