rehype VS hast

Add Remark and Rehype plugins

Astro content collection are as simple as a folder containing a bunch of Markdown (or Markdoc or MDX) files if that's the only thing you need, but they can also do relationship matching between different collections, frontmatter validation using zod and you can also customize how the markdown is parsed and translated to html using rehype and remark and their plugin ecosystem.

That's all to render the post as HTML, there are lots of things you can do to customize the results, you can check the remark plugins and rehype plugins to pass as props to and you can also take a look at some other bloggers if you're looking for different styles for example Lee Robinson's or if you liked mine.

Now we have our Cloudinary account set up, we can use it with Docusaurus. To do so, we need to create a rehype plugin. This is a plugin for the rehype HTML processor. It's a plugin that will transform the HTML image syntax into a Cloudinary URL.

The next idea was to use normal markdown images and to place the images in the public folder. This eliminates the need for static import and treats our image like a remote image. But in order to make this work, we have to tell next/image the dimensions of the image. If we would use a static import for the image, the import magic would provide the dimensions for us. To pass the width and height to the image component we use a rehype plugin called rehype-img-size.

Astro makes it easy to add Remark or Rehype plugins to your markdown. You can extend add a markdown property to the Astro config file, an add a function/plugin to the remarkPlugins property (the extendDefaultPlugins property is added to make sure the default plugins aren't overwritten by this config change):

rehype: "rehype is a tool that transforms HTML with plugins. These plugins can inspect and change the HTML. You can use rehype on the server, the client, CLIs, deno, etc."

This means that you can transform your HTML with tools like rehype or remark. You can find out more about the available options here.

The HTML syntax tree is transformed through rehype, and rendered to React components.

contentlayer uses remark to parse the markdown in an mdast. We can now use remark plugins to modify the mdast. Then rehype comes into play and converts the mdast into a hast. rehype plugins can now modify the hast. Finally the hast is converted into react components.

remark-rehype translates the mdast structure into a Hypertext Abstract Syntax Tree (hast) structure, also composed of unist nodes.

We have to pass hast elements thought. If you want to read more about hast elements, check out this documentation link.

Is it so hard to accept that a tool or app could compile a html document into some intermediate form and then use that to internally construct a DOM representation, maybe out of a cache?