Astro Feature Test: MDX from CMS

Astro Component

import Highlight from '@components/Highlight.astro';

<Highlight>
	Test: Plain Astro Component with `click` event listener
	<button onclick="alert('button clicked')">Test</button>
</Highlight>

Svelte Component

Caution: the empty line between the import statement and the <Component /> is mandatory.

import Counter from '@components/Counter.svelte';

<Counter client:visible="svelte" value="5" />

Caution: Currently, there’s a known bug in Astro and component styles aren’t imported properly at build time

Update: using Notion code blocks

Using a custom transformer for notion-to-md:

n2m.setCustomTransformer('code', async (block) => {
	/**
	 *   type: 'code',
	 *   code: { caption: [], rich_text: [ [Object] ], language: 'markdown' }
	 */
	const { code } = block

	if (code?.language === 'markdown') {
		return code?.rich_text?.map((chunk) => chunk?.plain_text)?.join('')
	}

	return block
})

the input with language === markdown:

<Counter client:visible="svelte" value="10" />

will be treated as a mdx component reference:

Bonus - lazyload Svelte component (hydrate on demand)

The trick is to

• wrap the component in an Astro HTML wrapper with display: none
• use the client:visible directive
• programatically change the visibility of the wrapper which will trigger the component import and the hydration

Sources

• MDX documentation
• Astro + MDX documentation
• notion-to-md: custom transformers