Re: httpd cache in wsx
- From: "Neil Smith [MVP Digital Media]" <neil@xxxxxxxxxx>
- Date: Wed, 01 Aug 2007 21:54:16 GMT
On Wed, 01 Aug 2007 09:27:45 +0200, Haris Zukanovi? <haris@xxxxxx>
wrote:
Hi ppl,
I have following content_137.wsx on my streaming server
<?wsx version="1.0"?>
<smil>
<media
src="httpd://backend/backend.php/content/stream/id/137/%QueryString%"/>
</smil>
Everything works ok, but after a while (which can also be days, but can
also be hours) when I try to stream, WMS suddenly decides it will not
longer request the dynamic source
src="httpd://backend/backend.php/content/stream/id/137/%QueryString%"/>
and seems like it is using some cached version of this response
I have verified this by tailing the logs of backend webserver, no
request is recorded when this happends.
The script at httpd://backend/backend.php/content/stream/id/137/ is
configured to respond with no-cache headers, here they are:
REPONSE: HTTP/1.0 200 OK
Date: Wed, 01 Aug 2007 13:24:02 GMT
Server: Apache/2.2.3 (Ubuntu) PHP/5.2.1
X-Powered-By: PHP/5.2.1
Cache-Control: no-store, no-cache, must-revalidate, post-check=0,
pre-check=0,
Pragma: no-cache,
Etag: 6ee0731be4cc838013bbcd42af96a5be
Content-Length: 207
Connection: close
Content-Type: text/html; charset=utf-8
Any ideas?
Where would I check to verify this theory?
It's going to be hard to diagnose if it's an intermittent problem.
Once it definitely fails, you might be able to use Fiddler http proxy
running on the server to debug the request and response.
http://www.fiddler2.com/Fiddler2/version.asp
Does the ETag always change ? It should be distinct (eg an MD5) for
any change in the content response, or the httpd plugin really might
cache the response if it sees the same ETag. it's used by IE, and
presumably WinInet, where Firefox I think uses the last-modified
header).
You're not sending last-modified at all, but if it's truly dynamically
generated, it probably should have that header. That will be relevant
for HTTP1.1, it looks above like the media server requested using
HTTP1.0 (which is the same as the media encoder http server delivers)
There's a discussion of the subtleties of cacheing based on
last-modified, if-modified-since and other similar headers here :
http://fishbowl.pastiche.org/2002/10/21/http_conditional_get_for_rss_hackers
In your example above, you seem to be sending text/html content type
(default for PHP), perhaps you could try one of video/x-ms-asf ,
application/smil or application/xml instead just to be sure.
I also noticed a trailing comma on your Pragma: no-cache,
which is probably unrelated but should be fixed up.
HTH
Cheers - Neil
------------------------------------------------
Digital Media MVP : 2004-2007
http://mvp.support.microsoft.com/mvpfaqs
.
- Follow-Ups:
- Re: httpd cache in wsx
- From: Haris Zukanovic'
- Re: httpd cache in wsx
- References:
- httpd cache in wsx
- From: Haris Zukanović
- httpd cache in wsx
- Prev by Date: httpd caching in wsx?
- Next by Date: Re: httpd cache in wsx
- Previous by thread: httpd cache in wsx
- Next by thread: Re: httpd cache in wsx
- Index(es):
Relevant Pages
|
Loading
