Services module, custom endpoint & authentication
In your code
Replace 'file' =&gt; array('type' =&gt; 'inc', 'module' =&gt; 'services', 'name' =&gt; 'resources/drupalsquare'),
with 'file' =&gt; array('type' =&gt; 'inc', 'module' =&gt; 'NAME_OF_YOUR_MODULE', 'name' =&gt; 'resources/drupalsquare'),
It seems you're wrongly defining your INC file.