php - DOMDocument::validate() problem

Question

I have a big problem with the PHP DOMDocument::validate() who seems to ask the DTD systematically.

It is a big problem when I whant to validate, for example, an XHTML document as explained here.

As w3.org seems to reject all request from a PHP server, it's impossible to validate my document with this method...

Is there any solution for that ?

Thanks by advance

[EDIT] Here is some precisions :

/var/www/test.php :

<?php
$implementation = new DOMImplementation();

$dtd = $implementation->createDocumentType
       (
         'html',                                     // qualifiedName
         '-//W3C//DTD XHTML 1.0 Transitional//EN',   // publicId
         'http://www.w3.org/TR/xhtml1/DTD/xhtml1-'
           .'transitional.dtd'                       // systemId
       );

$document = $implementation->createDocument('', '', $dtd);

$document->validate();

[http://]127.0.0.1/test.php :

Warning: DOMDocument::validate(http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd): failed to open stream: HTTP request failed! HTTP/1.0 403 Forbidden
 in /var/www/test.php on line 14

Warning: DOMDocument::validate(): I/O warning : failed to load external entity "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" in /var/www/test.php on line 14

Warning: DOMDocument::validate(): Could not load the external subset "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" in /var/www/test.php on line 14

Related question :

• How to import XML string in a php DOMDocument ? (solved)

Answer 1

Like pointed out in the comments, there is a Bug/FeatureRequest for DOMDocument::validate to accept the DTD as a string:

• http://bugs.php.net/bug.php?id=48080

You could host the DTD yourself and change the systemId accordingly or you can provide a custom stream context to any loading done through libxml. For instance, providing a UserAgent will get around the W3C's blocking. You could also add proxy this way. See

• libxml_set_streams_context() and
• list of available HTTP context options

Example:

$di = new DOMImplementation;
$dom = $di->createDocument(
    'html',
    'html',
    $di->createDocumentType(
        'html',
        '-//W3C//DTD XHTML 1.0 Transitional//EN',
        'http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd'
    )
);
$opts = array(
    'http' => array(
        'user_agent' => 'PHP libxml agent',
    )
);
$context = stream_context_create($opts);
libxml_set_streams_context($context);

var_dump($dom->validate());

This would output

Warning: DOMDocument::validate(): Element html content does not follow the DTD, expecting (head , body), got  

Warning: DOMDocument::validate(): Element html namespace name for default namespace does not match the DTD 

Warning: DOMDocument::validate(): Value for attribute xmlns of html is different from default "http://www.w3.org/1999/xhtml" 

Warning: DOMDocument::validate(): Value for attribute xmlns of html must be "http://www.w3.org/1999/xhtml" 

bool(false)