wikimedia / zest-css
Fast, lightweight, extensible CSS selector engine for PHP
Requires
- php: >=7.2.0
- ext-mbstring: *
- ext-xml: *
Requires (Dev)
- mediawiki/mediawiki-codesniffer: 35.0.0
- mediawiki/mediawiki-phan-config: 0.10.6
- mediawiki/minus-x: 1.1.1
- ockcyp/covers-validator: 1.3.3
- php-parallel-lint/php-console-highlighter: 0.5.0
- php-parallel-lint/php-parallel-lint: 1.2.0
- phpunit/phpunit: ^8.5 || ^9.5
- wikimedia/remex-html: ^2.2.2 || ^2.3
- wikimedia/testing-access-wrapper: ~1.0
Suggests
- ext-intl: *
README
zest.php is a fast, lightweight, extensible CSS selector engine for PHP.
Zest was designed to be very concise while still supporting CSS3/CSS4 selectors and remaining fast.
This is a port to PHP of the zest.js selector library. Since that project hasn't been updated in a while, bugfixes have been taken from the copy of zest included in the domino DOM library.
Report issues on Phabricator.
Usage
use Wikimedia\Zest\Zest; $els = Zest::find('section! > div[title="hello" i] > :local-link /href/ h1', $doc);
Install
This package is available on Packagist:
$ composer require wikimedia/zest-css
API
Zest::find( string $selector, DOMNode $context ): array
This is equivalent to the standard
DOM method ParentNode#querySelectorAll()
.
Zest::matches( DOMNode $element, string $selector ): bool
This is equivalent to the standard
DOM method Element#matches()
.
Since the PHP implementations of
DOMDocument::getElementById
and
DOMDocument#getElementsByTagName
have some performance and spec-compliance issues, Zest also exports useful
performant and correct versions of these:
Zest::getElementsById( DOMNode $contextNode, string $id ): array
This is equivalent to the standard DOM method
Document#getElementById()
(although you can use any context node, not just the top-level document).
Zest::getElementsByTagName( DOMNode $contextNode, string $tagName ): DOMNodeList
This is equivalent to the standard DOM method Element#getElementsByTagName()
.
Extension
It is possible to add your own selectors, operators, or combinators.
These are added to an instance of ZestInst
, so they don't affect other
instances of Zest or the static Zest::find
/Zest::matches
methods.
The ZestInst
class has non-static versions of all the static methods
available on Zest
.
Adding a simple selector
Adding simple selectors is fairly straight forward. Only the addition of pseudo classes and attribute operators is possible. (Adding your own "style" of selector would require changes to the core logic.)
Here is an example of a custom :name
selector which will match for an
element's name
attribute: e.g. h1:name(foo)
. Effectively an alias
for h1[name=foo]
.
use Wikimedia\Zest\ZestInst; $z = new ZestInst; $z->addSelector1( ':name', function( string $param ):callable { return function ( DOMNode $el ) use ( $param ):bool { if ($el->getAttribute('name') === $param) return true; return false; }; } ); // Use it! $z->find( 'h1:name(foo)', $document );
NOTE: if your pseudo-class does not take a parameter, use addSelector0
.
Adding an attribute operator
$z = new ZestInst; // `$attr` is the attribute // `$val` is the value to match $z->addOperator( '!=', function( string $attr, string $val ):bool { return $attr !== $val; } ); // Use it! $z->find( 'h1[name != "foo"]', $document );
Adding a combinator
Adding a combinator is a bit trickier. It may seem confusing at first because the logic is upside-down. Zest interprets selectors from right to left.
Here is an example how a parent combinator could be implemented:
$z = new ZestInst; $z->addCombinator( '<', function( callable $test ): callable { return function( DOMNode $el ) use ( $test ): ?DOMNode { // `$el` is the current element $el = $el->firstChild; while ($el) { // return the relevant element // if it passed the test if ($el->nodeType === 1 && call_user_func($test, $el)) { return $el; } $el = $el->nextSibling; } return null; }; } ); // Use it! $z->find( 'h1 < section', $document );
The $test
function tests whatever simple selectors it needs to look for, but
it isn't important what it does. The most important part is that you return
the relevant element once it's found.
Tests
$ composer test
License and Credits
The original zest codebase is (c) Copyright 2011-2012, Christopher Jeffrey.
The port to PHP was initially done by C. Scott Ananian and is (c) Copyright 2019 Wikimedia Foundation.
Both the original zest codebase and this port are distributed under the MIT license; see LICENSE for more info.