beanstalk-custom.yaml

Parameters:
  KeyName:
    Type: AWS::EC2::KeyPair::KeyName
    Description: KeyPair to be used with your Beanstalk Environment
  InstanceProfile:
    Type: String
    Description: Instance profile to attach to the Beanstalk environment instance
    Default: aws-elasticbeanstalk-ec2-role
Resources:
  myApplication:
    Type: AWS::ElasticBeanstalk::Application
    Properties: 
      ApplicationName: "SampleAWSElasticBeanstalkApplicationnew"
      Description: "AWS Elastic Beanstalk PHP Sample Application"
  myConfigTemplate: 
    Type: AWS::ElasticBeanstalk::ConfigurationTemplate
    Properties: 
      ApplicationName: 
        Ref: myApplication
      Description: "my sample configuration template"
      SolutionStackName: "64bit Amazon Linux 2018.03 v2.9.3 running PHP 7.3"
      OptionSettings: 
        - Namespace: aws:autoscaling:launchconfiguration
          OptionName: EC2KeyName
          Value: 
            Ref: KeyName
        - Namespace: aws:autoscaling:launchconfiguration
          OptionName: IamInstanceProfile
          Value: 
            Ref: InstanceProfile
  myAppVersion: 
    Type: AWS::ElasticBeanstalk::ApplicationVersion
    Properties: 
      ApplicationName: 
        Ref: myApplication
      Description: "my sample version"
      SourceBundle: 
        S3Bucket: !Sub "elasticbeanstalk-samples-${AWS::Region}"
        S3Key: php-newsample-app.zip
  myEnvironment:
    Type: AWS::ElasticBeanstalk::Environment
    Properties: 
      ApplicationName: 
        Ref: myApplication
      Description: "AWS Elastic Beanstalk Environment running PHP Sample Application"
      TemplateName: !Ref myConfigTemplate 
      SolutionStackName: "64bit Amazon Linux 2018.03 v2.9.3 running PHP 7.3"
  RetrieverFunctionRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: "2012-10-17"
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
            Action: "sts:AssumeRole"
      Policies: 
        - 
          PolicyName: "AllowIAMPassRole"
          PolicyDocument: 
            Version: "2012-10-17"
            Statement: 
              - 
                Effect: "Allow"
                Action: "elasticbeanstalk:*"
                Resource: "*"
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole
  RetrieverFunction:
    DependsOn: myEnvironment
    Type: 'AWS::Lambda::Function'
    Properties:
      Description: Lambda function to upload data to dynamodb
      Handler: index.main
      Role: !GetAtt RetrieverFunctionRole.Arn
      Timeout: 600
      Code:
        ZipFile: |
          import json
          import boto3
          import cfnresponse

          from botocore.exceptions import ClientError

          eb = boto3.client('elasticbeanstalk')

          def main(event, context):

              print("Recieved Event: {}".format(json.dumps(event)))

              application_name = event['ResourceProperties']['ApplicationName']
              environment_name = event['ResourceProperties']['EnvironmentName']
              
              physical_resource_id = "{}|{}|CNAME".format(application_name,environment_name)

              try:
                  if event['RequestType'] == 'Create':

                      print("Recieved Create Event...")
                      print("Retrieving Environment Information for {}".format(environment_name))
                      response = fetch_info(application_name,environment_name)
                      
                      cfnresponse.send(event, context,'SUCCESS', response, physical_resource_id)

                  elif event['RequestType'] == 'Update':

                      print("Recieved Update Event...")
                      print("Update Events are not supported for this resource")
                      response = fetch_info(application_name,environment_name)
                      
                      cfnresponse.send(event, context,'SUCCESS', response, physical_resource_id)
                  
                  elif event['RequestType'] == 'Delete':

                      print("Recieved Delete Event...")
                      print("Delete Events are not supported for this resource")
                      
                      cfnresponse.send(event, context,'SUCCESS', {} , physical_resource_id)
              
              except ClientError as e:

                  if e.response['Error']['Code'] == 'ThrottlingException':
                      count = 3
                      attempts = 0
                      while attempts < count:
                          print("Retrying Function Execution....")
                          time.sleep(random.expovariate(1))
                          main(event,context)
                          attempts += 1
                  else:
                      sendResponse(event,context,"","FAILED",{})

          def fetch_info(app,env):
              
              response = eb.describe_environments(
                  ApplicationName=app,
                  EnvironmentNames=[env]
                )

              data = {
                'CNAME': response['Environments'][0]['CNAME']
              }
              return data
      Runtime: python3.7
  CNAMERetriever:
    Type: Custom::CNAMERetriever
    Properties:
      ServiceToken: !GetAtt RetrieverFunction.Arn
      ApplicationName: !Ref myApplication
      EnvironmentName: !Ref myEnvironment

Outputs:
  BeanstalkEnvironmentCNAME:
    Value: 
      Fn::Join:
        - ""
        - - "http://"
          - !GetAtt CNAMERetriever.CNAME