Add backend for tips and enable markdown support

app/controllers/tips_controller.rb

@@ -0,0 +1,62 @@
+class TipsController < ApplicationController
+  include CommonBehavior
+
+  before_action :set_tip, only: MEMBER_ACTIONS
+  before_action :set_file_types, only: %i[create edit new update]
+
+  def authorize!
+    authorize(@tip || @tips)
+  end
+  private :authorize!
+
+  def create
+    @tip = Tip.new(tip_params)
+    authorize!
+    create_and_respond(object: @tip)
+  end
+
+  def destroy
+    destroy_and_respond(object: @tip)
+  end
+
+  def edit
+  end
+
+  def tip_params
+    return unless params[:tip].present?
+
+    params[:tip]
+      .permit(:title, :description, :example, :file_type_id)
+      .each { |_key, value| value.strip! unless value.is_a?(Array) }
+      .merge(user_id: current_user.id, user_type: current_user.class.name)
+  end
+  private :tip_params
+
+  def index
+    @tips = Tip.all.paginate(page: params[:page])
+    authorize!
+  end
+
+  def new
+    @tip = Tip.new
+    authorize!
+  end
+
+  def set_tip
+    @tip = Tip.find(params[:id])
+    authorize!
+  end
+  private :set_tip
+
+  def show
+  end
+
+  def update
+    update_and_respond(object: @tip, params: tip_params)
+  end
+
+  def set_file_types
+    @file_types = FileType.all.order(:name)
+  end
+  private :set_file_types
+end