Add a concern to build hierarchies of groups

3 files changed, 29 insertions, 0 deletions

diff --git a/app/models/concerns/group_hierarchy.rb b/app/models/concerns/group_hierarchy.rb
new file mode 100644
index 00000000000..03864023771
--- /dev/null
+++ b/app/models/concerns/group_hierarchy.rb
@@ -0,0 +1,27 @@
+module GroupHierarchy
+  def hierarchy(hierarchy_base = nil)
+    @hierarchy ||= tree_for_child(self, self, hierarchy_base)
+  end
+
+  def parent
+    if self.is_a?(Project)
+      namespace
+    else
+      super
+    end
+  end
+
+  def tree_for_child(child, tree, hierarchy_base)
+    if child.parent.nil? && hierarchy_base.present?
+      raise ArgumentError.new('specified base is not part of the tree')
+    end
+
+    if child.parent != hierarchy_base
+      tree_for_child(child.parent,
+                     { child.parent => tree },
+                     hierarchy_base)
+    else
+      tree
+    end
+  end
+end
diff --git a/app/models/group.rb b/app/models/group.rb
index e746e4a12c9..848e422e067 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -6,6 +6,7 @@ class Group < Namespace
   include Avatarable
   include Referable
   include SelectForProjectAuthorization
+  include GroupHierarchy
 
   has_many :group_members, -> { where(requested_at: nil) }, dependent: :destroy, as: :source # rubocop:disable Cop/ActiveRecordDependent
   alias_method :members, :group_members
diff --git a/app/models/project.rb b/app/models/project.rb
index 59b5a5b3cd7..c221055f8b4 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -17,6 +17,7 @@ class Project < ActiveRecord::Base
   include ProjectFeaturesCompatibility
   include SelectForProjectAuthorization
   include Routable
+  include GroupHierarchy
 
   extend Gitlab::ConfigHelper
   extend Gitlab::CurrentSettings