An example CloudFormation Template for Lambda/API Gateway

lambda-api-gateway-cloudformation-example.yaml

Resources:
  AccountsRestApi:
    Type: "AWS::ApiGateway::RestApi"
    Properties:
      Name: "AccountsRestApi"
      FailOnWarnings: "true"
  AccountsResource:
    Type: "AWS::ApiGateway::Resource"
    Properties:
      ParentId:
        Fn::GetAtt:
          - "AccountsRestApi"
          - "RootResourceId"
      PathPart: "accounts"
      RestApiId:
        Ref: AccountsRestApi
  CreateAccountMethod:
    Type: "AWS::ApiGateway::Method"
    Properties:
      HttpMethod: "GET"
      AuthorizationType: "NONE"
      ResourceId:
        Ref: AccountsResource
      RestApiId:
        Ref: AccountsRestApi
      Integration:
        Type: "AWS"
        Uri:
          Fn::Join:
            - ""
            - - "arn:aws:apigateway:"
              - !Ref "AWS::Region"
              - ":lambda:path/"
              - "/2015-03-31/functions/"
              - Fn::GetAtt:
                - CreateAccountLambdaFunction
                - Arn
              - "/invocations"
        IntegrationHttpMethod: "GET"
  CreateAccountLambdaFunction:
    Type: "AWS::Lambda::Function"
    Properties:
      FunctionName: createAccount
      Code:
        S3Bucket: <deployment-bucket>
        S3Key: <lambda-code.zip>
      Handler: endpoints/createAccount/index.handler
      Role: <lambda-role>
      Runtime: nodejs6.10