Cashed

Cash rules everything around me, C.R.E.A.M! Get the money, dolla dolla bill ya'll

Cashed is an in memory compress once serve many times static file server with propper support for Etags and 304 responses.

Why?

Compressing static resources is an imporant optimization for serving resources as fast as possible. The problem with compression in node.js is that it's a CPU bound activity, meaning while the asset is being compressed the event loop is temporarily blocked. Also, it just doesn't make sense to have to compress the same resource every time it's requested as the same result will be produced every time.

What's the magic?

When a request is received for a static resource by cashed and we don't have a matching file/compression-algo payload stashed in memory we generate one and push the results through the response stream and stash them in memory as well. So all subsequent requests for the same static resource will be served pre-compressed and directly from memory. Cashed currently supports Gzip and Deflate compression algorithms and caches them both independently.

As a free side effect of using filed we also get Etag based caching for free. When an Etag cache it is detected by cashed the resulting HTTP payload the HTTP client will receive in the 304 response is typically ~53 bytes, because the resource doesn't have to be sent to the client, just some cache hit headers and the 304 status code.