README

One model of a manual, whatever wrote it. A manual has versions; a version has a home, its contents (pages, and sections holding pages), its pages - a title, an HTML body, the headings with their anchors, the file to edit - and its API entries (Symbol: a class, a function, an option... on a page, at an anchor). Each format is a provider that implements one SourceInterface:

What the core adds over the sources:

• OnePage: a version read as one page - the home, then every page as a part, its headings one level down and its ids prefixed so that none meet, links between pages turned into anchors of the page, the table of contents (h2/h3, or the top-level sections as groups with groups: true) for a sidebar, its entries disclosures (the one read open, the reader's choices kept), and the former address of each page with the part it became, for a static redirection that carries the visitor's #fragment over (omnibridge/static);
• Search\SearchIndex: the JSON a static page searches - a record per page (or part), per heading, per API entry, plus the site's own;
• Html\Conventions: the HTML every source writes - callouts (note, tip, warning, seealso, versionadded, deprecated), version badges, code frames with captions, code tabs;
• assets/omnidocs.js and assets/omnidocs.css: the reader's side - the search palette (⌘ K, Ctrl K or /; the browser's ⌘ F is left alone), the sticky table of contents that follows the reading and keeps the address on the section read (history.replaceState: nothing added to the history), its drawer on a phone, code tabs, copy buttons; Bridge/Twig/templates the table of contents and the search button as Twig partials;
• Testing\SourceContractTests: the conformance suite every source passes.

It requires PHP 8.2 alone: no framework, no template engine.

use Omnidocs\Linking\RepositoryLinker;
use Omnidocs\Markdown\MarkdownSourceFactory;
use Omnidocs\Model\Manual;
use Omnidocs\Model\Version;
use Omnidocs\OnePage;
use Omnidocs\Registry;
use Omnidocs\Search\SearchIndex;

$docs = new Registry([new MarkdownSourceFactory()], [
    'manual' => ['factory' => 'markdown', 'options' => ['root' => '/path/to/flowjs', 'home' => 'README.md']],
]);
$manual = new Manual('flowjs', 'Flow', [new Version('1.x', $docs->get('manual'), 'master', 'c417356')]);
$links = new RepositoryLinker(fn (string $path, ?string $anchor) => '/docs/'.$path.($anchor ? '#'.$anchor : ''), 'glitchr-studio/flowjs', 'c417356');

$one = new OnePage($manual->version(), $links, '/docs');
$one->parts();   // the home, then each page: title, anchor, HTML, the file to edit
$one->toc();     // the sidebar
file_put_contents('search.json', (new SearchIndex())->onePage($one, 'Flow')->toJson('en'));

Documentation

• Installation and a manual in plain PHP
• The model and the sources
• One page per manual, the sidebar, the search
• The HTML conventions
• The Docker harness

Verified, and not

• Verified (docker compose run --rm omnidocs test in docker/, PHP 8.4): every package's suite - the conformance suite on each provider's real fixture, the core's own model, one page, search index, conventions, registry; BareTest in each package (every class loaded with Composer's autoloader alone, no framework class); docker/harness/bin/bare (a manual built by hand, its pages, its search index, nothing loaded but omnidocs); node --test Tests/js/omnidocs.test.cjs (the palette's ranking, marks, and ⌘ F left to the browser).
• Verified on the tools' whole output (docker compose run --rm sphinx, doxygen, jsdoc, then omnidocs real): Requests' 15 documents and the 167 API entries of its 223-line inventory (its std: labels left out), TinyXML-2's main page and 24 compounds with 407 entries, flowjs' 3 988 doclets read as 7 globals and 299 public entries.
• Verified in use: the Omnisense site (153 manuals, one page each, 150 PHP API references) and the flowjs site, built statically and read in headless Chrome.
• Not verified: Sphinx themes' own JSON additions beyond the standard builder; Sphinx projects written with MyST (Markdown) - the JSON builder writes the same HTML, not tried; Doxygen's C#, Java and Python output; TypeDoc (see omnidocs/jsdoc's README: why JSDoc).

Licence: MIT.