[SOLVED] AWS cloudformation permission allowing a lambda to invoke another lambda in amplify appsync app

AWS cloudformation permission allowing a lambda to invoke another lambda in amplify appsync app

I keep getting this error no matter what cloudformation template permission I think of trying.

Error invoking another lambda: failed to invoke function arn:aws:lambda:us-east-1::function:: operation error Lambda: Invoke, https response error StatusCode: 403, api error AccessDeniedException: User: arn:aws:sts:::assumed-role// is not authorized to perform: lambda:InvokeFunction on resource: arn:aws:lambda:us-east-1::function: because no identity-based policy allows the lambda:InvokeFunction action

I tried adding this resource based policy to the cloud formation:

"InvokeLambdaFunction": {
  "DependsOn": [
    "LambdaFunction"
  ],
  "Type": "AWS::Lambda::Permission",
  "Properties": {
    "Action": "lambda:InvokeFunction",
    "FunctionName": {
      "Fn::Sub": "FunctionToCall-${env}"
    },
    "Principal": "lambda.amazonaws.com",
    "SourceArn": {
      "Fn::Sub": "arn:aws:lambda:${AWS::Region}:${AWS::AccountId}:function:InvokerFunction-${env}"
    }
  }
}

How is this wrong or what more do I need to do to enable this?

Solution

I just learned that amplify update function added invoke privileges to the relevant lambda for me, so I didn't have to manually mess with the templates at all.