Document the process for requesting whitelisted IPs on the CUDN
A process has been broadly described for requesting a whitelisted IP allowing Cloud Run to access a resource within the CUDN.
The following issues implement the basic functionality required for this pragmatic approach:
- uis/devops/infra/terraform/gcp-cloud-run-app#19
- https://gitlab.developers.cam.ac.uk/uis/devops/admin/-/issues/226
We should document how this all hangs together to indicate what needs to be completed to allow a developer to deploy a Cloud Run application which has access to a resource in the CUDN.