Question

I’ve some difficulty in determining any way to update my objects as a group. I have an Alert model which has some alerts for the user. I’d like to provide a way to update them in bulk, as I’ve noticed that I often want to. I just don’t know Rails well enough to know what ‘the Rails way’ would be.

My controller:

class AlertsController < ApplicationController
  def index
    @alerts = Alert.all(show: true)
  end
  def destroy
    alert = Alert.get(params[:id])
    ## I lied, I'm not really deleting things, just hiding them from showing
    alert.update(show: false) if alert 
    respond_to do |format|
      format.js { render :nothing => true }
    end
  end

I’ve been using this code in my *.html.haml view to create the delete link for each individual alert:

  - @alerts.each do |alert|
      %span{ :class => 'description' }=alert.description
      = link_to "Destroy", alert, :confirm => "Are you sure", :method => :delete, :remote => :true

What I want to have is a link on my index page Delete All which I could use to hide(update) all of the alerts. I’ve been attempting this with a destroy_all method for my controller, but I felt like it wasn’t quite the right approach, as I didn’t know how to link to something like that. Thank you for pointing me in the right direction.

Here is the destroy_all method I’d hacked together, for reference.

  def destroy_all
    @alerts.each do |alert|
      alert.update(show: false) if alert
      respond_to do |format|
        format.js {render :nothing => true}
      end
    end
  end

Answer 1

I don’t know how you have routed to this controller but I would probably do something like this:

#routes.rb
resources :alerts do
  delete :remove_all, :on => :collection
end

This will create a route looking like /alerts/remove_all which can only be called through the DELETE protocol. By specifying :collection it tells the routing the this route is not a sub route to one specific Alert so no :id is included.

Then the controller action could probably look something like this:

def remove_all
  Alert.update_all({ show: false }, { show: true })
  respond_to do |format|
    format.js {render :nothing => true}
  end
end

The update_all function will make sure that there is only one database update instead of one for each alert that is to be removed. The first argument is a hash containing the updates and the second argument is a hash with the conditions for which records are to be updated.

And from the view you should be able to link to the action like this:

= link_to "Remove All", remove_all_alerts_path, :confirm => "Are you sure", :method => :delete, :remote => :true

remove_all_alerts_path is a path helper that is automatically generated when you use the above syntax in routes.rb