hast-util-raw

What is hast-util-raw?

The hast-util-raw package is a utility for working with HAST (Hypertext Abstract Syntax Tree) trees. It can parse and transform raw HTML into a HAST tree, allowing for manipulation and analysis of the structure of HTML documents. This package is particularly useful for developers working with virtual DOMs or needing to preprocess or clean HTML content programmatically.

What are hast-util-raw's main functionalities?

Parsing HTML to HAST

This feature allows for the parsing of HTML strings embedded within HAST trees. The `raw` function takes a HAST tree that may contain raw HTML as part of its nodes and returns a new HAST tree with the raw HTML parsed into HAST nodes. This is useful for integrating unescaped HTML strings into a HAST-based workflow.

const raw = require('hast-util-raw');
const h = require('hastscript');
const tree = h('div', [h('span', 'Hello'), '<strong>world!</strong>']);
const result = raw(tree);

Transforming HAST with embedded raw HTML

This demonstrates how `hast-util-raw` can transform a HAST tree that includes a 'raw' node containing HTML into a fully parsed HAST structure. This is particularly useful for scenarios where raw HTML is mixed with HAST content and a uniform HAST structure is needed for further processing.

const raw = require('hast-util-raw');
const u = require('unist-builder');
const tree = u('root', [u('element', {tagName: 'div'}, [u('text', 'Some text'), u('raw', '<span>More text</span>')])]);
const result = raw(tree);

Other packages similar to hast-util-raw

rehype-parse

Similar to hast-util-raw, `rehype-parse` is used for parsing HTML into HAST. However, `rehype-parse` is more focused on being a full HTML parser as part of the rehype ecosystem, offering more comprehensive parsing options and better integration with rehype plugins.

README

hast-util-raw

hast utility to parse the tree again, now supporting embedded raw nodes.

One of the reasons to do this is for “malformed” syntax trees: for example, say there’s an h1 element in a p element, this utility will make them siblings.

Another reason to do this is if raw HTML/XML is embedded in a syntax tree, which can occur when coming from Markdown using mdast-util-to-hast.

If you’re working with remark and/or remark-rehype, use rehype-raw instead.

Install

npm:

npm install hast-util-raw

Use

var h = require('hastscript')
var raw = require('hast-util-raw')

var tree = h('div', [h('h1', ['Foo ', h('h2', 'Bar'), ' Baz'])])

var clean = raw(tree)

console.log(clean)

Yields:

{ type: 'element',
  tagName: 'div',
  properties: {},
  children:
   [ { type: 'element',
       tagName: 'h1',
       properties: {},
       children: [Object] },
     { type: 'element',
       tagName: 'h2',
       properties: {},
       children: [Object] },
     { type: 'text', value: ' Baz' } ] }

API

raw(tree[, file])

Given a hast tree and an optional vfile (for positional info), return a new parsed-again hast tree.

Security

Use of hast-util-raw can open you up to a cross-site scripting (XSS) attack as raw nodes are unsafe. The following example shows how a raw node is used to inject a script that runs when loaded in a browser.

raw(u('root', [u('raw', '<script>alert(1)</script>')]))

Yields:

<script>alert(1)</script>

Do not use this utility in combination with user input or use hast-util-santize.

Related

• mdast-util-to-hast — transform mdast to hast
• rehype-raw — wrapper plugin for rehype

Contribute

See contributing.md in syntax-tree/.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