I have deployed an AWS lambda which contains:
import json
import boto3
import cfnresponse
import urllib.request
from botocore.exceptions import ClientError
def lambda_handler(event, context):
...
cfnresponse.send(event, context, status, responseData, "CustomResourcePhysicalID")
I tried to get the values of the cfnresponse in my cloudformations:
Resources:
API:
Type: Custom::API
Version: '1.0'
Properties:
ServiceToken: arn:aws:lambda:eu-west-1:1234567891011:function:getCountry
Outputs:
Status:
Value:
!GetAtt API.Data
Now th cfn is stuck and I got the error:
Unable to import module 'lambda_function': No module named 'cfnresponse'
What am I doing wrong? It seems the way to do it when I check the docs.
Cfnresponse is just available in lambda by default with python 2.7. Probably you are using 3.6.
Did you specify your function's source code in ZipFile? If you specify an actual zip file, that module won't be included.
When you use the ZipFile property to specify your function's source code and that function interacts with an AWS CloudFormation custom resource, you can load the cfn-response module to send responses to those resources. The module contains a send method, which sends a response object to a custom resource by way of an Amazon S3 presigned URL (the ResponseURL).
If you need to use an actual zip file, or this doesn't work for any other reason, you can include the module yourself. Its source code is available in the link you provided. For Python 3 it's:
# Copyright 2016 Amazon Web Services, Inc. or its affiliates. All Rights Reserved.
# This file is licensed to you under the AWS Customer Agreement (the "License").
# You may not use this file except in compliance with the License.
# A copy of the License is located at http://aws.amazon.com/agreement/ .
# This file is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or implied.
# See the License for the specific language governing permissions and limitations under the License.
from botocore.vendored import requests
import json
SUCCESS = "SUCCESS"
FAILED = "FAILED"
def send(event, context, responseStatus, responseData, physicalResourceId=None, noEcho=False):
responseUrl = event['ResponseURL']
print(responseUrl)
responseBody = {}
responseBody['Status'] = responseStatus
responseBody['Reason'] = 'See the details in CloudWatch Log Stream: ' + context.log_stream_name
responseBody['PhysicalResourceId'] = physicalResourceId or context.log_stream_name
responseBody['StackId'] = event['StackId']
responseBody['RequestId'] = event['RequestId']
responseBody['LogicalResourceId'] = event['LogicalResourceId']
responseBody['NoEcho'] = noEcho
responseBody['Data'] = responseData
json_responseBody = json.dumps(responseBody)
print("Response body:\n" + json_responseBody)
headers = {
'content-type' : '',
'content-length' : str(len(json_responseBody))
}
try:
response = requests.put(responseUrl,
data=json_responseBody,
headers=headers)
print("Status code: " + response.reason)
except Exception as e:
print("send(..) failed executing requests.put(..): " + str(e))