gitlab-org--gitlab-foss/app/controllers/projects/clusters/applications_controller.rb

class Projects::Clusters::ApplicationsController < Projects::ApplicationController
  before_action :cluster
  before_action :application_class, only: [:create]
  before_action :authorize_read_cluster!
  before_action :authorize_create_cluster!, only: [:create]

  def create
    application = @application_class.find_or_create_by!(cluster: @cluster)
    application.update(hostname: params[:hostname]) if application.respond_to?(:hostname)

    Clusters::Applications::ScheduleInstallationService.new(project, current_user).execute(application)

    head :no_content
  rescue StandardError
    head :bad_request
  end

  private

  def cluster
    @cluster ||= project.clusters.find(params[:id]) || render_404
  end

  def application_class
    @application_class ||= Clusters::Cluster::APPLICATIONS[params[:application]] || render_404
  end
end