feat(inventory): Enable inventory endpoint with env variable

by using an env variable the inventory endpoint can be enabled.

!3 #4

includes/etc/apache2/sites-available/000-default.conf

@@ -2,24 +2,43 @@
   DocumentRoot /var/www/html/public
 
   <Directory /var/www/html/public>
+
     Require all granted
     RewriteEngine On
+
+    # Paths:
+    #  Reference: https://glpi-agent.readthedocs.io/en/latest/configuration.html
+    #  - fusioninventory:                                  /plugins/fusioninventory/
+    #  - Native (non-GlpiInventory plugin):                /front/inventory.php
+    #  - GlpiInventory plugin (Marketplace installed):     /marketplace/glpiinventory/
+    #  - GlpiInventory plugin (plugin folder installed):   /plugins/glpiinventory/
+    #    NOTE: for glpi inventory index.php must be prepended to path so that GUI can still be accessed.
+
     # Don't provide access to inventory on these paths
     # ToDo: add inventory path for /plugins/fusioninventory/
-    RewriteCond %{REQUEST_URI} ^/front/inventory.php$ [OR]
-    RewriteCond %{REQUEST_URI} /plugins/glpiinventory
-    RewriteCond %{REQUEST_URI} !/plugins/glpiinventory/front/ [OR]
-    RewriteCond %{REQUEST_URI} /marketplace/glpiinventory
-    RewriteCond %{REQUEST_URI} !/marketplace/glpiinventory/front/
+
+    RewriteCond %{ENV:GLPI_INVENTORY_PATH} !/front/inventory.php
+      RewriteCond %{REQUEST_URI} ^/front/inventory.php$
+    RewriteRule ^(.*)$ - [R=404,NC]
+
+    RewriteCond %{ENV:GLPI_INVENTORY_PATH} !/plugins/glpiinventory/
+      RewriteCond %{REQUEST_URI} /plugins/glpiinventory
+      RewriteCond %{REQUEST_URI} !/plugins/glpiinventory/front/
+    RewriteRule ^(.*)$ - [R=404,NC]
+
+    RewriteCond %{ENV:GLPI_INVENTORY_PATH} !/marketplace/glpiinventory/
+      RewriteCond %{REQUEST_URI} /marketplace/glpiinventory
+      RewriteCond %{REQUEST_URI} !/marketplace/glpiinventory/front/
     RewriteRule ^(.*)$ - [R=404,NC]
 
 
     RewriteCond %{REQUEST_FILENAME} !-f
-  
     RewriteRule ^(.*)$ index.php [QSA,L]
+
   </Directory>
 
   ErrorLog /var/log/apache2/error-glpi.log
   LogLevel warn
   CustomLog /var/log/apache2/access-glpi.log combined
+
 </VirtualHost>