getURL not finding my custom module controller

Question

I am adding in a new mass action for the sales order grid and when I am putting in the url for my action Magento cannot find my controller.

config.xml

<admin>
    <routers>
        <mymodule>
        <use>admin</use>
        <args>
            <module>Namespace_mymodule</module>
            <frontName>frontendname</frontName>
        </args>
        </mymodule>
    </routers>
</admin>

<global>
    <events>
        <adminhtml_block_html_before>
        <observers>
            <mymodule>
            <class>Namespace_mymodule_Model_Observer</class>
            <method>addActions</method>
            </mymodule>
        </observers>
        </adminhtml_block_html_before>
    </events>
</global>

observer.php

public function addActions($event)
{
    $block = $event->getBlock();
    if($block instanceof Mage_Adminhtml_Block_Sales_Order_Grid)
    {
        $block->getMassactionBlock()->addItem('cpsync', array(
            'label' => 'Push Orders to CounterPoint',
            'url' => Mage::helper("adminhtml")->getUrl("frontendname/adminhtml_index/push/")
        ));
    }
}

Whenever I try to use my mass action it sends me to a 404 redirect page with url

sitename.com/index.php/frontendname/adminhtml_index/push/key/

Answer 1

Try the following

if(get_class($block) =='Mage_Adminhtml_Block_Widget_Grid_Massaction'
        && $block->getRequest()->getControllerName() == 'sales/order')
    {
        $block->addItem('cpsync', array(
            'label' => 'Push Orders to CounterPoint',
            'url' => Mage::app()->getStore()->getUrl('*/yourcontroller/youraction'),
        ));
    }

If your controller file's name is something like CpsyncController.php, it would need a method like public function pushAction(){<!--your code here-->}, the */yourcontroller/youraction bit in your Observer would be */cpsync/push

P.S it is imperative that you use the Action suffix after the method name in your controller for the redirect to pick up the function itself.