feat: lazy-load external images + ability to customize image display (#…

…6990)
facebook · Mar 25, 2022 · dc95cb8 · dc95cb8
1 parent fa50d09
commit dc95cb8
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Showing 4 changed files with 24 additions and 18 deletions.
diff --git a/...ocusaurus-mdx-loader/src/remark/transformImage/__tests__/__snapshots__/index.test.ts.snap b/...ocusaurus-mdx-loader/src/remark/transformImage/__tests__/__snapshots__/index.test.ts.snap
@@ -1,7 +1,7 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
 exports[`transformImage plugin does not choke on invalid image 1`] = `
-"<img loading=\\"lazy\\" alt={\\"invalid image\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/invalid.png\\").default} />
+"<img alt={\\"invalid image\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/invalid.png\\").default} />
 "
 `;
 
@@ -19,29 +19,29 @@ exports[`transformImage plugin pathname protocol 1`] = `
 exports[`transformImage plugin transform md images to <img /> 1`] = `
 "![img](https://example.com/img.png)
 
-<img loading=\\"lazy\\" src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
+<img src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
 
-<img loading=\\"lazy\\" alt={\\"img\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
 
-<img loading=\\"lazy\\" alt={\\"img from second static folder\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static2/img2.png\\").default} width=\\"256\\" height=\\"82\\" />
+<img alt={\\"img from second static folder\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static2/img2.png\\").default} width=\\"256\\" height=\\"82\\" />
 
-<img loading=\\"lazy\\" alt={\\"img from second static folder\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static2/img2.png\\").default} width=\\"256\\" height=\\"82\\" />
+<img alt={\\"img from second static folder\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static2/img2.png\\").default} width=\\"256\\" height=\\"82\\" />
 
-<img loading=\\"lazy\\" alt={\\"img with URL encoded chars\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static2/img2 copy.png\\").default} width=\\"256\\" height=\\"82\\" />
+<img alt={\\"img with URL encoded chars\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static2/img2 copy.png\\").default} width=\\"256\\" height=\\"82\\" />
 
-<img loading=\\"lazy\\" alt={\\"img\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} title=\\"Title\\" width=\\"200\\" height=\\"200\\" /> <img loading=\\"lazy\\" alt={\\"img\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} title=\\"Title\\" width=\\"200\\" height=\\"200\\" /> <img alt={\\"img\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
 
-<img loading=\\"lazy\\" alt={\\"img with &quot;quotes&quot;\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} title=\\"&#39;Quoted&#39; title\\" width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img with &quot;quotes&quot;\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} title=\\"&#39;Quoted&#39; title\\" width=\\"200\\" height=\\"200\\" />
 
-<img loading=\\"lazy\\" alt={\\"site alias\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"site alias\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default} width=\\"200\\" height=\\"200\\" />
 
-<img loading=\\"lazy\\" alt={\\"img with hash\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default + '#light'} width=\\"200\\" height=\\"200\\" />
-<img loading=\\"lazy\\" alt={\\"img with hash\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default + '#dark'} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img with hash\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default + '#light'} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img with hash\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png\\").default + '#dark'} width=\\"200\\" height=\\"200\\" />
 
-<img loading=\\"lazy\\" alt={\\"img with query\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png?w=10\\").default} width=\\"200\\" height=\\"200\\" />
-<img loading=\\"lazy\\" alt={\\"img with query\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png?w=10&h=10\\").default} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img with query\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png?w=10\\").default} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img with query\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png?w=10&h=10\\").default} width=\\"200\\" height=\\"200\\" />
 
-<img loading=\\"lazy\\" alt={\\"img with both\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png?w=10&h=10\\").default + '#light'} width=\\"200\\" height=\\"200\\" />
+<img alt={\\"img with both\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/img.png?w=10&h=10\\").default + '#light'} width=\\"200\\" height=\\"200\\" />
 
 ## Heading
 

diff --git a/packages/docusaurus-mdx-loader/src/remark/transformImage/index.ts b/packages/docusaurus-mdx-loader/src/remark/transformImage/index.ts
@@ -80,7 +80,7 @@ ${(err as Error).message}`;
   );
 
   (jsxNode as Literal).type = 'jsx';
-  jsxNode.value = `<img loading="lazy" ${alt}src={${src}}${title}${width}${height} />`;
+  jsxNode.value = `<img ${alt}src={${src}}${title}${width}${height} />`;
 }
 
 async function ensureImageFileExist(imagePath: string, sourceFilePath: string) {

diff --git a/...ocusaurus-mdx-loader/src/remark/transformLinks/__tests__/__snapshots__/index.test.ts.snap b/...ocusaurus-mdx-loader/src/remark/transformLinks/__tests__/__snapshots__/index.test.ts.snap
@@ -46,7 +46,7 @@ exports[`transformAsset plugin transform md links to <a /> 1`] = `
 
 <a target=\\"_blank\\" href={require('!<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js?name=assets/files/[name]-[contenthash].[ext]!./static/staticAsset.pdf').default}>Just staticAsset.pdf</a>, and <a target=\\"_blank\\" href={require('!<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js?name=assets/files/[name]-[contenthash].[ext]!./static/staticAsset.pdf').default}><strong>awesome</strong> staticAsset 2.pdf &#39;It is really &quot;AWESOME&quot;&#39;</a>, but also <a target=\\"_blank\\" href={require('!<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js?name=assets/files/[name]-[contenthash].[ext]!./static/staticAsset.pdf').default}>coded <code>staticAsset 3.pdf</code></a>
 
-<a target=\\"_blank\\" href={require('!<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js?name=assets/files/[name]-[contenthash].[ext]!./static/staticAssetImage.png').default}><img loading=\\"lazy\\" alt={\\"Clickable Docusaurus logo\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/staticAssetImage.png\\").default} width=\\"200\\" height=\\"200\\" /></a>
+<a target=\\"_blank\\" href={require('!<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js?name=assets/files/[name]-[contenthash].[ext]!./static/staticAssetImage.png').default}><img alt={\\"Clickable Docusaurus logo\\"} src={require(\\"!<PROJECT_ROOT>/node_modules/url-loader/dist/cjs.js?limit=10000&name=assets/images/[name]-[contenthash].[ext]&fallback=<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js!./static/staticAssetImage.png\\").default} width=\\"200\\" height=\\"200\\" /></a>
 
 <a target=\\"_blank\\" href={require('!<PROJECT_ROOT>/node_modules/file-loader/dist/cjs.js?name=assets/files/[name]-[contenthash].[ext]!./asset.pdf').default}><span style={{color: \\"red\\"}}>Stylized link to asset file</span></a>
 

diff --git a/packages/docusaurus-theme-classic/src/theme/MDXComponents/Img.tsx b/packages/docusaurus-theme-classic/src/theme/MDXComponents/Img.tsx
@@ -15,6 +15,12 @@ function transformImgClassName(className?: string): string {
 }
 
 export default function MDXImg(props: Props): JSX.Element {
-  // eslint-disable-next-line jsx-a11y/alt-text
-  return <img {...props} className={transformImgClassName(props.className)} />;
+  return (
+    // eslint-disable-next-line jsx-a11y/alt-text
+    <img
+      loading="lazy"
+      {...props}
+      className={transformImgClassName(props.className)}
+    />
+  );
 }