Any ideas why on some links that I try to access using HttpWebRequest I am getting "The remote server returned an error: (304) Not Modified." in the code? The code I'm using is from Jeff's post he...

I'm trying to tell nginx to cache some of my assets (js, css) forever, or at least for a very long time. The idea is that once an asset bundle is compiled and published with an /assets/ URI prefix...

I want browsers to always add (except first time) "If-Modified-Since" request header to avoid unnecessary traffic. Response headers are: Accept-Ranges:bytes Cache-Control:max-age=0, must-revalida...

Expressjs automatically send etags. I would like to know how the etag is generated..is it based on the content that is generated dynamically by the get routine. or is there way I can mainpulate it,...

I've found that Edge doesn't work when playing videos for the 2nd time. My app is using a default <video> tag and Edge is sending an If-Modified-Since header when it loads the video for the s...

When I generate a page I send headers HTTP/1.1 200 OK Cache-Control: private Content-Type: text/html; charset=utf-8 Last-Modified: Mon, 04 Apr 2011 20:08:33 GMT Vary: Accept-Encoding Date: Mon, 11...

In my python application I have to read many web pages to collect data. To decrease the http calls I would like to fetch only changed pages. My problem is that my code always tells me that the page...

I am attempting to issue an Http Get request from a windows universal app and seeing an odd behavior. (not sure if the fact that it is a universal app is related or not). The simplified code in qu...

I want to implement a "get changed values" capability in my API. For example, say I have the following REST API call: GET /ws/school/7/student This gets all the students in school #7. Unfortunat...

I'm trying to use HTTP "If-Modified-Since" header. My server responds to every HTTP request with "Last-Modified" header. When the client sends the same request again, it updates the "If-Modified-...

I have a PHP script which is called with an ?img= parameter. The value for that parameter is an (urlencoded) URL of an image. My script checks, if that image is already stored at my server. If n...

My Browser isn't sending back an If-Modified-Since Header for PHP generated Content on the first request my script sends: (Status-Line) HTTP/1.1 200 OK Date Thu, 21 Jan 2010 08:55:25 GMT Server A...

I have a page with lots of small images (icons). When used with chrome, each time the page is reloaded, chrome requests each icon from the server with if-modified-since header. All icons are serve...

I'm serving a dynamically created recent.rss via python flask and naturally that way it is always sent via 200 OK. I was going to fix this by setting the header Expires a week into the future and c...

I am looking at a Caching library that is trying to use the If-Modified-Since header of a request object. The problem is this header never gets set, it is always blank which makes sense to me seein...

There seems to be a problem between how PHP engine handles identical files that differ only in their file extension. Problem: "An If-Modified-Since conditional request returned the full conten...

As far as I understand the specs, the ETag, which was introduced in RFC 2616 (HTTP/1.1) is a successor (of sorts) for the Last-Modified-Header, which is proposet to give the software-architect more...

There seem to be two distinct ways to implement conditional requests using HTTP headers, both of which can be used for caching, range requests, concurrency control etc...: If-Unmodified-Since and...