Conditionally respond with HTTP redirect for xml_http_request

rubyonrails-talk
1

Hi all,

I have select box in one of my views which lists a few contacts. I also have an option in this select box to add a new contact. There is also an observe_field hook to this select box that Ajax requests further info about the selected contact from the controller and displays it in an adjacent "info" div.

Now, I need to redirect the user to the New Contact page from the controller if the selected value from the select box is "new contact".

This is the controller code I have now .... if request.xml_http_request?   if !@contact.blank?     render :partial => "show", :layout => false   elsif params[:id] == "new contact"     redirect_to new_contact_path   else     render :text => "Please select a contact"   end end

This renders the New Contact page in the "info" div. Whereas, I want the user to be completely redirected to the New Contact page like a HTTP response would. Any thoughts on how I can handle this? Any ideas welcome.. Thanks!

2

Two ways of doing this: either the observe_field thingy has a callback that redirects in the right circumstances or you switch to using render :update (and then use page.redirect_to), In the latter case you have to use render :update for all of these 3 possibilities and you need to change your observe_field invocation to not pass the :update option.

Fred

3

Hi Fred,

Thanks for your response.

render :update Ive got quite a few Ruby conditions and styling going in the js.erb file im using now to display the contact information. And ive got more possibilities than the 3 ive shown above in the controller. So this might not be the right option for me. Right?

observe_field callback This might work for me. Right now, the only callbacks I have on the observe_field are showing and hiding the spinner. I have never written custom callbacks on Rails JS helpers. Could you help me through this?

So im guessing I should be having something like this

<%= observe_field 'contact_id', :frequency => 0.5, :update => 'info', :before => "Element.show('spinner')",     :success => "handle_contact_request(value);", :url => show_contact_path,:method =>:get,     :with => 'contact_id' %>

and in application.js

function handle_contact_request(value){

         Element.hide('spinner');          if value=="new contact"          {                 //how do i redirect to the New Contact page?          }          else          {                //show contact info. But how do I handle the conditions and styling??          } }

Am I getting the basic idea right? If yes, how can I handle the conditional redirecting and the rest in Javascript? Thanks again Fred.

4

Hi Fred,

Thanks for your response.

render :update Ive got quite a few Ruby conditions and styling going in the js.erb file im using now to display the contact information. And ive got more possibilities than the 3 ive shown above in the controller. So this might not be the right option for me. Right?

I'm not sure this would be a problem - seems like a few calls to page.replace_html 'info', :partial => 'blah' would do it in the other cases.

observe_field callback This might work for me. Right now, the only callbacks I have on the observe_field are showing and hiding the spinner. I have never written custom callbacks on Rails JS helpers. Could you help me through this?

So im guessing I should be having something like this

<%= observe_field 'contact_id', :frequency => 0.5, :update => 'info', :before => "Element.show('spinner')", :success => "handle_contact_request(value);", :url => show_contact_path,:method =>:get, :with => 'contact_id' %>

Nearly. your success callback gets 2 thigns: response and responseJSON. responseJSON contains whatever JSON you put in the X- JSON header of your response. You callback can be as simple as

check_for_redirect(json){   if(json && json.redirect)     page.location = json.redirect }

and then pass :success => "check_for_redirect(responseJSON)". All you need to do is to set that header appropriately if you want a redirect to happen.

Fred

5

:slight_smile: You were right. It was easy enough to use render :update and replace_html with :partial to accomplish it.

I am however curious as to how we can do this using JSON. I started reading about JSON for another feature I needed but I realised I dint need JSON for it. I feel it would be a good exercise for me to implement it in tackling this problem. Could you explain a little bit more about the code you have shown me above or point me to where I can find the documentation explaining this? From what I remember, JSON is a format (Object Notation) to represent ActiveRecord objects (in Rails) for JS to handle. But setting the header, responseJSON et all is new to me.

Thanks Fred!

6

I am trying to implement Craig Ambrose's Redbox for some form submissions. Ideally for me, when the user selects "Add contact" a redbox modal window should open with the New Contact form and on submission, the contacts select box on the main page should get updated with the newly added contact. I was looking into invoking Redbox from the controller for this (http://ahref.in/8dc58) but I couldnt quite grasp the discussion there. Can Redbox be brought in here without too much trouble? thanks again for you inputs!