Resource Based policy statements for Lambda

Question

I have 2 lambda functions.
1. #1 - calling the #2
2. #2 - with function url with IAM permission setup.
3. Created policy statement with #1's execution role arn and action as lambda:InvokeFunctionUrl and attached to #2

But getting a forbidden request by the #2.

Do we need to add extra permissions?. Can someone guide me here?

Answer

If you are calling Lambda function #2 from Lambda function #1, there shouldn't be a reason why you would want to use a Function URL (which would require you to trigger the function via a Sigv4 signed HTTPS request).

Instead, I would suggest updating Lambda function #1 to make an SDK call to invoke the Lambda function #2 directly.

Instead, I would suggest updating Lambda function #1 to [make an SDK call to invoke](https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/lambda/client/invoke.html) the Lambda function #2 directly.

Resource Based policy statements for Lambda

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