API Gateway proxy Lambda loses permissions when functionName is changed

[masse-solita]

Reproduction Steps

1. Create an API Gateway RestAPI and a LambdaIntegration
2. Deploy
3. Change the Lambda's functionName property.
4. Deploy

Error Log

API Gateway fails to invoke the function and reports:
Execution failed due to configuration error: Invalid permissions on Lambda function

Environment

• CLI Version : 1.18.0 (build bc924bc)
• Framework Version: 1.18.0
• OS : Mac OSX
• Language : TypeScript

Other

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This is 🐛 Bug Report

[nija-at]

Ack'ing this issue. Changing the function name in a API Gateway Lambda integration does break the integration.

Repro code -

import lambda = require('@aws-cdk/aws-lambda');
import apig = require('@aws-cdk/aws-apigateway');
import core = require('@aws-cdk/core');

const app = new core.App();
const stack = new core.Stack(app, 'mystack');

const handler = new lambda.Function(stack, 'myfunction', {
    functionName: 'myfunctionname-1',
    code: lambda.Code.fromAsset('resources'),
    runtime: lambda.Runtime.NODEJS_10_X,
    handler: 'index.handler'
});

const restapi = new apig.RestApi(stack, 'myrestapi');

restapi.root.addMethod('ANY', new apig.LambdaIntegration(handler));

[OG84]

Omg spent 2 days figuring out why i get an AuthorizerConfigurationException 500 response.
Until I found this issue 😄