Server-side GitHub Flavored Markdown rendering for Deno, including GitHub style CSS, syntax highlighting, and HTML sanitization.
First install the package with the command:
deno add @deno/gfm
import { CSS, render } from "@deno/gfm";
const markdown = `
# Hello, world!
| Type | Value |
| ---- | ----- |
| x | 42 |
\`\`\`js
console.log("Hello, world!");
\`\`\`
`;
const body = render(markdown, {
baseUrl: "https://example.com",
});
const html = `
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<style>
main {
max-width: 800px;
margin: 0 auto;
}
${CSS}
</style>
</head>
<body>
<main data-color-mode="light" data-light-theme="light" data-dark-theme="dark" class="markdown-body">
${body}
</main>
</body>
</html>
`;
The GitHub CSS styles (https://primer.style) are used. There are two themes available: light and dark.
There are three data attributes that can be used to control the theme:
data-color-mode: light or dark or auto.data-light-theme: the name of the light theme (light or dark).data-dark-theme: the name of the dark theme (light or dark).For example, if you want to use the dark theme only, set the following:
... markdown body here ...
If you want to use the light or dark theme depending on the user's browser preference, set the following:
... markdown body here ...
Also see the example application in the example/ directory.
By default syntax highlighting for JavaScript, Markdown, and HTML is included. You can include more languages importing them:
import { CSS, render } from "@deno/gfm";
// Add support for TypeScript, Bash, and Rust.
import "npm:prismjs@1.29.0/components/prism-typescript.js";
import "npm:prismjs@1.29.0/components/prism-bash.js";
import "npm:prismjs@1.29.0/components/prism-rust.js";
A full list of supported languages is available here: https://unpkg.com/browse/prismjs@1.29.0/components/
By default, all rendering is in blocks. There are cases where one would like to
render some inline markdown, and this is achievable using the inline setting:
import { render } from "@deno/gfm";
const markdown = "My [Deno](https://deno.land) Blog";
const header = render(markdown, { inline: true });
console.log(header);
By default math rendering is disabled. To enable it, you must include the
additional CSS and enable the allowMath setting:
import { CSS, KATEX_CSS, render } from "jsr:@deno/gfm";
const markdown = `
Block math:
$$ y = x^2 $$
Inline math: $y = x^2$
`;
const body = render(markdown, {
allowMath: true,
});
const html = `
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<style>
main {
max-width: 800px;
margin: 0 auto;
}
${CSS}
${KATEX_CSS}
</style>
</head>
<body>
<main data-color-mode="light" data-light-theme="light" data-dark-theme="dark" class="markdown-body">
${body}
</main>
</body>
</html>
`;
$ claude mcp add deno-gfm \
-- python -m otcore.mcp_server <graph>