Understanding admin links

Question

Im try to make a Magento Admin area module but have got stuck with a link issue.

So far I have my required option in the menu bar but my problem comes when I click the link, I get a 404 error, I expected a grid. I am following a tutorial from excellencemagentoblog.

I understand that the action node within the children node of the tree is the link and I have followed my file path to create what I expected would be the correct link, but that failes and I cannot work out why?

My code is

excellence/employee/adminHtml.xml

<config>
<menu><!--action node, URL of admin controller-->
    <employee module="employee">
        <title>Employee</title>
        <sort_order>90</sort_order>
        <children>
            <items module="employee"><!--adds menu item-->
                <title>Manage Employees</title>
                <sort_order>0</sort_order>
                <action>employee/adminhtml_employee</action><!--Link-->
            </items>
        </children>
    </employee>
</menu>
<acl>
    <resources>
        <all>
            <title>Allow Everthing</title>
        </all>
        <admin>
            <children>
                <excellence_employee>
                    <title>Employee Module</title>
                    <sort_order>10</sort_order>
                </excellence_employee>
            </children>
        </admin>
    </resources>
</acl>
<layout>
    <updates>
        <employee>
            <file>employee.xml</file>
        </employee>
    </updates>
</layout>
</config>

Excellence/Employee/controllers/AdminHtml/EmployeeController.php

class Excellence_Employee_Adminhtml_EmployeeController
    extends Mage_Adminhtml_Controller_Action
{
    public function indexAction()
    {
        $this->loadLayout();
        $this->renderLayout();
    }
}

I have tried logging out and back in again, but I still get the 404. What have i do wrong?

When I click the link the address is

http://magentodevtest.local/index.php/employee/adminhtml_employee/index/key/45435404fsd453453

I have added an image of my file structure, looking at the address bar, my understanding of how files are accessed says it should work (i obviously misunderstand something)

===EDIT===

I have cache disabled

My config.xml is as follows

<config>
<modules>
    <Excellence_Employee>
        <version>0.1.0</version>
    </Excellence_Employee>
</modules>
<global>
    <blocks>
        <employee>
            <class>Excellence_Employee_Block</class>
        </employee>
    </blocks>
    <models>
        <employee>
            <class>Excellence_Employee_Model</class>
        </employee>
    </models>
    <helpers>
        <employee>
            <class>Excellence_Employee_Helper</class>
        </employee>
    </helpers>
</global>
</config>

Answer 1

As I suspected you are missing the routers in your config.xml. Add this node under the <global> node:

<admin>
    <routers>
       <employee>
           <use>admin</use>
           <args>
               <module>Excellence_Employee</module>
               <frontName>employee</frontName>
           </args>
       </employee>
    </routers>
</admin>

Or better yet. a more elegant solution is to have your module have the path start with admin like all the admin modules. For this, instead of the code above add this:

<admin>
    <routers>
        <adminhtml>
            <args>
                <modules>
                    <Excellence_Employee before="Mage_Adminhtml">Excellence_Employee_Adminhtml</Excellence_Employee>
                </modules>
            </args>
        </adminhtml>
    </routers>
</admin>

After adding this your module admin url should look like this admin/employee/index.
And you should change the <action> in your menu to

<action>adminhtml/employee</action>

I recommend the second option. It's nicer and has some advantages if you want to use for example Varnish in front of your server. It's easier to configure.

[EDIT]
The first solution does not work anymore, in versions 1.9.2+ and presents a security risk for versions previous to that.