[Zope] IE caching issues
sam gendler
sgendler@akamai.com
Sat, 17 Mar 2001 01:34:05 -0800
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How close are they to the zope server. If they are connecting through an ISP
or something, it is possible that the ISP has a cache between them Zope,
transparently intercepting traffic. See if the Server line is changed in a
response, or see if there is a Via header added (use a utility that will show
you http headers, like ab or curl). If there is a transparent cache, you can
ask your ISP to exempt you (assuming it is your ISP and not some cache in the
middle of the internet somewhere), or else you can try to work around it.
The browser reload process should be sending no-cache requests or
if-modified-since ones, so your only recourse is to make the objects
themselves uncacheable, including the management pages, otherwise the cache
might cache the management pages, even if the results of the rendered page
are not cachable. I would look around in the ZServer and see where it
constructs the http response, and force it to send 'Cache-Control: no-cache,
max-age=0, private' and 'pragma: no-cache' on every single page it sends.
One of those should work on every cache I have ever seen, from many years ago
to the present. Don't worry about pages that send these headers as well. It
is legal to send the same header twice. You will still have to wait a while
for the cached versions to timeout o any network cache, before this solution
will work.
--sam
kosh wrote:
> Not sure if this is a zope issue or not. I have some people doing work on
> a site developed in zope however ie is often showing the wrong version of
> the page. I followed the caching instructions in
> http://www.zope.org/Members/htrd/howto/caching and it works on every
> browser except ie. I have checked and they have set the browser to check
> on every page view however often it does not even hit the webserver. I
> have had them hit reload while watching server logs and no connect was
> attempted. I then tried it in vmware using nt 4 with ie 5.5 and it does
> the same thing also. Even when the cache is deleted on ie and it is told
> to run with no cache it seems to cache the documents somehow. It seems the
> only solution is rebooting windows on their machine which is not a good
> one or using some version of netscape.
>
> If someone knows why this is happening I would really like to get it
> solved. If I could get away with having no ie support I would but alas
> that is not an option I have. :(
>
> _______________________________________________
> Zope maillist - Zope@zope.org
> http://lists.zope.org/mailman/listinfo/zope
> ** No cross posts or HTML encoding! **
> (Related lists -
> http://lists.zope.org/mailman/listinfo/zope-announce
> http://lists.zope.org/mailman/listinfo/zope-dev )
--
------------------------------------------
"There are two rules for success:
1. Never tell everything you know.
--Roger H. Lincoln
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How close are they to the zope server. If they are connecting through
an ISP or something, it is possible that the ISP has a cache between them
Zope, transparently intercepting traffic. See if the Server line
is changed in a response, or see if there is a Via header added (use a
utility that will show you http headers, like ab or curl). If there
is a transparent cache, you can ask your ISP to exempt you (assuming it
is your ISP and not some cache in the middle of the internet somewhere),
or else you can try to work around it.
<p>The browser reload process should be sending no-cache requests or if-modified-since
ones, so your only recourse is to make the objects themselves uncacheable,
including the management pages, otherwise the cache might cache the management
pages, even if the results of the rendered page are not cachable.
I would look around in the ZServer and see where it constructs the http
response, and force it to send 'Cache-Control: no-cache, max-age=0, private'
and 'pragma: no-cache' on every single page it sends. One of those
should work on every cache I have ever seen, from many years ago to the
present. Don't worry about pages that send these headers as well.
It is legal to send the same header twice. You will still have to
wait a while for the cached versions to timeout o any network cache, before
this solution will work.
<p>--sam
<p>kosh wrote:
<blockquote TYPE=CITE>Not sure if this is a zope issue or not. I have some
people doing work on
<br>a site developed in zope however ie is often showing the wrong version
of
<br>the page. I followed the caching instructions in
<br><a href="http://www.zope.org/Members/htrd/howto/caching">http://www.zope.org/Members/htrd/howto/caching</a>
and it works on every
<br>browser except ie. I have checked and they have set the browser to
check
<br>on every page view however often it does not even hit the webserver.
I
<br>have had them hit reload while watching server logs and no connect
was
<br>attempted. I then tried it in vmware using nt 4 with ie 5.5 and it
does
<br>the same thing also. Even when the cache is deleted on ie and it is
told
<br>to run with no cache it seems to cache the documents somehow. It seems
the
<br>only solution is rebooting windows on their machine which is not a
good
<br>one or using some version of netscape.
<p>If someone knows why this is happening I would really like to get it
<br>solved. If I could get away with having no ie support I would but alas
<br>that is not an option I have. :(
<p>_______________________________________________
<br>Zope maillist - Zope@zope.org
<br><a href="http://lists.zope.org/mailman/listinfo/zope">http://lists.zope.org/mailman/listinfo/zope</a>
<br>** No cross posts or HTML encoding! **
<br>(Related lists -
<br> <a href="http://lists.zope.org/mailman/listinfo/zope-announce">http://lists.zope.org/mailman/listinfo/zope-announce</a>
<br> <a href="http://lists.zope.org/mailman/listinfo/zope-dev">http://lists.zope.org/mailman/listinfo/zope-dev</a>
)</blockquote>
<pre>--
------------------------------------------
"There are two rules for success:
1. Never tell everything you know.
--Roger H. Lincoln</pre>
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