Hi there, I’m trying to do Python string interpolation within AWS policies JSON string defined in Pulumi object:

import pulumi_aws as aws

iam_role = aws.iam.Role(
        "my-role",
        name="my-role",
        assume_role_policy="""{
                ...
            }
        """,
        inline_policies=[
            aws.iam.RoleInlinePolicyArgs(
                name=f"my-policy-{stack_name}",
                policy=f"""{
                            "Version": "2012-10-17",
                            "Statement": [
                                {
                                    "Effect": "Allow",
                                    "Action": [
                                        "dynamodb:BatchGetItem",
                                        "dynamodb:GetItem",
                                        "dynamodb:Query",
                                        "dynamodb:Scan",
                                    ],
                                    "Resource": "arn:aws:dynamodb:ap-northeast-1:123456:table/myTablesPrefix-{stack_name}-*"
                                }
                            ]
                        }
                    """
            ),
        ],
    )

...but I get the following error:

SyntaxError: f-string: expressions nested too deeply

However, it does not look like I’m trying to do nested string interpolation: I’m just doing string interpolation in a triple quoted string. Right? So maybe it’s Pulumi is doing some string interpolation on top of it? Any idea on how to solve that?

I think you'll have an easier time with IAM policies using

json.dumps

for what it's worth. Writing a Python map is significantly easier and less fragile.