---
AWSTemplateFormatVersion: 2010-09-09

Description: "This template creates lambda function required to configure 2 ADCs in HA pair across Availability Zones"

Parameters:
  QSS3BucketName:
    AllowedPattern: "^[0-9a-zA-Z]+([0-9a-zA-Z-]*[0-9a-zA-Z])*$"
    ConstraintDescription: >-
      Quick Start bucket name can include numbers, lowercase letters, uppercase
      letters, and hyphens (-). It cannot start or end with a hyphen (-).
    Default: aws-quickstart
    Description: >-
      S3 bucket name for the Quick Start assets. This bucket name can include
      numbers, lowercase letters, uppercase letters, and hyphens (-), but should
      not start or end with a hyphen. You can specify your own bucket if you
      copy all of the assets and submodules into it, if you want to override the
      Quick Start behavior for your specific implementation.
    Type: String
  QSS3KeyPrefix:
    AllowedPattern: "^[0-9a-zA-Z-/]*/$"
    ConstraintDescription: >-
      Quick Start key prefix can include numbers, lowercase letters, uppercase
      letters, hyphens (-), and forward slash (/).
    Default: quickstart-citrix-adc-vpx/
    Description: >-
      [Note] The QSS3KeyPrefix should have to end with forward slash (/).
      S3 key prefix for the Quick Start assets. Quick Start key prefix can
      include numbers, lowercase letters, uppercase letters, hyphens (-), and
      forward slash (/).
    Type: String

Resources:
  LambdaZipsBucket:
    Type: AWS::S3::Bucket
  CopyZips:
    Type: Custom::CopyZips
    Properties:
      ServiceToken: !GetAtt CopyZipsFunction.Arn
      DestBucket: !Ref LambdaZipsBucket
      SourceBucket: !Ref QSS3BucketName
      Prefix: !Ref QSS3KeyPrefix
      Objects:
        - functions/packages/adc/lambda-adc.zip
  CopyZipsRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service: lambda.amazonaws.com
            Action: sts:AssumeRole
      ManagedPolicyArns:
        - !Sub arn:${AWS::Partition}:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole
      Path: /
      Policies:
        - PolicyName: lambda-copier
          PolicyDocument:
            Version: 2012-10-17
            Statement:
              - Effect: Allow
                Action:
                  - s3:GetObject
                Resource:
                  - !Sub "arn:${AWS::Partition}:s3:::${QSS3BucketName}/${QSS3KeyPrefix}*"
              - Effect: Allow
                Action:
                  - s3:PutObject
                  - s3:DeleteObject
                Resource:
                  - !Sub "arn:${AWS::Partition}:s3:::${LambdaZipsBucket}/${QSS3KeyPrefix}*"
        - PolicyName: lambdaupdate
          PolicyDocument:
            Version: 2012-10-17
            Statement:
              - Action:
                  - lambda:UpdateFunctionCode
                Resource: "*"
                Effect: Allow
  CopyZipsFunction:
    Type: AWS::Lambda::Function
    Properties:
      Description: Copies objects from a source S3 bucket to a destination
      Handler: index.handler
      Runtime: python3.7
      Role: !GetAtt CopyZipsRole.Arn
      Timeout: 240
      Code:
        ZipFile: |
          import json
          import logging
          import threading
          import boto3
          import cfnresponse
          def copy_objects(source_bucket, dest_bucket, prefix, objects):
              s3 = boto3.client('s3')
              for o in objects:
                  key = prefix + o
                  copy_source = {
                      'Bucket': source_bucket,
                      'Key': key
                  }
                  print(('copy_source: %s' % copy_source))
                  print(('dest_bucket = %s'%dest_bucket))
                  print(('key = %s' %key))
                  s3.copy_object(CopySource=copy_source, Bucket=dest_bucket,
                        Key=key)
          def delete_objects(bucket, prefix, objects):
              s3 = boto3.client('s3')
              objects = {'Objects': [{'Key': prefix + o} for o in objects]}
              s3.delete_objects(Bucket=bucket, Delete=objects)
          def timeout(event, context):
              logging.error('Execution is about to time out, sending failure response to CloudFormation')
              cfnresponse.send(event, context, cfnresponse.FAILED, {}, None)
          def handler(event, context):
              # make sure we send a failure to CloudFormation if the function
              # is going to timeout
              timer = threading.Timer((context.get_remaining_time_in_millis()
                        / 1000.00) - 0.5, timeout, args=[event, context])
              timer.start()
              print(('Received event: %s' % json.dumps(event)))
              status = cfnresponse.SUCCESS
              try:
                  source_bucket = event['ResourceProperties']['SourceBucket']
                  dest_bucket = event['ResourceProperties']['DestBucket']
                  prefix = event['ResourceProperties']['Prefix']
                  objects = event['ResourceProperties']['Objects']
                  if event['RequestType'] == 'Delete':
                      delete_objects(dest_bucket, prefix, objects)
                  else:
                      copy_objects(source_bucket, dest_bucket, prefix, objects)
              except Exception as e:
                  logging.error('Exception: %s' % e, exc_info=True)
                  status = cfnresponse.FAILED
              finally:
                  timer.cancel()
                  cfnresponse.send(event, context, status, {}, None)

Outputs:
  LambdaZipsBucket:
    Description: Destination S3 bucket where lambda is copied
    Value: !Ref LambdaZipsBucket