recma-mdx-import-media

This package is a unified (recma) plugin that turns media relative paths into import declarations for both markdown and html syntax in MDX

unified is a project that transforms content with abstract syntax trees (ASTs) using the new parser micromark. recma adds support for producing a javascript code by transforming esast which stands for Ecma Script Abstract Syntax Tree (AST) that is used in production of compiled source for the MDX.

When should I use this?

recma-mdx-import-media is working for only images for now, other assets will be added in next versions !

If you're working with MDX and want to include media/asset with relative path using markdown syntax, without providing an import statement, such as:

![alt](./image.png)

![alt](../blog-assets/image.png)

If you're working with MDX and want to include media/asset with relative path using html syntax, without providing an import statement, such as:

<img src="./image.png" alt="alt" />

<img src="../blog-assets/image.png" alt="alt" />

Because, recma-mdx-import-media creates import statements and assign the identifier into proper element in the compiled source.

recma-mdx-import-media only processes relative paths (starts with ./ or ../); leaving protocol-like patterns (like http://), root-relative URLs (like /pathname), and absolute paths (file:///) unchanged.

You might run into issues because bundlers like Webpack and Vite don't natively recognize these references (.png, .jpeg etc.)—they only handle imports. recma-mdx-import-media bridges that gap by converting media relative references into import declarations in compiled MDX source, ensuring bundlers can process them correctly, for both markdown and HTML syntax.

Installation

This package is suitable for ESM only. In Node.js (version 18+), install with npm:

npm install recma-mdx-import-media

yarn add recma-mdx-import-media

Usage

Say we have the following file, example.mdx,

![alt](./image.png)

<img src="../../image.png" alt="alt" />

And our module, example.js, looks as follows:

import { read } from "to-vfile";
import { compile } from "@mdx-js/mdx";
import recmaMdxImportMedia from "recma-mdx-import-media";

main();

async function main() {
  const source = await read("example.mdx");

  const compiledSource = await compile(source, {
    recmaPlugins: [recmaMdxImportMedia],
  });

  return String(compiledSource);
}

Now, running node example.js produces the compiled source like below:

// ...
+ import imagepng$recmamdximport from "./image.png";
+ import imagepng_1$recmamdximport from "../../image.png";
function _createMdxContent(props) {
  const _components = {
    img: "img",
    p: "p",
    ...props.components
  };
  return _jsxs(_Fragment, {
    children: [_jsx(_components.p, {
      children: _jsx(_components.img, {
-        src: "./image.png",
+        src: imagepng$recmamdximport,
        alt: "alt"
      })
    }), "\\n", _jsx("img", {
-      src: "../../image.png",
+      src: imagepng_1$recmamdximport,
      alt: "alt"
    })]
  });
}
// ...

Options

All options are optional.

export type ImportMediaOptions = {
  excludeSyntax?: Array<"markdown" | "html">; // default is empty array []
};

excludeSyntax

It is an array option to exlude markdown or html syntax or both. The option are self-explainotary.

use(recmaMdxImportMedia, { excludeSyntax: ["html"] } as ImportMediaOptions);

Now, <img /> like html syntax will be excluded.

use(recmaMdxImportMedia, { excludeSyntax: ["markdown"] } as ImportMediaOptions);

Now, ![]()) like markdown syntax will be excluded.

use(recmaMdxImportMedia, { excludeSyntax: ["html", "markdown"] } as ImportMediaOptions);

Now, both html and markdown syntax will be excluded. The plugin becomes effectless.

Syntax tree

This plugin only modifies the ESAST (Ecma Script Abstract Syntax Tree) as explained.

Types

This package is fully typed with TypeScript. The plugin options is exported as ImportMediaOptions.

Compatibility

This plugin works with unified version 6+. It is compatible with mdx version 3+.

Security

Use of recma-mdx-import-media does not involve user content so there are no openings for cross-site scripting (XSS) attacks.

My Plugins

I like to contribute the Unified / Remark / MDX ecosystem, so I recommend you to have a look my plugins.

My Remark Plugins

remark-flexible-code-titles – Remark plugin to add titles or/and containers for the code blocks with customizable properties
remark-flexible-containers – Remark plugin to add custom containers with customizable properties in markdown
remark-ins – Remark plugin to add ins element in markdown
remark-flexible-paragraphs – Remark plugin to add custom paragraphs with customizable properties in markdown
remark-flexible-markers – Remark plugin to add custom mark element with customizable properties in markdown
remark-flexible-toc – Remark plugin to expose the table of contents via vfile.data or via an option reference
remark-mdx-remove-esm – Remark plugin to remove import and/or export statements (mdxjsEsm)

My Rehype Plugins

rehype-pre-language – Rehype plugin to add language information as a property to pre element
rehype-highlight-code-lines – Rehype plugin to add line numbers to code blocks and allow highlighting of desired code lines

My Recma Plugins

recma-mdx-escape-missing-components – Recma plugin to set the default value () => null for the Components in MDX in case of missing or not provided so as not to throw an error
recma-mdx-change-props – Recma plugin to change the props parameter into the _props in the function _createMdxContent(props) {/* */} in the compiled source in order to be able to use {props.foo} like expressions. It is useful for the next-mdx-remote or next-mdx-remote-client users in nextjs applications.
recma-mdx-change-imports – Recma plugin to convert import declarations for assets and media with relative links into variable declarations with string URLs, enabling direct asset URL resolution in compiled MDX.
recma-mdx-import-media – Recma plugin to turn media relative paths into import declarations for both markdown and html syntax in MDX.