.. _signals:

Signals in Satchmo
==================

Signals are a very powerful tool available in Django that allows you to decouple
aspects of your application. The `Django Signals Documentation`_, has this summary:
   
    "In a nutshell, signals allow certain senders to notify a set of receivers that some
    signals: action has taken place."

In addition to the built in Django signals, Satchmo has a number of signals. By using these signals, 
you can add very unique customizations to your store without modifying the Satchmo code.

Signal Descriptions
--------------------

satchmo.configuration.signals
+++++++++++++++++++++++++++++

    * configuration_value_changed
        Sent after a value from the configuration application has been updated.

satchmo.shop.signals
++++++++++++++++++++     

    * satchmo_cart_add_complete
        Sent after an item has been successfully added to the cart.
    
    * order_success
        Sent when an order is complete and the balance goes to zero during a save.
    
    * satchmo_cart_changed
        Sent whenever the status of the cart has changed.
    
    * satchmo_cart_item_price_query
        Sent by the pricing system to allow price overrides when displaying line item prices.
    
    * satchmo_search
        Sent by search_view to ask all listeners to add search results.
    
satchmo.contact.signals
+++++++++++++++++++++++

    * satchmo_contact_view
    
    * satchmo_contact_location_changed
    
    * form_save
    
satchmo.newsletter.signals
++++++++++++++++++++++++++

    * newsletter_subscription_updated
    
satchmo.payment.signals
+++++++++++++++++++++++

    * confirm_sanity_check
    
    * payment_form_init
    
    * payment_methods_query
    
    * form_save
    
satchmo.product.signals
+++++++++++++++++++++++

    * index_prerender
    
    * satchmo_price_query
    
    * subtype_order_success
    
    
Example Usage
-------------
   
    Usage::
    
        from satchmo.shop.signals import satchmo_cart_add_complete
        import myviews
        
        satchmo_cart_add_complete.connect(myviews.cart_add_listener, sender=None)


.. _Django Signals Documentation: http://docs.djangoproject.com/en/dev/topics/signals/