sanitize()

Create a sanitization plugin that strips dangerous HTML tags, attributes, and URL protocols from compiled output.

import { sanitize } from "@unifast/node";

Signature

function sanitize(options?: SanitizePluginOptions): UnifastPlugin

Parameters

options?

Sanitization configuration

Property	Type	Default	Description
`enabled`	`boolean`	`true`	Enable or disable sanitization
`schema`	`SanitizeSchema`	—	Custom sanitization schema

SanitizeSchema

Property	Type	Description
`allowedTags`	`string[]`	HTML tag names to allow (all others are stripped)
`allowedAttributes`	`Record<string, string[]>`	Map of tag name to allowed attribute names
`allowedProtocols`	`Record<string, string[]>`	Map of attribute name to allowed URL protocols

Usage

import { compile, sanitize } from "@unifast/node";

const result = compile(md, {
  plugins: [
    sanitize({
      enabled: true,
      schema: {
        allowedTags: ["h1", "h2", "h3", "p", "a", "strong", "em", "code", "pre", "img", "ul", "ol", "li", "blockquote", "table", "thead", "tbody", "tr", "th", "td"],
        allowedAttributes: {
          a: ["href", "title", "target"],
          img: ["src", "alt", "width", "height"],
          code: ["class"],
          pre: ["class"],
        },
        allowedProtocols: {
          href: ["https", "http", "mailto"],
          src: ["https", "http"],
        },
      },
    }),
  ],
});

Examples

Strip dangerous HTML

import { compile, sanitize } from "@unifast/node";

const untrustedMd = `
# Hello

<script>alert("xss")</script>

<img src="x" onerror="alert('xss')">

[Click me](javascript:alert('xss'))
`;

const result = compile(untrustedMd, {
  plugins: [sanitize()],
});

console.log(result.output);
// <script> tags, onerror attributes, and javascript: URLs are removed

Custom allowed tags

import { compile, sanitize } from "@unifast/node";

const result = compile(md, {
  plugins: [
    sanitize({
      schema: {
        allowedTags: ["p", "a", "strong", "em", "code", "pre"],
      },
    }),
  ],
});

console.log(result.output);
// Only the specified tags are kept; all others are stripped

Restrict URL protocols

import { compile, sanitize } from "@unifast/node";

const result = compile(md, {
  plugins: [
    sanitize({
      schema: {
        allowedProtocols: {
          href: ["https", "mailto"],
          src: ["https"],
        },
      },
    }),
  ],
});

console.log(result.output);
// Only https: and mailto: links are allowed

Disable sanitization

import { compile, sanitize } from "@unifast/node";

const result = compile(md, {
  plugins: [sanitize({ enabled: false })],
});

console.log(result.output);
// No sanitization applied — use only with trusted input