OAS3, Lambda and method re-use

Hi Kevin,

AWS and Lambda bindings can be configured by using the "x-amazon-apigateway-integration" extensions. "operationId" is only used in the absence of the x-amazon-... extensions.

To bind different operations to the same Lambda function, specify the function name in the "uri" property inside "x-amazon-apigateway-integration". The "uri" value looks like this:

x-amazon-apigateway-integration:
  type: aws
  uri: "arn:aws:apigateway:REGION:lambda:path/2015-03-31/functions/arn:aws:lambda:REGION:ACCOUNT_ID:function:FUNCTION_NAME/invocations"
  ...

Here's an example with two endpoints, /foo and /bar, which are bound to the same Lambda function named "Foo". Make sure to replace the REGION and ACCOUNT_ID with yours. Hope this helps!

swagger: "2.0"
info:
  title: Lambda function binding test
  version: 1.0.0
produces:
- application/json
paths:
  /foo:
    get:
      operationId: foo
      responses:
        200:
          description: OK
      x-amazon-apigateway-integration:
        type: aws
        passthroughBehavior: when_no_match
        httpMethod: POST
        uri: "arn:aws:apigateway:REGION:lambda:path/2015-03-31/functions/arn:aws:lambda:REGION:ACCOUNT_ID:function:Foo/invocations"
        responses:
          default:
            statusCode: 200
        parameters: {}
        requestTemplates: {}
  /bar:
    get:
      operationId: bar
      responses:
        200:
          description: OK
      x-amazon-apigateway-integration:
        type: aws
        passthroughBehavior: when_no_match
        httpMethod: POST
        uri: "arn:aws:apigateway:REGION:lambda:path/2015-03-31/functions/arn:aws:lambda:REGION:ACCOUNT_ID:function:Foo/invocations"
        responses:
          default:
            statusCode: 200
        parameters: {}
        requestTemplates: {}