Remove support for creating non-RBAC kubernetes clusters

app/views/clusters/clusters/gcp/_form.html.haml

@@ -65,15 +65,6 @@
       %p.form-text.text-muted
         = s_('ClusterIntegration|Learn more about %{help_link_start_machine_type}machine types%{help_link_end} and %{help_link_start_pricing}pricing%{help_link_end}.').html_safe % { help_link_start_machine_type: help_link_start % { url: machine_type_link_url }, help_link_start_pricing: help_link_start % { url: pricing_link_url }, help_link_end: help_link_end }
 
-    .form-group
-      = provider_gcp_field.check_box :legacy_abac, { label: s_('ClusterIntegration|RBAC-enabled cluster'),
-        label_class: 'label-bold' }, false, true
-      .form-text.text-muted
-        = s_('ClusterIntegration|Enable this setting if using role-based access control (RBAC).')
-        = s_('ClusterIntegration|This option will allow you to install applications on RBAC clusters.')
-        = link_to _('More information'), help_page_path('user/project/clusters/index.md',
-          anchor: 'role-based-access-control-rbac-core-only'), target: '_blank'
-
   .form-group
     = field.check_box :managed, { label: s_('ClusterIntegration|GitLab-managed cluster'),
       label_class: 'label-bold' }

changelogs/unreleased/55902-disable-creation-of-non-rbac-kubernetes-clusters.yml

+---
+title: Remove support for creating non-RBAC kubernetes clusters
+merge_request: 29614
+author:
+type: removed

doc/user/project/clusters/index.md

@@ -71,7 +71,6 @@ new Kubernetes cluster to your project:
    - **Number of nodes** - Enter the number of nodes you wish the cluster to have.
    - **Machine type** - The [machine type](https://cloud.google.com/compute/docs/machine-types)
      of the Virtual Machine instance that the cluster will be based on.
-   - **RBAC-enabled cluster** - Leave this checked if using default GKE creation options, see the [RBAC section](#rbac-cluster-resources) for more information.
    - **GitLab-managed cluster** - Leave this checked if you want GitLab to manage namespaces and service accounts for this cluster. See the [Managed clusters section](#gitlab-managed-clusters) for more information.
 1. Finally, click the **Create Kubernetes cluster** button.
 
@@ -86,6 +85,9 @@ account](#access-controls). Starting from [GitLab
 creation process will explicitly request that basic authentication and
 client certificate is enabled.
 
+NOTE: **Note:**
+Starting from [GitLab 12.1](https://gitlab.com/gitlab-org/gitlab-ce/issues/55902), all GKE clusters created by GitLab are RBAC enabled. Take a look at the [RBAC section](#rbac-cluster-resources) for more information.
+
 ## Adding an existing Kubernetes cluster
 
 To add an existing Kubernetes cluster to your project:

spec/features/projects/clusters/gcp_spec.rb

@@ -79,10 +79,6 @@ describe 'Gcp Cluster', :js do
 
           expect(page).to have_content('Something wrong!')
         end
-
-        it 'user sees RBAC is enabled by default' do
-          expect(page).to have_checked_field('RBAC-enabled cluster')
-        end
       end
 
       context 'when user filled form with invalid parameters' do