Add users management to site settings (#126)

app/controllers/users_controller.rb

@@ -0,0 +1,36 @@
+class UsersController < ApplicationController
+  before_action :authenticate_user!, only: [:index, :update]
+
+  def index
+    authorize User
+
+    @users = User
+      .all
+      .order(role: :desc)
+
+    render json: @users
+  end
+
+  def update
+    @user = User.find(params[:id])
+    authorize @user
+
+    @user.assign_attributes user_update_params
+
+    if @user.save
+      render json: @user
+    else
+      render json: {
+        error: @user.errors.full_messages
+      }, status: :unprocessable_entity
+    end
+  end
+
+  private
+
+    def user_update_params
+      params
+        .require(:user)
+        .permit(policy(@user).permitted_attributes_for_update)
+    end
+end