CloudFormation ApiGateway and Lambda with PATH_PART

template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Description: Setup AWS Lambda integrated with ApiGateway
Parameters:
  apiGatewayName:
    Type: String
    Default: test_rest_api
  apiGatewayStageName:
    Type: String
    Default: test
  lambdaFunctionName:
    Type: String
    Default: test_lambda
  
Resources:
  testLambdaIAMRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Action:
              - sts:AssumeRole
            Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
      Policies:
      - PolicyName: lambda
        PolicyDocument:
          Version: 2012-10-17
          Statement:
            - Action:
              - logs:CreateLogGroup
              - logs:CreateLogStream
              - logs:PutLogEvents
              Effect: Allow
              Resource:
                - !Sub arn:aws:logs:${AWS::Region}:${AWS::AccountId}:log-group:/aws/lambda/${lambdaFunctionName}:*

  testLambda:
    Type: AWS::Lambda::Function
    Properties:
      FunctionName: !Ref lambdaFunctionName
      Handler: index.lambda_handler
      MemorySize: 128
      Role: !GetAtt testLambdaIAMRole.Arn
      Runtime: python3.7
      Timeout: 3
      Code:
        ZipFile: |
          import json

          def lambda_handler(event, context):
              print("received this event: %s" % event)

              return {
                "headers": {
                  'Content-Type': "text/plain"
                },
                "statusCode": 200,
                "body": json.dumps(event)
              }

  testLambdaApiGatewayInvoke:
    Type: AWS::Lambda::Permission
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !GetAtt testLambda.Arn
      Principal: apigateway.amazonaws.com
      SourceArn: !Sub arn:aws:execute-api:${AWS::Region}:${AWS::AccountId}:${testRestApi}/*/*/test_api_action

  testRestApi:
    Type: AWS::ApiGateway::RestApi
    Properties:
      EndpointConfiguration:
        Types:
          - EDGE
      Name: !Ref apiGatewayName

  testApiPOSTMethodResource:
    Type: AWS::ApiGateway::Resource
    Properties:
      RestApiId: !Ref testRestApi
      ParentId: !GetAtt testRestApi.RootResourceId
      PathPart: test_api_action
  
  testApiPOSTMethod:
    Type: AWS::ApiGateway::Method
    Properties:
      ResourceId: !Ref testApiPOSTMethodResource
      RestApiId: !Ref testRestApi
      AuthorizationType: NONE
      HttpMethod: POST
      Integration:
        IntegrationHttpMethod: POST
        Type: AWS_PROXY
        Uri: !Sub
          - arn:aws:apigateway:${AWS::Region}:lambda:path/2015-03-31/functions/${lambdaArn}/invocations
          - lambdaArn: !GetAtt testLambda.Arn

  testApiDeployment:
    Type: AWS::ApiGateway::Deployment
    DependsOn:
      - testApiPOSTMethod
    Properties:
      RestApiId: !Ref testRestApi
      StageName: !Ref apiGatewayStageName