Merge remote-tracking branch 'origin/main' into release-8.6.0-beta1

Author: jmckenna

en/optimization/environment_variables.txt

@@ -111,6 +111,34 @@ MS_ERRORFILE
    available only after the `MS_ERRORFILE` directive has been parsed.
 
    .. seealso:: :ref:`debugging`
+   
+.. index::
+   pair: Environment variables; MS_INDEX_TEMPLATE_DIRECTORY
+
+MS_INDEX_TEMPLATE_DIRECTORY
+   .. versionadded:: 8.6
+
+   The `MS_INDEX_TEMPLATE_DIRECTORY` environment variable can be set 
+   to activate an index page that lists all mapfiles and related services.
+   The value should point to the folder containing the HTML templates
+   to use.  This variable should be set in the MapServer :ref:`config` file.
+
+   If this variable is not set then the index page is not generated.
+
+   Example CONFIG file contents::
+    
+    ENV
+      #
+      # Index page
+      #
+      MS_INDEX_TEMPLATE_DIRECTORY "/ms4w/share/ogcapi/templates/html-index-bootstrap/"   
+    END
+    
+   and then calls the mapserv CGI should return the index page::
+
+     http://127.0.0.1/cgi-bin/mapserv.exe
+
+   .. seealso:: :ref:`index-page` & :ref:`rfc140`   
 
 .. index::
    pair: Environment variables; MS_MAP_NO_PATH