Isocontent

Isocontent is a PHP library that transforms rich‑text content (such as HTML) into a platform‑agnostic Abstract Syntax Tree (AST). The AST can then be rendered back to any target format — HTML, JSON, React Native, mobile views, or anything else you need.

Typical use‑case: accept content from a WYSIWYG editor, store it as a portable AST, and render it on any platform.

Installation

Requires PHP >= 8.2. The DOMParser needs ext-dom and ext-libxml; the JSONRenderer needs ext-json.

composer require unzeroun/isocontent

End‑to‑End Demo

The Isocontent service is the main entry point. Register parsers and renderers, then parse and render content in any supported format:

use Isocontent\Isocontent;
use Isocontent\Parser\DOMParser;
use Isocontent\Renderer\HTMLRenderer;
use Isocontent\Renderer\JSONRenderer;

$isocontent = new Isocontent(
    parsers:   [new DOMParser()],
    renderers: [new HTMLRenderer(), new JSONRenderer()],
);

// 1. Parse HTML into an AST
$ast = $isocontent->buildAST(
    '<h1>Hello</h1><p>This is <strong>rich</strong> content with a <a href="https://example.com">link</a>.</p>',
    'html',
);

// 2. Inspect the AST as a portable array (suitable for JSON storage / API responses)
$ast->toArray();
// [
//     [
//         'type'       => 'block',
//         'block_type' => 'title',
//         'arguments'  => ['level' => 1],
//         'children'   => [
//             ['type' => 'text', 'value' => 'Hello'],
//         ],
//     ],
//     [
//         'type'       => 'block',
//         'block_type' => 'paragraph',
//         'arguments'  => [],
//         'children'   => [
//             ['type' => 'text', 'value' => 'This is '],
//             [
//                 'type'       => 'block',
//                 'block_type' => 'strong',
//                 'arguments'  => [],
//                 'children'   => [
//                     ['type' => 'text', 'value' => 'rich'],
//                 ],
//             ],
//             ['type' => 'text', 'value' => ' content with a '],
//             [
//                 'type'       => 'block',
//                 'block_type' => 'link',
//                 'arguments'  => ['href' => 'https://example.com'],
//                 'children'   => [
//                     ['type' => 'text', 'value' => 'link'],
//                 ],
//             ],
//             ['type' => 'text', 'value' => '.'],
//         ],
//     ],
// ]

// 3. Render back to HTML
$isocontent->render($ast, 'html');
// '<h1>Hello</h1><p>This is <strong>rich</strong> content with a <a>link</a>.</p>'

// 4. Render to JSON
$isocontent->render($ast, 'json');
// The same array structure above, encoded as a JSON string

Core Concepts

Isocontent models content as a tree of nodes:

Class	Description
TextNode	Leaf node holding a plain text value.
BlockNode	Structural element (paragraph, heading, link…) with optional children and typed arguments.
NodeList	Ordered collection of nodes — this is what parsers produce and renderers consume.

Block Types

The DOMParser maps HTML elements to the following block types:

Block Type	HTML Tag(s)	Arguments
paragraph	<p>	—
title	<h1>–<h6>	level (int 1–6)
strong	<strong>	—
emphasis	<em>	—
inline_text	<span>	—
link	<a>	href (string)
list	<ul>, <ol>	ordered (bool)
list_item	<li>	—
quote	<blockquote>	—
new_line	<br>	—
stripped	<del>	—
separator	<hr>	—
subscript	<sub>	—
superscript	<sup>	—
code	<code>	—
generic	any other element	—

Parsers

A parser reads input in a given format and builds an AST through the Builder.

• DOMParser — parses HTML strings via PHP's DOMDocument (format: html)
• ArrayParser — re‑hydrates an AST from a PHP array or decoded JSON (format: array)

Custom Parser

Implement the Parser interface:

use Isocontent\AST\Builder;
use Isocontent\Parser\Parser;

final class MarkdownParser implements Parser
{
    public function supportsFormat(string $format): bool
    {
        return 'markdown' === $format;
    }

    public function parse(Builder $builder, mixed $input): void
    {
        // Build the AST using $builder->addTextNode() / $builder->addBlockNode()
    }
}

Renderers

A renderer converts a NodeList into an output format.

• HTMLRenderer — renders to HTML (format: html). Tag mapping is customizable.
• JSONRenderer — renders to a JSON string (format: json).
• TextDebugRenderer — renders an indented tree for debugging (format: text_debug).

Custom Renderer

Implement the Renderer interface:

use Isocontent\AST\NodeList;
use Isocontent\Renderer\Renderer;

final class ReactNativeRenderer implements Renderer
{
    public function supportsFormat(string $format): bool
    {
        return 'react_native' === $format;
    }

    public function render(NodeList $ast): mixed
    {
        // Walk the AST and produce your output
    }
}

Custom HTML Tag Mapping

The HTMLRenderer uses the Specification pattern to map block types to HTML tags. You can pass your own mapping to override the defaults:

use Isocontent\Renderer\HTMLRenderer;
use Isocontent\Specs\BlockTypeMatch;
use Isocontent\Specs\BlockArgumentMatch;

$renderer = new HTMLRenderer([
    [(new BlockTypeMatch('title'))->and(new BlockArgumentMatch('level', 1)), 'h1'],
    [(new BlockTypeMatch('title'))->and(new BlockArgumentMatch('level', 2)), 'h2'],
    [new BlockTypeMatch('paragraph'), 'p'],
    [new BlockTypeMatch('strong'), 'b'],        // <b> instead of <strong>
    [new BlockTypeMatch('emphasis'), 'i'],       // <i> instead of <em>
    [new BlockTypeMatch('inline_text'), 'font'], // <font> instead of <span>
]);

Available specifications: BlockTypeMatch (match by type), BlockArgumentMatch (match by argument key/value), and AllMatch (compose with ->and()).

Symfony Integration

Register the bundle:

// config/bundles.php
return [
    // ...
    Isocontent\Bridge\Symfony\Bundle\IsocontentBundle::class => ['all' => true],
];

The bundle auto‑discovers all Parser and Renderer implementations (tagged isocontent.parser / isocontent.renderer) and registers a public Isocontent service. All built‑in parsers and renderers are autowired out of the box.

use Isocontent\Isocontent;

final class ContentController
{
    public function __construct(private readonly Isocontent $isocontent) {}

    public function show(): Response
    {
        $ast  = $this->isocontent->buildAST($html, 'html');
        $json = $this->isocontent->render($ast, 'json');
        // ...
    }
}

Two Symfony Form data transformers are also provided: ASTToStringTransformer (Node|NodeList ↔ rendered string) and ASTToArrayTransformer (Node|NodeList ↔ PHP array).

Twig Integration

A Twig filter is available to render AST directly in templates:

{{ content|render_isocontent_ast }}
{{ content|render_isocontent_ast('json') }}

The filter accepts both NodeList objects and raw arrays.

Testing

vendor/bin/phpunit          # Unit & E2E tests
vendor/bin/psalm            # Static analysis
vendor/bin/infection        # Mutation testing
vendor/bin/php-cs-fixer fix # Code style

CI runs on PHP 8.2, 8.3, 8.4, and 8.5 with both lowest and highest dependency versions.

Contributing

Contributions are welcome! Fork the repository, create a feature branch, ensure all checks pass, and open a pull request.

License

Isocontent is released under the MIT License.