Lambda invoke fail

Question

I'm trying to test a Lambda within the console but I get the following error whether or not I run my function or even something as basic as a print statement: "Calling the invoke API action failed with this message: The role defined for the function cannot be assumed by Lambda."

I've read what feels like an infinite number of guides/ tutorials/ stack overflow questions that involve updating trust policies/ permissions/ whatever and nothing appears to have any effect on the response.  The regions match, and everything should have all of the access it needs to perform a simple execution and then some.  I'm also the root user on this personal account, if that's a factor.

This problem has persisted over multiple days and a few attempts starting from scratch, but the end result is always the same error.  Any leads and/or guidance are welcome and appreciated, thank you for your time.

Answer

You have assigned a role to the Lambda function. This role should have a trust policy that looks like this:

```
{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Effect": "Allow",
      "Principal": {
        "Service": "lambda.amazonaws.com"
      },
      "Action": "sts:AssumeRole"
    }
  ]
}
```

Lambda invoke fail

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