Regarding Authorizers on APIs. What is the right way to declare a list of User Pools that can access the API? I see there are ‘Authorizers’ that can be declared in the API props. I’ve been able to use that as the default.authorizer. However that just works for one UserPool. What if I want to declare many user pool authorizers?

You probably need to keep track of a mapping between user and user pool in your app and persist it in your application database. This repo is probably overkill of what you need, but here's an example in a multi-tenant app https://github.com/aws-samples/aws-saas-factory-ref-solution-serverless-saas/blob/main/DOCUMENTATION.md#login-as-an-onboarded-tenant. Here's the authorizer it's referring to https://github.com/aws-samples/aws-saas-factory-ref-solution-serverless-saas/blob/main/server/Resources/tenant_authorizer.py#L43

@Nathan if only a single UserPool can access a route, you can create multiple User Pool JWT authorizers, and specify the one to use at the route level.

Thanks Frank. I was thinking the same thing about the custom authorizer.