[Zope] Help with session data and redirects
Brad Powell
Brad.Powell@conocophillips.com
Tue, 15 Apr 2003 11:06:04 -0500
This is a multipart message in MIME format.
------=_NextPartTM-000-b09ecce5-c437-476b-9d74-66dfd231bba6
Content-Type: multipart/alternative;
boundary="=_alternative 0058719686256D09_="
--=_alternative 0058719686256D09_=
Content-Type: text/plain; charset="us-ascii"
Thanks, Chris, for the quick reply. I tried both of your suggestions: the
random query string and the setHeader statements in the ZPT. They both
improved the situation in that requests after the initial one are now
returned properly. However, the very first request still returns the "Problem: no session object (redirectTest)" message. By the way, instead of a response.redirect, if I return the page
template directly in the script with a statement like "return
container['view_session_obj.pt']()", it works perfectly. Unfortunately, I
need the redirect because of the way my actual page template works.
Brad
Chris McDonough <chrism@zope.com>
04/15/2003 10:18 AM
To: Brad Powell/PPCO@Phillips
cc: zope@zope.org
Subject: Re: [Zope] Help with session data and redirects
Under Mozilla 1.3 on Linux, when running your test (e.g. when visiting
/createSessionAndRedirect?sessionText=456), I immediately get:
## Page Template "view_session_obj.pt" ##
456
Like you, I suspect this may be a browser issue.
To verify, cause the createSessionAndRedirect to generate a "random"
query string like this:
session = context.REQUEST.SESSION
sessionObjName = 'redirectTest'
session.set(sessionObjName, sessionText)
return
context.REQUEST.RESPONSE.redirect(context["view_session_obj.pt"].absolute_url()
+ '?abc=%s' % context.ZopeTime().timeTime())
This should prevent browsers from returning a cached page. A more
permanent solution would be to set a Pragma: No-Cache or Cache-Control:
No-Cache HTTP header within "view_session_obj.pt".
- C
On Tue, 2003-04-15 at 10:58, Brad Powell wrote:
> I have a problem where session data does not appear to be updated when
the
> setting of the session data is followed by a response.redirect in a
Python
> script. A browser refresh is required to get the correct data
displayed.
> This happens on both Zope v2.5.1 and v2.6.1. It also happens with IE
and
> Mozilla browsers; but, interestingly, it does not occur with the
Konqueror
> browser. This led me to believe it was a browser issue, but no matter
> what options I try in IE, I cannot get it to work. I thought it might
be
> an issue with the browser cache settings, but, again, no matter what I
try
> I get the same result.
>
> I've included a test script and page template that demonstrates this
> problem. When I go to url "sessionCreateAndRedirect?sessionText=123", I
> get the message, "Problem: no session object (redirectTest)." If I then
> refresh the browser, I get "123" displayed, which is the correct
response.
> Subsequent calls to the url with different values for sessionText
returns
> the previous session value, until I do a browser refresh.
>
> Any assistance, guidance, wisdom, etc. on this matter would be greatly
> appreciated.
>
>
> ## Script (Python) "sessionCreateAndRedirect"
> ##parameters=sessionText
> ##
> session = context.REQUEST.SESSION
> sessionObjName = 'redirectTest'
> session.set(sessionObjName, sessionText)
> return
>
context.REQUEST.RESPONSE.redirect(context["view_session_obj.pt"].absolute_url())
>
> ## Page Template "view_session_obj.pt"
> ##
> <html>
> <head>
> <title tal:content="template/title">The title</title>
> </head>
> <body>
> <tal:block define="global sesObj request/SESSION/redirectTest |
> nothing"></tal:block>
> <p tal:condition="not:sesObj">Problem: no session object
> (redirectTest).</p>
> <p tal:condition="sesObj" tal:content="sesObj">session obj
> contents</p>
> </body>
> </html>
>
>
> Brad
--=_alternative 0058719686256D09_=
Content-Type: text/html; charset="us-ascii"
<br><font size=2 face="sans-serif">Thanks, Chris, for the quick reply. I tried both of your suggestions: the random query string and the setHeader statements in the ZPT. They both improved the situation in that requests after the initial one are now returned properly. However, the very first request still returns the </font><font size=2 face="Courier New">"Problem: no session object (redirectTest)" </font><font size=2 face="sans-serif">message. By the way, instead of a response.redirect, if I return the page template directly in the script with a statement like "return container['view_session_obj.pt']()", it works perfectly. Unfortunately, I need the redirect because of the way my actual page template works.</font>
<br>
<br><font size=2 face="sans-serif">Brad</font>
<br>
<br>
<br>
<br>
<table width=100%>
<tr valign=top>
<td>
<td><font size=1 face="sans-serif"><b>Chris McDonough <chrism@zope.com></b></font>
<p><font size=1 face="sans-serif">04/15/2003 10:18 AM</font>
<br>
<br><font size=1 face="sans-serif"> To: Brad Powell/PPCO@Phillips</font>
<br><font size=1 face="sans-serif"> cc: zope@zope.org</font>
<br><font size=1 face="sans-serif"> Subject: Re: [Zope] Help with session data and redirects</font></table>
<br>
<br>
<br><font size=2 face="Courier New">Under Mozilla 1.3 on Linux, when running your test (e.g. when visiting<br>
/createSessionAndRedirect?sessionText=456), I immediately get:<br>
<br>
## Page Template "view_session_obj.pt" ##<br>
<br>
456<br>
<br>
Like you, I suspect this may be a browser issue. <br>
<br>
To verify, cause the createSessionAndRedirect to generate a "random"<br>
query string like this:<br>
<br>
session = context.REQUEST.SESSION<br>
sessionObjName = 'redirectTest'<br>
session.set(sessionObjName, sessionText)<br>
return<br>
context.REQUEST.RESPONSE.redirect(context["view_session_obj.pt"].absolute_url() + '?abc=%s' % context.ZopeTime().timeTime())<br>
<br>
This should prevent browsers from returning a cached page. A more<br>
permanent solution would be to set a Pragma: No-Cache or Cache-Control:<br>
No-Cache HTTP header within "view_session_obj.pt".<br>
<br>
- C<br>
<br>
<br>
On Tue, 2003-04-15 at 10:58, Brad Powell wrote:<br>
> I have a problem where session data does not appear to be updated when the <br>
> setting of the session data is followed by a response.redirect in a Python <br>
> script. A browser refresh is required to get the correct data displayed. <br>
> This happens on both Zope v2.5.1 and v2.6.1. It also happens with IE and <br>
> Mozilla browsers; but, interestingly, it does not occur with the Konqueror <br>
> browser. This led me to believe it was a browser issue, but no matter <br>
> what options I try in IE, I cannot get it to work. I thought it might be <br>
> an issue with the browser cache settings, but, again, no matter what I try <br>
> I get the same result.<br>
> <br>
> I've included a test script and page template that demonstrates this <br>
> problem. When I go to url "sessionCreateAndRedirect?sessionText=123", I <br>
> get the message, "Problem: no session object (redirectTest)." If I then <br>
> refresh the browser, I get "123" displayed, which is the correct response. <br>
> Subsequent calls to the url with different values for sessionText returns <br>
> the previous session value, until I do a browser refresh.<br>
> <br>
> Any assistance, guidance, wisdom, etc. on this matter would be greatly <br>
> appreciated.<br>
> <br>
> <br>
> ## Script (Python) "sessionCreateAndRedirect"<br>
> ##parameters=sessionText<br>
> ##<br>
> session = context.REQUEST.SESSION<br>
> sessionObjName = 'redirectTest'<br>
> session.set(sessionObjName, sessionText)<br>
> return <br>
> context.REQUEST.RESPONSE.redirect(context["view_session_obj.pt"].absolute_url())<br>
> <br>
> ## Page Template "view_session_obj.pt"<br>
> ##<br>
> <html><br>
> <head><br>
> <title tal:content="template/title">The title</title><br>
> </head><br>
> <body><br>
> <tal:block define="global sesObj request/SESSION/redirectTest | <br>
> nothing"></tal:block><br>
> <p tal:condition="not:sesObj">Problem: no session object <br>
> (redirectTest).</p><br>
> <p tal:condition="sesObj" tal:content="sesObj">session obj <br>
> contents</p><br>
> </body><br>
> </html><br>
> <br>
> <br>
> Brad<br>
<br>
<br>
</font>
<br>
<br>
--=_alternative 0058719686256D09_=--
------=_NextPartTM-000-b09ecce5-c437-476b-9d74-66dfd231bba6--