从控制器调用Model方法

Question

I have a user view where I allow a user to upload his own image or allow him to import image from his LinkedIn profile. My LinkedIn OAuth works fine and returns the url of the image located on linkedin servers. I have a picture_from_url method in my User model which is called by UsersController in it's update method. I set the url to a sessions variable and then send that to the model method in the controller. This ,however, is not updating the image for the user. I have the papertrail gem setup so he can use the image from his computer and change his profile picture just fine.

My Model method

 def  picture_from_url(url)
   encoded_url = URI.encode(url.to_s)
   avatar= URI.parse(encoded_url)
 end

My Controller Call

def update
  @user = User.find(params[:id])
  @user.picture_from_url(session[:linkedin_picture])
  respond_to do |format|
    if can?(current_user, @user)
      if @user.update_attributes(user_params)
        format.html { redirect_to @user, notice: 'User was successfully  updated.' }
        format.json { render_success @user }
      else
        format.html { render action: 'edit' }
        format.json { render_error @user }
      end
    else
      format.html { render action: 'edit', status: :unprocessable_entity }
      format.json { render_error @user }
    end
  end
end

Answer 1

You're not actually saving it (as you said).

You supply your picture_from_url method with a URL, encode and parse it. The last thing you do with it is set it to avatar . I'm guessing that's an attribute on your User model. You're not saving it though.

The following line in your controller doesn't save it either:

@user.update_attributes(user_params)

The above line is updating your @user record with the specified user_params and the URL isn't specified in it.

So, you either have to save your @user record when you call the picture_from_url method like this:

def picture_from_url(url)
  encoded_url = URI.encode(url.to_s)
  update_attributes avatar: URI.parse(encoded_url)
end

Or you can add the formatted URL (which you can retrieve from the picture_from_url method) to the user_params hash which is than saved when update_attributes is called in your controller, like this:

def picture_from_url(url)
  encoded_url = URI.encode(url.to_s)
  URI.parse encoded_url
end

Change the picture_from_url method to the above in your User model (technically you don't have to do this, but it is probably more readable) and your update action to the following:

def update
   @user = User.find(params[:id])
   user_params.merge! avatar: @user.picture_from_url(session[:linkedin_picture])

   ...
 end