Abstract out project out of ClustersController

To the extent possible swap out `project` with `clusterable`

- Abstract paths for showing cluster or clusters. This will allow us to
swap in alternative paths for group level cluster

- Push :project_id and :namespace_id params from the URL to the POST
body.

- Create a nice helper for to generate links for the destroy
action

For some reason, spec :project_id and :namespace_id param are not going
through `to_param` for a JSON format. Manually call `to_param` to fix
specs.

- Move :layout to BaseController

2 files changed, 32 insertions, 2 deletions

diff --git a/app/controllers/clusters/applications_controller.rb b/app/controllers/clusters/applications_controller.rb
index a5ac5fe3f8e..250f42f3096 100644
--- a/app/controllers/clusters/applications_controller.rb
+++ b/app/controllers/clusters/applications_controller.rb
@@ -19,7 +19,7 @@ class Clusters::ApplicationsController < Clusters::BaseController
   private
 
   def cluster
-    @cluster ||= project.clusters.find(params[:id]) || render_404
+    @cluster ||= clusterable.clusters.find(params[:id]) || render_404
   end
 
   def create_cluster_application_params
diff --git a/app/controllers/clusters/base_controller.rb b/app/controllers/clusters/base_controller.rb
index 2804b236d17..2e9997dfc08 100644
--- a/app/controllers/clusters/base_controller.rb
+++ b/app/controllers/clusters/base_controller.rb
@@ -9,6 +9,10 @@ class Clusters::BaseController < ApplicationController
   before_action :repository, if: :project_type?
   before_action :authorize_read_cluster!
 
+  layout :determine_layout
+
+  helper_method :clusters_page_path, :cluster_page_path, :new_cluster_page_path
+
   private
 
   # We can extend to `#group_type?` in the future
@@ -32,8 +36,34 @@ class Clusters::BaseController < ApplicationController
     access_denied! unless can?(current_user, :create_cluster, clusterable)
   end
 
+  def determine_layout
+    if project_type?
+      'project'
+    end
+  end
+
   def clusterable
-    project if project_type?
+    if project_type?
+      project
+    end
+  end
+
+  def cluster_page_path(cluster)
+    if project_type?
+      project_cluster_path(project, cluster)
+    end
+  end
+
+  def clusters_page_path
+    if project_type?
+      project_clusters_path(project)
+    end
+  end
+
+  def new_cluster_page_path
+    if project_type?
+      new_project_cluster_path(project)
+    end
   end
 
   def project_type?