If you want to curl the Cloud Run URL when its ingress is setting to 'internal', you can do it from a VM sitting in a VPC network of the same project. If you want to use IAP, you need to use 'internal and Cloud Load balancing' for the ingress. https:...

You may want to keep an eye on this issue: https://github.com/GoogleCloudPlatform/cloud-sql-jdbc-socket-factory/issues/502