if-modified-since

If-Modified-Since not considered while using httr GET?

由 拥有回忆 提交于 2019-12-12 05:09:27
问题 My requirement/objective: I'm retrieving Facebook posts for the past 3 months from a public page, and I would like to select only those posts which have been modified in the recent past (in the last 2 days). I'm using httr R package, and using the GET function to accomplish the above. I tried the following : url.data <- GET(url, config(token=token), config(add_headers("If-Modified-Since" = "2016-09-08 11:45"))) url.data <- GET(url, config(token=token, add_headers("If-Modified-Since" = "2016

System.Net.Http.HttpClient adding If-Modified-Since header

由 流过昼夜 提交于 2019-12-11 09:52:25
问题 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 question is this: var client = new HttpClient(); var response = await client.GetAsync("https://storage.googleapis.com/pictureframe/settings.json"); var s = await response.Content.ReadAsStringAsync(); In a unit test or console app that works as expected and the variable s contains the json content.

How to make Safari send if-modified-since header?

由 不羁的心 提交于 2019-12-11 01:26:13
问题 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 Apr 2011 01:36:21 GMT Content-Length: 3019 then, when I try to get this page again all browsers send correct request and get 304 answer except Safari - it never sends if-modified-since. It always reloads whole page even it havnt been changed Does this behavior of Safari known and what to do to make

What response should If-Modified-Since HTTP Header return if request is HEAD?

由 ℡╲_俬逩灬. 提交于 2019-12-07 10:13:36
问题 If you send a GET request with an If-Modified-Since header, the server suports it and the file hasn't changed, the server will return a 304 response. If you sent a HEAD request in the same circumstances, should the server send a 304 response or send back the full headers you would have sent had the file changed? In short: is GET / HEAD equivalent when requesting a file that has not changed? 回答1: As per RFC The HEAD method is identical to GET except that the server MUST NOT return a message

Indefinitely caching a HTTP response via Nginx fails

由 六眼飞鱼酱① 提交于 2019-12-06 10:54:52
问题 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 (e.g. /assets/foo-{fingerprint}.js ) it stays there and doesn't ever need to change. The internets told me I should write the following rule: location ~ ^/assets/.*-([^.]+)\.(js|css)$ { gzip_static on; # there's also a .gz of the asset expires max; add_header Cache-Control public; add_header Last

What response should If-Modified-Since HTTP Header return if request is HEAD?

由 时光总嘲笑我的痴心妄想 提交于 2019-12-05 12:39:40
If you send a GET request with an If-Modified-Since header, the server suports it and the file hasn't changed, the server will return a 304 response. If you sent a HEAD request in the same circumstances, should the server send a 304 response or send back the full headers you would have sent had the file changed? In short: is GET / HEAD equivalent when requesting a file that has not changed? As per RFC The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response. The metainformation contained in the HTTP headers in response to a HEAD request SHOULD

(Weak) ETags and Last-Modified

由 ￡可爱￡侵袭症＋ 提交于 2019-12-03 07:56:25
问题 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 controll over the cache-revalidating process. If both Cache-Validation-Headers (If-None-Match and If-Modified-Since) are present, according to RFC 2616, the client (i.e. the browser) should use the ETag when checking, if a resource has changed. According to section 14.26 of RFC 2616, the server

(Weak) ETags and Last-Modified

由 天大地大妈咪最大 提交于 2019-12-02 20:38:14
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 controll over the cache-revalidating process. If both Cache-Validation-Headers (If-None-Match and If-Modified-Since) are present, according to RFC 2616, the client (i.e. the browser) should use the ETag when checking, if a resource has changed. According to section 14.26 of RFC 2616, the server MUST NOT respond with a 304 Not Modified, if the ETag presented in a If-None-Match-Header has changed, and

how does a etag work in expressjs

由 末鹿安然 提交于 2019-11-30 02:42:56
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, by not even going through the process of generating the content(dynamic content - from DB) and pass back etag as same. may be a middleware which start with just checking if it is valid session id and pass back the same etag that the client gives or may be based of the url + session id..that way it will be unique. and end the request there rather going through the whole db call and all those stuff.

Understand If-Modified-Since HTTP Header

由 空扰寡人 提交于 2019-11-28 23:26:46
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 seeing how it is a REQUEST. How can you force a request to have a If-Modified-Since header? Or am I way off for what this does. Here is the function I am referring to. public function isNotModified(Request $request) { $lastModified = $request->headers->get('If-Modified-Since'); $notModified = false; if ($etags = $request->getEtags()) { $notModified = (in_array($this->getEtag(), $etags) || in_array('*',
订阅 if-modified-since