Magento 2 admin custom route results in 404 error

Question

I'm beginning with Magento CE 2.1 and I'm stuck with an admin custom route issue that results in a 404 error.

I created a module named 'VM_import' and get it registered (checked).

Now i try to create a custom route :

file : app\code\ [company_name]\VM_import\etc\adminhtml\routes.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:App/etc/routes.xsd">
    <router id="admin">
        <route id="example" frontName="example">
            <module name="VM_import" before="Magento_Backend" />
        </route>
    </router>
</config>

and a dedicated Controller :

file : app\code\ [company_name]\VM_import\Controller\Adminhtml\Index\Index.php

<?php
namespace <company_name>\VM_import\Controller\Adminhtml\Index;
class Index extends \Magento\Backend\App\Action
{
    public function execute()
    {
        echo 'it works !';
        die();
    }
}

Then trying to access to http://[host]/[admin_path]/example results in a 404 error page.

I believe i did something wrong (paths, namespaces, ...) that makes the routing process fail but I cannot figure out what it is or how to efficiently debug it.

Any help would be really appreciated :)

Answer 1

It was only a naming convention issue, I tried to rename my module Vmap_Import instead of VM_import and it worked.

The lower/uppercase construction of the module's name was the only problem, and magento error messages, did not help at all.