Rails Paperclip: update vs. update_attributes

Question

I realized something quite strange when attempting to upload an image via the paperclip gem for my user model (under the avatar attribute). For some reason there User.update and @user.update_attributes behaves differently. Does anyone know why this is so?

#using @user.update_attributes(user_avatar_params) def update_profile_pic     @user = User.find(params[:id])     @user.update_attributes(user_avatar_params)     puts @user.avatar_file_name.nil? # prints false as expected     respond_to do |format|       format.html { redirect_to :back }       format.js     end end  #using User.update(@user.id, user_avatar_params) def update_profile_pic     @user = User.find(params[:id])     User.update(@user.id, user_avatar_params)     puts @user.avatar_file_name.nil? # prints true although successfully saves     respond_to do |format|       format.html { redirect_to :back }       format.js     end end 

And here is my strong params in the user_controller.rb

def user_avatar_params   params.require(:user).permit(:avatar) end 

Answer 1

For what it's worth, as of Rails 4.0.2, #update returns false if the update failed, not simply the object which the update failed for. Of further note, #update_attributes is simply an alias of #update now.

Answer 2

ActiveRecord.update has a behavior that may be throwing you off:

Updates an object (or multiple objects) and saves it to the database, if validations pass. The resulting object is returned whether the object was saved successfully to the database or not. http://apidock.com/rails/ActiveRecord/Base/update/class

However the update_attributes will just return false.

Both of these use Model-level validations and so both should save or not save equally. However, the return values will be different.

As @RoaringStones pointed out, the solution is to use

user = User.update(user.id, user_avatar_params)