How to set cache ttl for static assets with workers sites?

When i test my site with pagespeed, all the images have no cache ttl set.

how do i do it?

Is there any type of headers sections for those images in the Workers script? You can add this in with the other image headers:

      'cache-control': 'max-age=31536000',

where can i find it?

i just follow the tutorial to deploy a jekyll site https://developers.cloudflare.com/workers/sites/start-from-existing/

In dash.cloudflare.com, click on the Workers link in the right column and find your site’s script. Then click “Quick Edit” and comb through the code.