remark-card

A remark plugin to parse card layout component(s). It consists of these two elements:

• card-grid
  • A container for cards that helps users work on the CSS grid layout or the likes
• card
  • Self-explanatory

Features

• Compatible with the proposed generic syntax for custom directives/plugins in Markdown
• Fully customizable styles
• Written in TypeScript
• ESM only

How to Use

Installation

To install the plugin:

With npm:

npm install remark-card

With yarn:

yarn add remark-card

With pnpm:

pnpm add remark-card

With bun:

bun install remark-card

Usage

General usage:

import rehypeStringify from "rehype-stringify";
import remarkCard from "remark-card";
import remarkDirective from "remark-directive";
import remarkParse from "remark-parse";
import remarkRehype from "remark-rehype";
import { unified } from "unified";

const normalizeHtml = (html: string) => {
  return html.replace(/[\n\s]*(<)|>([\n\s]*)/g, (_match, p1, _p2) =>
    p1 ? "<" : ">"
  );
};

const parseMarkdown = async (markdown: string) => {
  const remarkProcessor = unified()
    .use(remarkParse)
    .use(remarkDirective)
    .use(remarkCard)
    .use(remarkRehype)
    .use(rehypeStringify);

  const output = String(await remarkProcessor.process(markdown));

  return output;
}

const input = `
:::card
![image alt](https://xxxxx.xxx/yyy.jpg)
Card content
`

const html = await parseMarkdown(input);

console.log(normalizeHtml(html));

Yields:

<div>
  <div class="image-container">
    <img src="https://xxxxx.xxx/yyy.jpg" alt="image alt" />
  </div>
  <div class="content-container">Card content</div>
</div>

At the moment, it takes the following option(s):

export type Config = {
  // Whether or not to use custom HTML tags for both `card` and `card-grid`. By default, it's set to `false`.
  customHTMLTags?: {
    enabled: boolean;
  };
  cardGridClass?: string;
  cardClass?: string;
  imageContainerClass?: string;
  contentContainerClass?: string;
}

[!NOTE] Why do we need those card & card grid class options? - Since MDX 2, the compiler has come to throw an error "Could not parse expression with acorn: $error" whenever there are unescaped curly braces and the expression inside them is invalid. This breaking change leads the directive syntax (:::xxx{a=b}) to cause the error, so the options are like an escape hatch for that situation.

For more possible patterns and in-depths explanations on the generic syntax(e.g., :::something[...]{...}), see ./test/index.test.ts and this page, respectively.

Syntax

card

For example, the following Markdown content:

:::card{.card#card-id}
![image alt](https://xxxxx.xxx/yyy.jpg)
Card content
:::

Yields:

<div id="card-id" class="card">
  <div class="image-container">
    <img src="https://xxxxx.xxx/yyy.jpg" alt="image alt" />
  </div>
  <div class="content-container">Card content</div>
</div>

card-grid

The card-grid element can be used in combination with the card element.

For example, the following Markdown content:

::::card-grid{.card-grid}
:::card{.card-1}
![card 1](https://xxxxx.xxx/yyy.jpg)
Card 1
:::
:::card{.card-2}
![card 2](https://xxxxx.xxx/yyy.jpg)
Card 2
:::
:::card{.card-3}
![card 3](https://xxxxx.xxx/yyy.jpg)
Card 3
:::
::::

Yields:

<div class="card-grid">
  <div class="card-1">
    <div class="image-container">
      <img src="https://xxxxx.xxx/yyy.jpg" alt="card 1">
    </div>
    <div class="content-container">Card 1</div>
  </div>
  <div class="card-2">
    <div class="image-container">
      <img src="https://xxxxx.xxx/yyy.jpg" alt="card 2">
    </div>
    <div class="content-container">Card 2</div>
  </div>
  <div class="card-3">
    <div class="image-container">
      <img src="https://xxxxx.xxx/yyy.jpg" alt="card 3">
    </div>
    <div class="content-container">Card 3</div>
  </div>
</div>

Astro

If you want to use this in your Astro project, note that you need to install remark-directive and add it to the astro.config.{js,mjs,ts} file simultaneously.

import { defineConfig } from 'astro/config';
import remarkCard from "remark-card";
import remarkDirective from "remark-directive";
// ...

export default defineConfig({
  // ...
  markdown: {
    // ...
    remarkPlugins: [
      // ...
      remarkDirective,
      remarkCard,
      // ...
    ]
    // ...
  }
  // ...
})

Also, if you want to use your Astro component(s) for customization purposes, make sure to set the customHTMLTags.enabled to true and assign your custom components like this:

~/lib/mdx-components.ts

import { Card, CardGrid } from '~/components/elements/Card';
// ...

export const mdxComponents = {
  // ...
  card: Card,
  'card-grid': CardGrid,
  // ...
};

~/pages/page.astro

---
import { mdxComponents } from '~/lib/mdx-components';

// ...

const { page } = Astro.props;
const { Content } = await page.render();
---

<Layout>
  <Content components={mdxComponents}>
</Layout>

How it works

Some key takeaways are:

• The former will be prioritized and used as the alt value of img if both the image alt and the card alt are provided
• Both card and card-grid take common & custom HTML attributes
  • their styles are customizable by providing user-defined CSS class(es)
    • e.g., border, background-color, etc.
• The default values of this plugin's options:
  • customHTMLTags.enabled: false
  • imageContainerClass: "image-container"
  • contentContainerClass: "content-container"
  • cardGridClass: undefined
  • cardClass: undefined

Feature(s) pending to be added

• Nested cards
  • It seems technically feasible but the use case of this might be rare ~~- Customizable class names for image & content containers~~

TODO(s)

• [ ] add a demo screenshot of the actual card-grid & card combination to this page
• [x] add customizable class name options for image & content containers

License

This project is licensed under the MIT License, see the LICENSE file for more details.