AWSTemplateFormatVersion: "2010-09-09"

Description: Amazon Transcribe Post Call Analytics - PCA Server - Boto3 Layer Zip

Transform: AWS::Serverless-2016-10-31

Parameters:

  SupportFilesBucketName:
    Type: AWS::SSM::Parameter::Value<String>
    Default: SupportFilesBucketName

  Boto3ZipName:
    Type: String
    Default: transcribeCallAnalyticsModels.zip

Resources:

  boto3ZipFunctionRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: '2012-10-17'
        Statement:
          - Effect: Allow
            Principal:
              Service: lambda.amazonaws.com
            Action: sts:AssumeRole
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole
      Policies:
        - PolicyDocument:
            Version: 2012-10-17
            Statement:
              - Effect: Allow
                Resource: 
                  !Sub
                    - 'arn:aws:s3:::${bucket}*'
                    - bucket: !Ref SupportFilesBucketName
                Action:
                  - 's3:PutObject'
          PolicyName: boto3ZipFunctionS3Policy

  boto3ZipFunction:
    Type: AWS::Lambda::Function
    Properties:
      Handler: index.handler
      Runtime: python3.8
      Role: !GetAtt 'boto3ZipFunctionRole.Arn'
      Timeout: 60
      MemorySize: 512
      Environment:
        Variables:
          SUPPORT_FILES_BUCKET: !Ref SupportFilesBucketName
          BOTO3_ZIP_NAME: !Ref Boto3ZipName
      Code:
        ZipFile: |
          # Package up the Transcribe model version that we need from boto3 (missing from Lambda @ 10/1/2021)
          # This can all be removed on Lambda supports Call Analytics APIs withing its built-in boto3 version
          import os
          import boto3
          import urllib.request
          import tarfile
          from zipfile import ZipFile
          import cfnresponse
          import sys
          import shutil
          import subprocess
          bucket = os.environ['SUPPORT_FILES_BUCKET']
          boto_zip_file_name = os.environ['BOTO3_ZIP_NAME']
          def handler(event, context):
            responseData={}
            status = cfnresponse.SUCCESS
            if event['RequestType'] != 'Delete':
              try:
                # Shift to the tmp folder, as we're writing files
                root_path = '/tmp'
                os.chdir(root_path)
                # Create a folder to hold the boto3 download
                pip_folder = "LocalPipFolder"
                os.mkdir(pip_folder)
                # Create a folder structure to mimic the boto3 model setup for Transcribe
                zip_folder = "models"
                zip_subfolder_1 = "transcribe"
                zip_subfolder_2 = "2017-10-26"
                reqs_file = "requirements.txt"
                zip_folders = [zip_folder,zip_subfolder_1,zip_subfolder_2]
                for folder in zip_folders:
                  root_path = os.path.join(root_path,folder)
                  os.mkdir(root_path)
                # Write out the requirements.txt file, which is the boto3 version we need
                with open(reqs_file, 'w') as f:
                  f.write("boto3==1.24.2")
                  f.close()
                # Install this version of boto3 locally and copy out Transcribe model
                subprocess.check_call([sys.executable, "-m", "pip", "install", "-r", reqs_file, "-t", pip_folder])
                shutil.copy(f"{pip_folder}/botocore/data/{zip_subfolder_1}/{zip_subfolder_2}/service-2.json", "/".join(zip_folders))
                # Zip up the models folder, maintaining the folder structure
                with ZipFile(boto_zip_file_name, 'w') as zipObj:
                   for folderName, subfolders, filenames in os.walk(zip_folder):
                       for filename in filenames:
                           #create complete filepath of file in directory
                           filePath = os.path.join(folderName, filename)
                           # Add file to zip
                           print(f"zipping {filePath}")
                           zipObj.write(filePath)
                # Upload zipfile to S3
                print(f"uploading {boto_zip_file_name} to s3 bucket {bucket}")
                s3_client = boto3.client('s3')
                response = s3_client.upload_file(boto_zip_file_name, bucket, boto_zip_file_name)
              except Exception as e:
                  print(e)
                  responseData["Error"] = f"Exception thrown: {e}"
                  status = cfnresponse.FAILED
            cfnresponse.send(event, context, status, responseData)
      
  boto3Zip:
    Type: Custom::boto3Zip
    Properties:
      ServiceToken: !GetAtt boto3ZipFunction.Arn

  Boto3Layer:
    Type: "AWS::Lambda::LayerVersion"
    DependsOn: boto3Zip
    Properties:
      Content:
        S3Bucket: !Ref SupportFilesBucketName
        S3Key: !Ref Boto3ZipName

Outputs:

  Boto3Layer:
    Description: Lambda layer for Boto3 that other Lambdas may need
    Value: !Ref Boto3Layer