Hello, I'm using Go's standard library reverse proxy and I'm trying to figure out if the standard library HTTP web server (e.g. http.ListenAndServe) implements the relevant conditional request handling logic for ETag/Last-Modified headers.
I did some Googling and noticed the HTTP file system request handler (https://golang.org/src/net/http/fs.go) does implement that logic, but I couldn't find the same for the HTTP web server. I also couldn't find any examples of setting ETags/Last-Modified (other than this basic implementation for setting ETags: https://github.com/go-http-utils/etag/blob/master/etag.go). What's confusing me there is the concept of "strong" and "weak" validation and how certain scenarios might influence whether an ETag is marked as either strong or weak (depending on the implementation -- see https://developer.mozilla.org/en-US/docs/Web/HTTP/Conditional_requests#Validators). So to recap, my questions are (and I appreciate some of these are outside the scope of just Go -- so apologies if that's not allowed in this forum): 1. Should I set ETag/Last-Modified in a proxy? Last-Modified feels like it's not the responsibility of the proxy but the origin, where as an ETag is something I feel is "ok" to do in the proxy as a 'fallback' (as we already set 'serve stale' caching headers on behalf of our origins if they neglect to include them). 2. Do I need to implement `If-None-Match` and `If-Modified-Since` behaviours myself (i.e. is it not provided by the Go standard library's HTTP web server)? 3. I was planning on setting an ETag header on the response from within httputil.ReverseProxy#ModifyResponse but wasn't sure if that would be the correct place to set it. 4. What constitutes a strong/weak validator (e.g. would a simple hash function generating a digest of the URL path + response body suffice)? Thanks for any help/insights/opinions y'all can share with me. Kind regards, Mark -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/b9428dbf-55d7-4ae2-ab11-523f94102071%40googlegroups.com.
