Hi, On 29/03/2016 20:23, intrigeri wrote: >> Should we add "Cache-Control" and "ETag", and remove "Expires"? > I don't know. I'll look into it later this week. > >> $ wget --server-response >> https://tails.boum.org/install/v1/Tails/i386/stable/latest.yml >> --2016-03-29 18:06:06-- >> https://tails.boum.org/install/v1/Tails/i386/stable/latest.yml >> Resolving tails.boum.org (tails.boum.org)... 204.13.164.188 >> Connecting to tails.boum.org (tails.boum.org)|204.13.164.188|:443... >> connected. >> HTTP request sent, awaiting response... >> HTTP/1.1 200 OK >> Date: Tue, 29 Mar 2016 18:06:08 GMT >> Server: Apache/2.2.22 (Debian) >> X-Frame-Options: SAMEORIGIN >> X-XSS-Protection: 1; mode=block >> X-Content-Type-Options: nosniff >> Strict-Transport-Security: max-age=15768000 >> Last-Modified: Fri, 18 Mar 2016 20:43:59 GMT >> Accept-Ranges: bytes >> Content-Length: 269 >> Cache-Control: max-age=0 >> Expires: Tue, 29 Mar 2016 18:06:08 GMT >> Keep-Alive: timeout=15, max=100 >> Connection: Keep-Alive >> Content-Type: text/plain >> Content-Language: en >> Length: 269 [text/plain] >> Saving to: ‘latest.yml’
I believe that Cache-control: max-age=0 header, which appears to be already there, actually causes the browser to revalidate every time, therefore producing an additional hit, even if the response for unchanged files is a body-empty "304 Not Modified". Both "max-age" and Expire should reflect your expectation of how long the IDF is likely to remain valid (1 day? 1 week? 1 month?). Using ETag is just an alternate way to reduce the network traffic, by giving the revalidating server another way to tell whether the IDF is stale other than If-Not-Modified-Since, i.e. If-None-Match, but won't reduce the validation hits: that's a job for Cache-Control and Expire. Disclaimer: I'm not a caching guru, but this resource may help https://www.mnot.net/cache_docs/ Cheers -- G -- Giorgio Maone https://maone.net _______________________________________________ Tails-dev mailing list Tails-dev@boum.org https://mailman.boum.org/listinfo/tails-dev To unsubscribe from this list, send an empty email to tails-dev-unsubscr...@boum.org.
