my question seems duplicate of this
but I am having a case
when I refresh a page with F5 then images are not getting fetched from cache instead request is going to server and server responding 304 status code(not modified)
but if I type a URL in address-bar or navigate page from browser back/forward button then images are coming from cache.
but I am having one doubt here why request is made for cached images to origin server on F5 (page refresh)
Nginx configuration
location ~* \.(js|css|png|jpg|jpeg|gif|ico)$ {
expires 2d;
proxy_pass http://localhost:3001;
break;
}
Request header
===================================
GET /assets/first_banner.png HTTP/1.1
Host: localhost:3000
Connection: keep-alive
Cache-Control: no-cache
Pragma: no-cache
Accept: image/webp,*/*;q=0.8
User-Agent: Mozilla/5.0 (X11; Linux i686) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.65 Safari/537.36
Referer: http://localhost:3000/
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
===================================
Response header:
===================================
HTTP/1.1 200 OK
Server: nginx/1.1.19
Date: Sun, 08 Dec 2013 20:31:06 GMT
Content-Type: image/png
Content-Length: 141498
Connection: keep-alive
Cache-Control: max-age=172800
Last-Modified: Wed, 23 Oct 2013 05:34:11 GMT
Etag: "0fc96d0218a47398d37dacca76916727"
X-Ua-Compatible: IE=Edge
X-Request-Id: 48d1ec3a24e2c0f13250ea74101f6753
X-Runtime: 0.021479
Expires: Tue, 10 Dec 2013 20:31:06 GMT
===================================
When you hit F5 you tell the browser to check the webserver if the content, cached locally or not, is still valid.
If the object is expired on the webserver then the browser fetch the asset again. If the object is still valid, the local browser-cached content is used.
Related
I am trying to create a cron job to access a particular URL to do some maintenance stuff. While accessing the URL remotely from Chrome works fine (returns 200 OK), accessing it locally on the server with wget gets me "ERROR 503: Service Unavailable."
root#domain:/home/admin/web/domain.com/public_html/# wget http://www.domain.com/index.php?route=module/marketplace&action=run_queue
[1] 30283
root#domain:/home/admin/web/domain.com/public_html/# --2016-09-06 16:02:42-- http://www.domain.com/index.php?route=module/marketplace
Resolving www.domain.com (www.domain.com)... 46.10.20.30
Connecting to www.domain.com (www.domain.com)|46.10.20.30|:80... connected.
HTTP request sent, awaiting response... 503 Service Unavailable
2016-09-06 16:02:42 ERROR 503: Service Unavailable.
I am using Apache/2.4.7 (Ubuntu) + Nginx for serving static files.
Headers sent by Chrome
GET /index.php?route=module/marketplace&action=run_queue HTTP/1.1
Host: www.domain.com
Connection: keep-alive
Pragma: no-cache
Cache-Control: no-cache
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
DNT: 1
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8,ro;q=0.6
Cookie: cookieconsent_dismissed=yes; __tawkuuid=e::domain.com::qsV03tUWg5avl3mTmLetAJpcbS+TGvpb7L33ER0ooHvJ0wsAPilIfGadi5f::2; Tawk_55ec3df37d21121ad0a5a=vs16.tawk.to:443::0; currency=USD; __atuvc=10%7C34; PHPSESSID=foru997tgbo437je6djtd3c2; language=ro; _ga=GA1.2.13206174.14484999; TawkConnectionTime=0; language=ro; currency=RON
Headers received in Chrome
HTTP/1.1 200 OK
Server: nginx
Date: Tue, 06 Sep 2016 13:22:23 GMT
Content-Type: text/html
Content-Length: 0
Connection: keep-alive
Keep-Alive: timeout=10
X-Powered-By: PHP/5.5.9-1ubuntu4.19
Expires: Thu, 19 Nov 1981 08:52:00 GMT
Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
Pragma: no-cache
What might be the problem here?
It was the comment of Margaret Bloom below my question which solved my problem. It was in fact an authentication problem and once I had the website correctly configured to be publicly accessible, wget started working normally.
It was initially working in Chrome because I was authenticated there.
Thanks.
I want to use ETag to cache the version of a request and return 304 not modifed response to the client so the client can use last cached page.
So my url is like this which returns a json response
"http://server/WEB_GWT/prmCall?prmName=PRM_SIS_PROG_REG_STATUS"
In my servlet handling this request, I am always putting ETag information to store its value to be the version of url param PRM_SIS_PROG_REG_STATUS.
So response header returning to client is
HTTP/1.1 200 OK
Date: Sat, 07 Dec 2013 16:07:49 GMT
Server: IBM_HTTP_Server
ETag: "5"
Last-Modified: Sat, 07 Dec 2013 16:07:49 GMT
Content-Length: 356
Keep-Alive: timeout=10, max=99
Connection: Keep-Alive
Content-Type: application/json
Content-Language: tr-TR
In my next request, I am expecting this request header to include "If-None-Match" header to return the version of the request but I cannot get this header param. Any idea why I cannot get my ETag back.
My next request header is
GET /OZU_GWT/prmCall?prmName=PRM_SIS_PROG_REG_STATUS HTTP/1.1
Host: 10.100.199.103
Connection: keep-alive
Cache-Control: max-age=0
If-Modified-Since: Thu, 01 Jan 1970 00:00:00 GMT
User-Agent: Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.57 Safari/537.36
Accept: */*
Referer: http://10.100.199.103/OZU_GWT/
Accept-Encoding: gzip,deflate,sdch
Accept-Language: tr-TR,tr;q=0.8,en-US;q=0.6,en;q=0.4
Cookie: JSESSIONID=0000kvocMBmjoWPbpKt_VAsDUMv:-1
Inoder to cache your request you need to include "Cache-Control" directive and specify the way in which the response should be cached and for what period.
HTTP/1.1 200 OK
Date: Sat, 07 Dec 2013 16:07:49 GMT
Server: IBM_HTTP_Server
ETag: "5"
Cache-Control : public, max-age=86400
Content-Length: 356
Keep-Alive: timeout=10, max=99
Connection: Keep-Alive
Content-Type: application/json
Content-Language: tr-TR
Here the Cache-Control header says that the content can be stored by "public" caching servers and the duration after which it needs to revalidate the content is 86400 seconds. And so when you refresh the page again "If-None-Match" and "If-Modified-Since" conditional headers will kick in and use the cached data.
After some investigation,I found out SmartGWT framework requests are sent to server with bypassCache:true flag which was sending my xhr request without any cache header. I managed to fixed it by overriding following method in DataSource class.
#Override
protected Object transformRequest(DSRequest dsRequest) {
dsRequest.setBypassCache(false);
I am trying to make a REST call using chrome DHC and Advanced rest clients. For example:
A HEAD call to http://www.google.co.in
using advanced REST client gives:
Redirect To:https://www.google.co.in/ with status: 302 Show explanation HTTP/1.1 302 Found
Redirection information has not been cached.
Location: https://www.google.co.in/
Cache-Control: private
Content-Type: text/html; charset=UTF-8
Date: Fri, 29 Nov 2013 06:57:46 GMT
Server: gws
X-XSS-Protection: 1; mode=block
X-Frame-Options: SAMEORIGIN
Alternate-Protocol: 80:quic
Content-Length: 222
Proxy-Connection: Keep-Alive
Connection: Keep-Alive
Status
200 OK Show explanation Loading time: 764
Request headers
Accept: application/json
Accept-Language: en-US
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/31.0.1650.57 Safari/537.36
X-Chrome-Variations: <some value>
Accept-Encoding: gzip,deflate,sdch
Cookie: <some value>
Response headers
status: 200 OK
version: HTTP/1.1
alternate-protocol: 443:quic
cache-control: private, max-age=0
content-encoding: gzip
content-length: 34821
content-type: text/html; charset=UTF-8
date: Fri, 29 Nov 2013 06:57:46 GMT
expires: -1
server: gws
x-frame-options: SAMEORIGIN
x-xss-protection: 1; mode=block
I am more interested on details of request header as "Accept-Charset" is not recognized. If i give anything as header it is atleast displayed in request header. Now some questions:
why this is not recognized? is this client problem or server problem? do i need to use any other client. I am not aware.
If it is recognized then I should be able to validate this value in server code, which in my case is running in jetty?
Thanks,
Akhi
I found that its a client problem, specific to Chrome. I dont know why with chrome this header is completely ignored.
When i tried to send http request using CURL command, i was able to retrieve this header. Now i can go ahead with validation of "Accept-Charset" header.
I've read all the caching documentation for HTTP, and this are the headers for my file:
Edit: I am now using amazon S3 to see if it helps and still the same problem! Here go the request and the response> What am I missing? Even thought the response asks for the browser to cache the file, it doesn't! I've checked the Google Chrome cache and the file is not there.
Request URL:https://s3-sa-east-1.amazonaws.com/combo-combat-release/WebPlayer.unity3d
Request Method:GET
Status Code:200 OK
**Request Headers**
GET /combo-combat-release/WebPlayer.unity3d HTTP/1.1
Host: s3-sa-east-1.amazonaws.com
Connection: keep-alive
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.17 (KHTML, like Gecko) Chrome/24.0.1312.52 Safari/537.17
Accept: */*
Accept-Encoding: gzip,deflate,sdch
Accept-Language: es,en-US;q=0.8,en;q=0.6
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
**Response Headers**
HTTP/1.1 200 OK
x-amz-id-2: xu/RKgR4Xt6G3jQ1qkdO5rzd4TlngDYYERZ+bbGlalitJFMDjAgiLAoP4GXhmkeo
x-amz-request-id: 6A9389D16407D28D
Date: Wed, 16 Jan 2013 22:42:26 GMT
Cache-Control: max-age=2592000, public, must-revalidate
Last-Modified: Wed, 16 Jan 2013 22:29:55 GMT
ETag: "0f8d22257da9fcae61f21fd30b7a1fd4"
Accept-Ranges: bytes
Content-Type: application/octet-stream
Content-Length: 39222189
Server: AmazonS3
But the browser doesn't cache the file. Each time, the request is sent and all the data transferred from scratch (200 OK instead of 304). :(
File size is 37.4 MB
Any tip on what could be wrong?
Thanks,
Manuel
Try HTTP 1.1 instead of 1.0.
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html states:
Note that HTTP/1.0 caches might not implement Cache-Control and
might only implement Pragma: no-cache
When pages on our website are updated and we load them in the browser they are never reloaded (until I explicitly refresh).
The first time I load Chrome Developer Tools just says "(from cache)" and doesn't show any headers but I reckon they should always send a request to validate the ETag. Or maybe the server sends a 304 Not Modified response status in error but this doesn't show up in the Network tab.
When I refresh, these are the headers. Anyone sees what is wrong?
Request
GET /home/index.html HTTP/1.1
Host: *******.be
Connection: keep-alive
Cache-Control: max-age=0
User-Agent: Mozilla/5.0 (Windows NT 6.1) AppleWebKit/536.5 (KHTML, like Gecko) Chrome/19.0.1084.56 Safari/536.5
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Referer: http://*****.be/home/index.html
Accept-Encoding: gzip,deflate,sdch
Accept-Language: nl-NL,nl;q=0.8,en-US;q=0.6,en;q=0.4
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3
If-None-Match: "c38f300d-114d-4c2565b57b420"
If-Modified-Since: Wed, 13 Jun 2012 08:27:42 GMT
Response
HTTP/1.1 304 Not Modified
Date: Wed, 13 Jun 2012 11:24:52 GMT
Server: Apache
Connection: close
ETag: "c38f300d-114d-4c2565b57b420"
I have tested this with Chrome 19 and IE9.