src/pages/post/[...slug].astro

@@ -33,7 +33,7 @@ let matchedImage_src;
 if (matchedImage && !customFeaturedImage) {
     matchedImage_src = await getImage({src: featuredImages[matchedImage], format: 'webp'}) || null;
 }
-const firstImageURL = await ExtractFirstImage(Content)
+const firstImageURL = await ExtractFirstImage(Content,Astro.url.origin)
 
 const cover = customFeaturedImage || matchedImage_src?.src || firstImageURL || `/post/${slug}/featured.png` || '';
 ---

src/pages/post/[slug]/featured.png.js

@@ -20,22 +20,14 @@ async function getExternalImage(post) {
   return matchedImage_?.src;
 }
 
-// Function to check for images in markdown without rendering
-function checkForImages(markdownContent) {
-  // Match markdown image syntax ![alt](url) or HTML <img> tags
-  const imageRegex = /!\[.*?]\(.*?\)|<img.*?src=["'].*?["'].*?>/g;
-  return imageRegex.test(markdownContent);
-}
-
 // This function dynamically generates og:images for posts that don't have a featured image
 export async function GET({ props }) {
   const {post} = props;
   const ExternalImageURL = await getExternalImage(post);
-  const hasImage = checkForImages(post.body);
   try {
     // Check if a custom cover image already exists
-    if (post.data.cover || ExternalImageURL || hasImage) {
-      // set it to empty to prevent the image generation
+    if (post.data.cover || ExternalImageURL) {
+      // Redirect to the existing image
       return new Response(null);
     }
 

src/plugins/extract-images.js

@@ -3,7 +3,7 @@ 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) {
+export async function ExtractFirstImage(Content, baseUrl = '') {
     // 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()]);
 
@@ -22,7 +22,15 @@ export async function ExtractFirstImage(Content) {
             await walk(node, (node) => {
                 if (node.name === "img" && node.attributes.src) {
                     // Store the first image URL we find
-                    firstImageUrl = node.attributes.src;
+                    if (!firstImageUrl) {
+                        firstImageUrl = node.attributes.src.startsWith("/")
+                            ? baseUrl + node.attributes.src
+                            : node.attributes.src;
+                    }
+                    // Still update the src attribute if needed
+                    if (node.attributes.src.startsWith("/")) {
+                        node.attributes.src = baseUrl + node.attributes.src;
+                    }
                 }
             });
             return node;