It’s probably better to export the photos if you want to make a public presentation gallery. Many image viewers can create static HTML pages for a given set of images, GThumb, DigiKam etc. But it could work with a photo management app too if it has presentation gallery support and can be configured to serve images from a CDN prefix.

The catch with CDN support in dynamic apps is that they need to be aware that you want to use a CDN so they can provide both a dynamic view (of whatever resource you’re trying to cache) so you have something to pull the original from, as well as use the CDN URL for their main pages so they take advantage of the caching.

Alternatively, if they don’t have CDN support, or you want to isolate the dynamic app from the public, if the app makes good static-looking URLs you can scrape it, make static pages and upload that to the CDN.

I recently did this for someone who was using a gallery app that was made with super old MySQL and PHP versions and was super unsafe and inefficient. I used URL-rewriting to make all pages end in .html and .jpg, then scraped it with wget, uploaded the whole thing to CDN and pointed a CNAME of their domain to the CDN domain. The dynamic app now lives on a private server in docker containers which they access over VPN, and when they change stuff I just run a script that takes a new snapshot and uploads it to the CDN.