Assetproxy is a HTML rewriting proxy that makes sure that no 3rd party asstes are served on your website. When it finds an asset served from a third-party domain, it caches it and rewrites its URL in HTML so it points to your main domain. The rewritten URLs are signed with a server-stored secret, so only content that has been originally in your HTML will be cached server-side.
It shares significant portion of the code with Configurable HTML Rewriter
Sealhub project: Assetproxy
Code repository: Assetproxy · asset-proxy