Image Adaptive WebP
This example determines whether the request header
Accept
contains image/webp
. If so, the Edge function will automatically convert the image format to WebP
and cache it on the EdgeOne edge node. If your Web application displays a large amount of PNG
and JPEG
format images and you want to automatically optimize the images at the edge to reduce traffic bandwidth costs, you can use Edge functions to implement a smooth upgrade, automatically converting PNG
and JPEG
format images to WebP
format with 0 changes to the business code. For more image conversion formats, please refer to ImageProperties.Note:
This example can execute the conversion feature normally only when the MIME type specified in the response header
Content-Type
of the source file is an image (image/*
).This example does not currently support converting
SVG
format images.It is recommended to add image file extensions such as
.png
, .jpeg
, and .jpg
to the edge function triggering rules.async function handleEvent(event) {const { request } = event;// Get the image type supported by the clientconst accept = request.headers.get('Accept');const option = { eo: { image: {} } };// Check whether the client supports WebP format images, if not, respond with the original imageif (accept && accept.includes('image/webp')) {option.eo.image.format = 'webp';}const response = await fetch(request, option);return response;}addEventListener('fetch', event => {// When the function code throws an unhandled exception, the Edge function transmits the request back to the originevent.passThroughOnException();event.respondWith(handleEvent(event));});
Example Preview
Enter the URL that matches the triggering rules of the Edge function in the address bar of the browser on the PC side and mobile side (e.g.,
https://example.com/images-format/ef-1.jpeg
), and the image will be automatically converted to Webp format.![](https://cloudcache.intl.tencent-cloud.com/cms/backend-cms/73a4ecae76f111eeb5cb52540099b6dd.png)
Related References