rehype-infer-title-meta
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-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 12.20+, 14.14+, 16.0+, or 18.0+), install with npm:
npm install rehype-infer-title-meta
In Deno with esm.sh:
import rehypeInferTitleMeta from 'https://esm.sh/rehype-infer-title-meta@1'
In browsers with esm.sh:
<script type="module">
import rehypeInferTitleMeta from 'https://esm.sh/rehype-infer-title-meta@1?bundle'
</script>
Use
Say our module example.js looks as follows:
import {unified} from 'unified'
import remarkParse from 'remark-parse'
import remarkRehype from 'remark-rehype'
import rehypeInferTitleMeta from 'rehype-infer-title-meta'
import rehypeDocument from 'rehype-document'
import rehypeMeta from 'rehype-meta'
import rehypeFormat from 'rehype-format'
import rehypeStringify from 'rehype-stringify'
const file = await unified()
.use(remarkParse)
.use(remarkRehype)
.use(rehypeDocument)
.use(rehypeInferTitleMeta)
.use(rehypeMeta)
.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">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Hello, world!</title>
</head>
<body>
<h1>Hello, world!</h1>
</body>
</html>
API
This package exports no identifiers. The default export is rehypeInferTitleMeta.
unified().use(rehypeInferTitleMeta, options?)
Infer the title from a document as file metadata. The result is stored on file.data.meta.title.
options
Configuration (optional).
options.selector
CSS selector to the title (string, default: 'h1'). Can be a selector list ('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. The additional type Options is exported.
It also registers the file.data.meta field with vfile. If you’re working with the file, make sure to import this plugin somewhere in your types, as that registers the new field 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 all maintained versions of Node.js. As of now, that is Node.js 12.20+, 14.14+, 16.0+, and 18.0+. Our projects sometimes work with older versions, but this is not guaranteed.
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.
Related
rehype-document— wrap a fragment in a documentrehype-meta— add metadata to the head of a documentunified-infer-git-meta— infer file metadata from Gitrehype-infer-description-meta— infer file metadata from the description of a documentrehype-infer-reading-time-meta— infer file metadata from the reading time of a document
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.