httpcache

httpcache provides an rfc7234 compliant golang http.Handler.

Example

This example if from the included CLI, it runs a caching proxy on http://localhost:8080.

proxy := &httputil.ReverseProxy{
    Director: func(r *http.Request) {
    },
}

handler := httpcache.NewHandler(httpcache.NewMemoryCache(), proxy)
handler.Shared = true

log.Printf("proxy listening on http://%s", listen)
log.Fatal(http.ListenAndServe(listen, handler))

Implemented

• All of rfc7234, except those listed below
• Disk and Memory storage
• Apache-like logging via httplog package

Todo

• Offline operation
• Size constraints on memory/disk cache and cache eviction
• Correctly handle mixture of HTTP1.0 clients and 1.1 upstreams
• More detail in Via header
• Support for weak entities with If-Match and If-None-Match
• Invalidation based on Content-Location and request method
• Better handling of duplicate headers and CacheControl values

Caveats

• Conditional requests are never cached, this includes Range requests

Testing

Tests are currently conducted via the test suite and verified via the CoAdvisor tool.

Reading List

• http://httpwg.github.io/specs/rfc7234.html
• https://www.mnot.net/blog/2011/07/11/what_proxies_must_do
• https://www.mnot.net/blog/2014/06/07/rfc2616_is_dead