rehype-external-links

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[rehype][] plugin to add rel (and target) to external links.

* What is this?
* When should I use this?
* Install
* Use
* API
* [unified().use(rehypeExternalLinks[, options])](#unifieduserehypeexternallinks-options)
* CreateContent
* CreateProperties
* CreateRel
* CreateTarget
* Options
* Target
* Types
* Compatibility
* Security
* Contribute
* License

What is this?

This package is a [unified][] ([rehype][]) plugin to add rel (and target)
attributes to external links.
It is particularly useful when displaying user content on your reputable site,
because users could link to disreputable sources (spam, scams, etc), as search
engines and other bots will discredit your site for linking to them (or
legitimize their sites).
In short: linking to something signals trust, but you can’t trust users.
This plugin adds certain rel attributes to prevent that from happening.

unified is a project that transforms content with abstract syntax trees
(ASTs).
rehype adds support for HTML to unified.
hast is the HTML AST that rehype uses.
This is a rehype plugin that adds rel (and target) to s in the AST.

When should I use this?

This project is useful when you want to display user content from authors you
don’t trust (such as comments), as they might include links you don’t endorse,
on your website.

Install

This package is [ESM only][esm].
In Node.js (version 16+), install with [npm][]:

``sh npm install rehype-external-links`

In Deno with [esm.sh][esmsh]:

`js import rehypeExternalLinks from 'https://esm.sh/rehype-external-links@3'`

In browsers with [esm.sh][esmsh]:

`html`

`Use`

Say our module example.js contains:

`js import rehypeExternalLinks from 'rehype-external-links' import remarkParse from 'remark-parse' import remarkRehype from 'remark-rehype' import rehypeStringify from 'rehype-stringify' import {unified} from 'unified'

const file = await unified() .use(remarkParse) .use(remarkRehype) .use(rehypeExternalLinks, {rel: ['nofollow']}) .use(rehypeStringify) .process('rehype')

console.log(String(file))`

…then running node example.js yields:

`html

rehype

API

This package exports no identifiers. The default export is [rehypeExternalLinks][api-rehype-external-links].

`$3`

Automatically add rel (and target?) to external links.

###### Parameters

* options ([Options][api-options], optional) — configuration

###### Returns

Transform ([Transformer][unified-transformer]).

###### Notes

You should [likely not configure target][css-tricks].

You should at least set rel to ['nofollow']. When using atarget, add noopener and noreferrerto avoid exploitation of thewindow.opener API.

When using a target, you should set contentto adhere to accessibility guidelines by [giving users advanced warning when opening a new window][g201].

`$3`

Create a target for the element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

Content to add (Array or Node, optional).

`$3`

Create properties for an element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

Properties to add ([Properties][hast-properties], optional).

`$3`

Create a rel for the element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

rel to use (Array, optional).

`$3`

Create a target for the element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

target to use ([Target][api-target], optional).

`$3`

Configuration (TypeScript type).

###### Fields

* content (Array, [CreateContent][api-create-content], or Node, optional) — content to insert at the end of external links; will be inserted in aelement; useful for improving accessibility by giving users advanced warning when opening a new window *contentProperties ([CreateProperties][api-create-properties] or [Properties][hast-properties], optional) — properties to add to thespan wrapping content*properties ([CreateProperties][api-create-properties] or [Properties][hast-properties], optional) — properties to add to the link itself *protocols (Array, default: ['http', 'https']) — protocols to see as external, such asmailto or tel*rel (Array, [CreateRel][api-create-rel], or string, default:['nofollow']) — [link types][mdn-rel] to hint about the referenced documents; pass an empty array ([]) to not set rels on links; when using a target, add noopenerandnoreferrer to avoid exploitation of the window.openerAPI *target ([CreateTarget][api-create-target] or [Target][api-target], optional) — how to display referenced documents; the default (nothing) is to not settargets on links *test ([Test][is-test], optional) — extra test to define which external link elements are modified; any test that can be given tohast-util-is-element is supported

`$3`

Target (TypeScript type).

###### Type

`ts type Target = '_blank' | '_parent' | '_self' | '_top'`

`Types`

This package is fully typed with [TypeScript][]. It exports the additional types [CreateContent][api-create-content], [CreateProperties][api-create-properties], [CreateRel][api-create-rel], [CreateTarget][api-create-target], [Options][api-options], and [Target][api-target].

`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-external-links@^3, compatible with Node.js 16.

This plugin works with rehype-parse version 3+, rehype-stringifyversion 3+,rehype version 4+, and unified version 6+.

`Security`

Improper use of rehype-external-linkscan open you up to a [cross-site scripting (XSS)][xss] attack.

Either do not combine this plugin with user content or use [rehype-sanitize][rehype-sanitize].

`Contribute`

See [contributing.md][contributing] in [rehypejs/.github][health] for ways to get started. See [support.md`][support] for ways to get help.

This project has a [code of conduct][coc].
By interacting with this repository, organization, or community you agree to
abide by its terms.

License

[MIT][license] © [Titus Wormer][author]

[build-badge]: https://github.com/rehypejs/rehype-external-links/workflows/main/badge.svg

[build]: https://github.com/rehypejs/rehype-external-links/actions

[coverage-badge]: https://img.shields.io/codecov/c/github/rehypejs/rehype-external-links.svg

[coverage]: https://codecov.io/github/rehypejs/rehype-external-links

[downloads-badge]: https://img.shields.io/npm/dm/rehype-external-links.svg

[downloads]: https://www.npmjs.com/package/rehype-external-links

[size-badge]: https://img.shields.io/bundlejs/size/rehype-external-links

[size]: https://bundlejs.com/?q=rehype-external-links

[sponsors-badge]: https://opencollective.com/unified/sponsors/badge.svg

[backers-badge]: https://opencollective.com/unified/backers/badge.svg

[collective]: https://opencollective.com/unified

[chat-badge]: https://img.shields.io/badge/chat-discussions-success.svg

[chat]: https://github.com/rehypejs/rehype/discussions

[npm]: https://docs.npmjs.com/cli/install

[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c

[esmsh]: https://esm.sh

[health]: https://github.com/rehypejs/.github

[contributing]: https://github.com/rehypejs/.github/blob/HEAD/contributing.md

[support]: https://github.com/rehypejs/.github/blob/HEAD/support.md

[coc]: https://github.com/rehypejs/.github/blob/HEAD/code-of-conduct.md

[license]: license

[author]: https://wooorm.com

[hast-properties]: https://github.com/syntax-tree/hast#properties

[is-test]: https://github.com/syntax-tree/hast-util-is-element#test

[mdn-rel]: https://developer.mozilla.org/en-US/docs/Web/HTML/Link_types

[rehype]: https://github.com/rehypejs/rehype

[rehype-sanitize]: https://github.com/rehypejs/rehype-sanitize

[typescript]: https://www.typescriptlang.org

[unified]: https://github.com/unifiedjs/unified

[unified-transformer]: https://github.com/unifiedjs/unified#transformer

[xss]: https://en.wikipedia.org/wiki/Cross-site_scripting

[hast-element]: https://github.com/syntax-tree/hast#element

[g201]: https://www.w3.org/WAI/WCAG21/Techniques/general/G201

[css-tricks]: https://css-tricks.com/use-target_blank/

[api-create-content]: #createcontent

[api-create-properties]: #createproperties

[api-create-rel]: #createrel

[api-create-target]: #createtarget

[api-options]: #options

[api-target]: #target

[api-rehype-external-links]: #unifieduserehypeexternallinks-options

rehype-external-links

[rehype][] plugin to add rel (and target) to external links.

What is this?

When should I use this?

This project is useful when you want to display user content from authors you
don’t trust (such as comments), as they might include links you don’t endorse,
on your website.

Install

This package is [ESM only][esm].
In Node.js (version 16+), install with [npm][]:

``sh npm install rehype-external-links`

In Deno with [esm.sh][esmsh]:

`js import rehypeExternalLinks from 'https://esm.sh/rehype-external-links@3'`

In browsers with [esm.sh][esmsh]:

`html`

`Use`

Say our module example.js contains:

const file = await unified() .use(remarkParse) .use(remarkRehype) .use(rehypeExternalLinks, {rel: ['nofollow']}) .use(rehypeStringify) .process('rehype')

console.log(String(file))`

…then running node example.js yields:

`html

rehype

API

This package exports no identifiers. The default export is [rehypeExternalLinks][api-rehype-external-links].

`$3`

Automatically add rel (and target?) to external links.

###### Parameters

* options ([Options][api-options], optional) — configuration

###### Returns

Transform ([Transformer][unified-transformer]).

###### Notes

You should [likely not configure target][css-tricks].

You should at least set rel to ['nofollow']. When using atarget, add noopener and noreferrerto avoid exploitation of thewindow.opener API.

When using a target, you should set contentto adhere to accessibility guidelines by [giving users advanced warning when opening a new window][g201].

`$3`

Create a target for the element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

Content to add (Array or Node, optional).

`$3`

Create properties for an element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

Properties to add ([Properties][hast-properties], optional).

`$3`

Create a rel for the element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

rel to use (Array, optional).

`$3`

Create a target for the element (TypeScript type).

###### Parameters

* element ([Element][hast-element]) — element to check

###### Returns

target to use ([Target][api-target], optional).

`$3`

Configuration (TypeScript type).

###### Fields

`$3`

Target (TypeScript type).

###### Type

`ts type Target = '_blank' | '_parent' | '_self' | '_top'`

`Types`

`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-external-links@^3, compatible with Node.js 16.

This plugin works with rehype-parse version 3+, rehype-stringifyversion 3+,rehype version 4+, and unified version 6+.

`Security`

Improper use of rehype-external-linkscan open you up to a [cross-site scripting (XSS)][xss] attack.

Either do not combine this plugin with user content or use [rehype-sanitize][rehype-sanitize].

`Contribute`

See [contributing.md][contributing] in [rehypejs/.github][health] for ways to get started. See [support.md`][support] for ways to get help.

This project has a [code of conduct][coc].
By interacting with this repository, organization, or community you agree to
abide by its terms.

License

[build-badge]: https://github.com/rehypejs/rehype-external-links/workflows/main/badge.svg

[build]: https://github.com/rehypejs/rehype-external-links/actions

[coverage-badge]: https://img.shields.io/codecov/c/github/rehypejs/rehype-external-links.svg

[coverage]: https://codecov.io/github/rehypejs/rehype-external-links

[downloads-badge]: https://img.shields.io/npm/dm/rehype-external-links.svg

[downloads]: https://www.npmjs.com/package/rehype-external-links

[size-badge]: https://img.shields.io/bundlejs/size/rehype-external-links

[size]: https://bundlejs.com/?q=rehype-external-links

[sponsors-badge]: https://opencollective.com/unified/sponsors/badge.svg

[backers-badge]: https://opencollective.com/unified/backers/badge.svg

[collective]: https://opencollective.com/unified

[chat-badge]: https://img.shields.io/badge/chat-discussions-success.svg

[chat]: https://github.com/rehypejs/rehype/discussions

[npm]: https://docs.npmjs.com/cli/install

[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c

[esmsh]: https://esm.sh

[health]: https://github.com/rehypejs/.github

[contributing]: https://github.com/rehypejs/.github/blob/HEAD/contributing.md

[support]: https://github.com/rehypejs/.github/blob/HEAD/support.md

[coc]: https://github.com/rehypejs/.github/blob/HEAD/code-of-conduct.md

[license]: license

[author]: https://wooorm.com

[hast-properties]: https://github.com/syntax-tree/hast#properties

[is-test]: https://github.com/syntax-tree/hast-util-is-element#test

[mdn-rel]: https://developer.mozilla.org/en-US/docs/Web/HTML/Link_types

[rehype]: https://github.com/rehypejs/rehype

[rehype-sanitize]: https://github.com/rehypejs/rehype-sanitize

[typescript]: https://www.typescriptlang.org

[unified]: https://github.com/unifiedjs/unified

[unified-transformer]: https://github.com/unifiedjs/unified#transformer

[xss]: https://en.wikipedia.org/wiki/Cross-site_scripting

[hast-element]: https://github.com/syntax-tree/hast#element

[g201]: https://www.w3.org/WAI/WCAG21/Techniques/general/G201

[css-tricks]: https://css-tricks.com/use-target_blank/

[api-create-content]: #createcontent

[api-create-properties]: #createproperties

[api-create-rel]: #createrel

[api-create-target]: #createtarget

[api-options]: #options

[api-target]: #target

[api-rehype-external-links]: #unifieduserehypeexternallinks-options

rehype-external-links

rehype-external-links

Contents

What is this?

When should I use this?

Install

`Use`

API

`$3`

`$3`

`$3`

`$3`

`$3`

`$3`

`$3`

`Types`

`Compatibility`

`Security`

`Contribute`

License

rehype-external-links

rehype-external-links

Contents

What is this?

When should I use this?

Install

`Use`

API

`$3`

`$3`

`$3`

`$3`

`$3`

`$3`

`$3`

`Types`

`Compatibility`

`Security`

`Contribute`

License