Question

This script creates a new XML file with the original data and doesn’t have the updates.

<?php

$dom = new DOMDocument();
$dom->load('communities.xml');

$dom->preserveWhiteSpace = false; 
$dom->formatOutput = true; 

// get document element  

$root   = $dom->documentElement;  

$name     = $dom->createElement("NAME");  
$nameText = $dom->createTextNode("Hobbies");  
$name->appendChild($nameText); 

$community = $dom->createElement('COMMUNITY');
$community->appendChild($name);  
$dom->save('communities.xml');

$tidy_options = array(
                'input-xml'    => true,
                'output-xml'   => true,
                'indent'       => true,
                'wrap'         => false,
        );
$tidy = new tidy();
$tidy->parseFile('communities.xml', $tidy_options);
$tidy->cleanRepair();
echo $tidy;

return;

?>

The permissions are right because the file format is modified and the file is saved with a new date.

Answer 1

It looks like you are missing some append statements, namely:

$root->appendChild($name);
...
$root->appendChild($community);