Allow selection of existing GKE clusters in Cluster page
We already support connecting to GKE to create a new cluster. Why not allowing to select one of the existing clusters instead?
In the CI/CD > Cluster page, allow selection of existing GKE clusters fetched realtime from GCP.
The flow could be:
- ask for OAuth2 if not already available, to interact with GCP
- fetch the list of GKE clusters user has access to, via GCP APIs
- list the clusters in a dropdown
- user picks up one
- fetch parameters for that cluster, configure it as an existing cluster
Links / references
Kubernetes/GKE integration: https://gitlab.com/gitlab-org/gitlab-ce/issues/35956