mercury/src/plugins/extract-images.js

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1.4 KiB
JavaScript

import {loadRenderers} from "astro:container";
import {getContainerRenderer as getMDXRenderer} from "@astrojs/mdx";
import {experimental_AstroContainer as AstroContainer} from "astro/container";
import {transform, walk} from "ultrahtml";
export async function ExtractFirstImage(Content) {
// Load MDX renderer. Other renderers for UI frameworks (e.g. React, Vue, etc.) would need adding here if you were using those.
const renderers = await loadRenderers([getMDXRenderer()]);
// Create a new Astro container that we can render components with.
// See https://docs.astro.build/en/reference/container-reference/
const container = await AstroContainer.create({renderers});
// Use the Astro container to render the content to a string.
const rawContent = await container.renderToString(Content);
let firstImageUrl = null;
// The transform function returns a promise, so we need to await it
await transform(rawContent.replace(/^<!DOCTYPE html>/, ''), [
async (node) => {
await walk(node, (node) => {
if (node.name === "img" && node.attributes.src) {
// Store the first image URL we find
firstImageUrl = node.attributes.src;
}
});
return node;
}
]);
// Return the URL value, not a Promise
return firstImageUrl;
}