kuria/dom

Wrappers around the PHP DOM classes

v3.1.1 2018-05-16 14:19 UTC

This package is auto-updated.

Last update: 2024-10-22 17:55:05 UTC


README

Wrappers around the PHP DOM classes that handle the common DOM extension pitfalls.

https://travis-ci.com/kuria/dom.svg?branch=master

Contents

Features

  • HTML documents
    • encoding sniffing
    • optional tidy support (automatically fix broken HTML)
  • HTML fragments
  • XML documents
  • XML fragments
  • XPath queries
  • creating documents from scratch
  • optional error suppression
  • helper methods for common tasks, such as:
    • querying multiple or a single node
    • checking for containment
    • removing a node
    • removing all nodes from a list
    • prepending a child node
    • inserting a node after another node
    • fetching <head> and <body> elements (HTML)
    • fetching root elements (XML)

Requirements

  • PHP 7.1+

Container methods

These methods are shared by both HTML and XML containers.

Loading documents

<?php

use Kuria\Dom\HtmlDocument; // or XmlDocument, HtmlFragment, etc.

// using loadString()
$dom = new HtmlDocument();
$dom->setLibxmlFlags($customLibxmlFlags); // optional
$dom->setIgnoreErrors($ignoreErrors); // optional
$dom->loadString($html);

// using static loadString() shortcut
$dom = HtmlDocument::fromString($html);

// using existing document instance
$dom = new HtmlDocument();
$dom->loadDocument($document);

// using static loadDocument() shortcut
$dom = HtmlDocument::fromDocument($document);

// creating an empty document
$dom = new HtmlDocument();
$dom->loadEmpty();

Getting or changing document encoding

<?php

// get encoding
$encoding = $dom->getEncoding();

// set encoding
$dom->setEncoding($newEncoding);

Note

The DOM extension uses UTF-8 encoding.

This means that text nodes, attributes, etc.:

  • will be encoded using UTF-8 when read (e.g. $elem->textContent)
  • should be encoded using UTF-8 when written (e.g. $elem->setAttribute())

The encoding configured by setEncoding() is used when saving the document, see Saving documents.

Saving documents

<?php

// entire document
$content = $dom->save();

// single element
$content = $dom->save($elem);

// children of a single element
$content = $dom->save($elem, true);

Getting DOM instances

After a document has been loaded, the DOM instances are available via getters:

<?php

$document = $dom->getDocument();
$xpath = $dom->getXpath();

Running XPath queries

<?php

// get a DOMNodeList
$divs = $dom->query('//div');

// get a single DOMNode (or null)
$div = $dom->query('//div');

// check if a query matches
$divExists = $dom->exists('//div');

Escaping strings

<?php

$escapedString = $dom->escape($string);

DOM manipulation and traversal helpers

Helpers for commonly needed tasks that aren't easily achieved via existing DOM methods:

<?php

// check if the document contains a node
$hasNode = $dom->contains($node);

// check if a node contains another node
$hasNode = $dom->contains($node, $parentNode);

// remove a node
$dom->remove($node);

// remove a list of nodes
$dom->removeAll($nodes);

// prepend a child node
$dom->prependChild($newNode, $existingNode);

// insert a node after another node
$dom->insertAfter($newNode, $existingNode);

Usage examples

HTML documents

Loading an existing document

<?php

use Kuria\Dom\HtmlDocument;

$html = <<<HTML
<!doctype html>
<html>
    <head>
        <meta charset="UTF-8">
        <title>Example document</title>
    </head>
    <body>
        <h1>Hello world!</h1>
    </body>
</html>
HTML;

$dom = HtmlDocument::fromString($html);

var_dump($dom->queryOne('//title')->textContent);
var_dump($dom->queryOne('//h1')->textContent);

Output:

string(16) "Example document"
string(12) "Hello world!"

Optionally, the markup can be fixed by Tidy prior to being loaded.

<?php

$dom = new HtmlDocument();
$dom->setTidyEnabled(true);
$dom->loadString($html);

Note

HTML documents ignore errors by default, so there is no need to call $dom->setIgnoreErrors(true).

Creating an new document

<?php

use Kuria\Dom\HtmlDocument;

// initialize empty document
$dom = new HtmlDocument();
$dom->loadEmpty(['formatOutput' => true]);

// add <title>
$title = $dom->getDocument()->createElement('title');
$title->textContent = 'Lorem ipsum';

$dom->getHead()->appendChild($title);

// save
echo $dom->save();

Output:

<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Lorem ipsum</title>
</head>
<body>
    </body>
</html>

HTML fragments

Loading an existing fragment

<?php

use Kuria\Dom\HtmlFragment;

$dom = HtmlFragment::fromString('<div id="test"><span>Hello</span></div>');

$element = $dom->queryOne('/div[@id="test"]/span');

if ($element) {
    var_dump($element->textContent);
}

Output:

string(5) "Hello"

Note

HTML fragments ignore errors by default, so there is no need to call $dom->setIgnoreErrors(true).

Creating a new fragment

<?php

use Kuria\Dom\HtmlFragment;

// initialize empty fragment
$dom = new HtmlFragment();
$dom->loadEmpty(['formatOutput' => true]);

// add <a>
$link = $dom->getDocument()->createElement('a');
$link->setAttribute('href', 'http://example.com/');
$link->textContent = 'example';

$dom->getBody()->appendChild($link);

// save
echo $dom->save();

Output:

<a href="http://example.com/">example</a>

XML documents

Loading an existing document

<?php

use Kuria\Dom\XmlDocument;

$xml = <<<XML
<?xml version="1.0" encoding="utf-8"?>
<library>
    <book name="Don Quixote" author="Miguel de Cervantes" />
    <book name="Hamlet" author="William Shakespeare" />
    <book name="Alice's Adventures in Wonderland" author="Lewis Carroll" />
</library>
XML;

$dom = XmlDocument::fromString($xml);

foreach ($dom->query('/library/book') as $book) {
   /** @var \DOMElement $book */
   var_dump("{$book->getAttribute('name')} by {$book->getAttribute('author')}");
}

Output:

string(34) "Don Quixote by Miguel de Cervantes"
string(29) "Hamlet by William Shakespeare"
string(49) "Alice's Adventures in Wonderland by Lewis Carroll"

Creating a new document

<?php

use Kuria\Dom\XmlDocument;

// initialize empty document
$dom = new XmlDocument();
$dom->loadEmpty(['formatOutput' => true]);

// add <users>
$document = $dom->getDocument();
$document->appendChild($document->createElement('users'));

// add some users
$bob = $document->createElement('user');
$bob->setAttribute('username', 'bob');
$bob->setAttribute('access-token', '123456');

$john = $document->createElement('user');
$john->setAttribute('username', 'john');
$john->setAttribute('access-token', 'foobar');

$dom->getRoot()->appendChild($bob);
$dom->getRoot()->appendChild($john);

// save
echo $dom->save();

Output:

<?xml version="1.0" encoding="UTF-8"?>
<users>
  <user username="bob" access-token="123456"/>
  <user username="john" access-token="foobar"/>
</users>

Handling XML namespaces in XPath queries

<?php

use Kuria\Dom\XmlDocument;

$xml = <<<XML
<?xml version="1.0" encoding="UTF-8"?>
<lib:root xmlns:lib="http://example.com/">
    <lib:book name="Don Quixote" author="Miguel de Cervantes" />
    <lib:book name="Hamlet" author="William Shakespeare" />
    <lib:book name="Alice's Adventures in Wonderland" author="Lewis Carroll" />
</lib:root>
XML;

$dom = XmlDocument::fromString($xml);

// register namespace in XPath
$dom->getXpath()->registerNamespace('lib', 'http://example.com/');

// query using the prefix
foreach ($dom->query('//lib:book') as $book) {
    /** @var \DOMElement $book */
    var_dump($book->getAttribute('name'));
}

Output:

string(11) "Don Quixote"
string(6) "Hamlet"
string(32) "Alice's Adventures in Wonderland"

XML fragments

Loading an existing fragment

<?php

use Kuria\Dom\XmlFragment;

$dom = XmlFragment::fromString('<fruits><fruit name="Apple" /><fruit name="Banana" /></fruits>');

foreach ($dom->query('/fruits/fruit') as $fruit) {
    /** @var \DOMElement $fruit */
    var_dump($fruit->getAttribute('name'));
}

Output:

string(5) "Apple"
string(6) "Banana"

Creating a new fragment

<?php

use Kuria\Dom\XmlFragment;

// initialize empty fragment
$dom = new XmlFragment();
$dom->loadEmpty(['formatOutput' => true]);

// add a new element
$person = $dom->getDocument()->createElement('person');
$person->setAttribute('name', 'John Smith');

$dom->getRoot()->appendChild($person);

// save
echo $dom->save();

Output:

<person name="John Smith"/>