rehype plugin to infer the title of a document.
Contents
What is this?
This package is a unified (rehype) plugin to infer the title of a document.
unified is a project that transforms content with abstract syntax trees (ASTs). rehype adds support for HTML to unified. vfile is the virtual file interface used in unified. hast is the HTML AST that rehype uses. This is a rehype plugin that inspects hast and adds metadata to vfiles.
When should I use this?
This plugin is particularly useful in combination with rehype-document or rehype-meta. When both are used together, the <title> is populated with the document’s title.
Install
This package is ESM only. In Node.js (version 16+), install with npm:
npm install rehype-infer-title-meta
In Deno with esm.sh:
import rehypeInferTitleMeta from 'https://esm.sh/rehype-infer-title-meta@2'
In browsers with esm.sh:
<script type="module">
import rehypeInferTitleMeta from 'https://esm.sh/rehype-infer-title-meta@2?bundle'
</script>
Use
Say our module example.js looks as follows:
import rehypeDocument from 'rehype-document'
import rehypeFormat from 'rehype-format'
import rehypeInferTitleMeta from 'rehype-infer-title-meta'
import rehypeStringify from 'rehype-stringify'
import remarkParse from 'remark-parse'
import remarkRehype from 'remark-rehype'
import {unified} from 'unified'
const file = await unified()
.use(remarkParse)
.use(remarkRehype)
.use(rehypeInferTitleMeta)
.use(rehypeDocument)
.use(rehypeFormat)
.use(rehypeStringify)
.process('# Hello, world!')
console.log(file.data)
console.log(String(file))
…now running node example.js yields:
{meta: {title: 'Hello, world!'}}
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Hello, world!</title>
<meta content="width=device-width, initial-scale=1" name="viewport">
</head>
<body>
<h1>Hello, world!</h1>
</body>
</html>
API
This package exports no identifiers. The default export is rehypeInferTitleMeta.
Infer file metadata from the main title of a document.
The result is stored on file.data.meta.title.
Parameters
options (Options, optional) — configuration
Returns
Transform (Transformer).
Options
Configuration (TypeScript type).
Fields
selector (string, default: 'h1') — CSS selector to the title; can be a selector list (such as 'title, h1, .main-heading'), in which case the first element in the tree that matches is used
Types
This package is fully typed with TypeScript. It exports the additional type Options.
It also registers file.data.meta with vfile. If you’re working with the file, make sure to import this plugin somewhere in your types, as that registers the new fields on the file.
/**
* @typedef {import('rehype-infer-title-meta')}
*/
import {VFile} from 'vfile'
const file = new VFile()
console.log(file.data.meta.title) //=> TS now knows that this is a `string?`.
Compatibility
Projects maintained by the unified collective are compatible with maintained versions of Node.js.
When we cut a new major release, we drop support for unmaintained versions of Node. This means we try to keep the current release line, rehype-infer-title-meta@^2, compatible with Node.js 16.
This plugin works with rehype-parse version 3+, rehype-stringify version 3+, rehype version 4+, and unified version 6+.
Security
Use of rehype-infer-title-meta is safe.
Contribute
See contributing.md in rehypejs/.github for ways to get started. See support.md for ways to get help.
This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.
License
MIT © Titus Wormer