1 files changed, 47 insertions, 0 deletions
diff --git a/app/finders/environment_names_finder.rb b/app/finders/environment_names_finder.rb
new file mode 100644
index 00000000000..a92998921c7
--- /dev/null
+++ b/app/finders/environment_names_finder.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+# Finder for obtaining the unique environment names of a project or group.
+#
+# This finder exists so that the merge requests "environments" filter can be
+# populated with a unique list of environment names. If we retrieve _just_ the
+# environments, duplicates may be present (e.g. multiple projects in a group
+# having a "staging" environment).
+#
+# In addition, this finder only produces unfoldered environments. We do this
+# because when searching for environments we want to exclude review app
+# environments.
+class EnvironmentNamesFinder
+  attr_reader :project_or_group, :current_user
+
+  def initialize(project_or_group, current_user)
+    @project_or_group = project_or_group
+    @current_user = current_user
+  end
+
+  def execute
+    all_environments.unfoldered.order_by_name.pluck_unique_names
+  end
+
+  def all_environments
+    if project_or_group.is_a?(Namespace)
+      namespace_environments
+    else
+      project_environments
+    end
+  end
+
+  def namespace_environments
+    projects =
+      project_or_group.all_projects.public_or_visible_to_user(current_user)
+
+    Environment.for_project(projects)
+  end
+
+  def project_environments
+    if current_user.can?(:read_environment, project_or_group)
+      project_or_group.environments
+    else
+      Environment.none
+    end
+  end
+end