README.md

20_ssr-cache-proxy

Running mode :

astro starts with pnpm run preview listens on port 4000
express starts with pnpm run proxy listens on port 3000
first client page load from proxy : cache miss, proxy fetches data from SSR
SSR generates the page and and on creation assigns a page hash
for the example purpose a 2 seconds timeout is added to a page render
the page hash is updated on the proxy (in the example through a shared hashes.json but could be with a db or API)
when the proxy fetches the page it identifies the cached page with its hash (as it is always actual on the hashes.json)
follow up request checks if page is available and if hash is fresh
when the user updates the data, the server updates the page hash
follow up requests on the proxy show the page to be stale due to old cached page, the proxy fetches the page with the new hash