[Zope] accessing session data error

20 Jun 2005

      Hi all:

I think that I found a ZOPE bug. Is really very important for me know what 
can I do for avoid it. The first 9 steps are to recreate the situation and 
the other steps are to provoke the error.

Step 1: Crate a folder called "reproducingError" in Zope Interface Manage

Step 2: create a page template called "index_html" in the "reproducingError" 
folder with the following content:
"
<!-- index_html page template -->
<form name="form1" method="post" action="reproducingError/init">
  <input type="text" name="user">
  <input type="submit" name="Submit" value="Submit">
</form>
"

Step 3: create a python script called "init" in the "reproducingError" 
folder with the following content:
"
# init script
sessionData = container.REQUEST.SESSION
sessionData.set("userId", container.REQUEST.user)
return context.init2_html()
"

Step 4: create a page template called "init2_html" in the "reproducingError" 
folder with the following content:
"
<!-- init2_html page template -->
<a href="init2">passing face 2</a>
"

Step 5: create a python script called "init2" in the "reproducingError" 
folder with the following content:
"
# init2 script
request = context.REQUEST
sessionData = request.SESSION
sessionData.set('idService', 'testService')
context.first()
return context.external(context)
"

Step 6: create a page template called "first_html" in the "reproducingError" 
folder with the following content:
"
First Response
"

Step 7: create a python script called "first" in the "reproducingError" 
folder with the following content:
"
# first script
response = container.REQUEST.RESPONSE
str = container.first_html()
response.write(str)
response.flush()
"

Step 8: create an external method called "external" in the 
"reproducingError" folder with the following content, in where the function 
of the external method is "communicationResponse" and the module is any name 
that you give to the file:
"
# external method
import time
def communicationResponse(context):
    response = context.REQUEST.RESPONSE
    sessionData = context.REQUEST.SESSION
    strDetailEnd = "<script>window.location='reproducingError/end'</script>"

    for item in range(1, 40):
        time.sleep(3)
        response.write("Response iteration:" + str(item))
        response.flush()
    response.write(strDetailEnd)
    response.flush()
"

Step 9: create a python script called "end" in the "reproducingError" folder 
with the following content:
"
# end script
idService = context.REQUEST.SESSION['idService']
return "Fin - " + idService
"

Step 10: open two explorer in wich call the object "reproducingError" 
(Example: localhost:8080/reproducingError)

Step 11: enter an example text in each one.

Step 12: clink in the link of one of them, and 5 second later clink on the 
link of the other explorer. The waiting for around 5 second is necesary 
because with other time interval not allways get the error.

Stpe 13: and wait the "Response iteration"...  Please if the error don't 
appear in any of the pages, begins at Step 9 again. and try to count to 5 
witch other velocity :)

The correct result is:
"
Fin - testService
"

The error is:
"
Site Error
An error was encountered while publishing this resource. 
Error Type: KeyError
Error Value: 'idService'
"
The traceback:
"
Traceback (innermost last):
  Module ZPublisher.Publish, line 101, in publish
  Module ZPublisher.mapply, line 88, in mapply
  Module ZPublisher.Publish, line 39, in call_object
  Module Shared.DC.Scripts.Bindings, line 306, in __call__
  Module Shared.DC.Scripts.Bindings, line 343, in _bindAndExec
  Module Products.PythonScripts.PythonScript, line 323, in _exec
  Module None, line 2, in end
   - <PythonScript at /approach/reproducingError/end>
   - Line 2
  Module AccessControl.ZopeGuards, line 67, in guarded_getitem
  Module Products.Transience.TransientObject, line 176, in __getitem__
KeyError: 'idService'
"

I will appreciate if you try until the error appear, because I not always 
obtain the error. I thinks that it is bacause the time interval between the 
two request.

A curious thing is that when I obtain the error, if I wait around 15 second 
and refresh the page in wich i obtain the error, the correct result appear.. 
and no errors come.

Sorry for the extended message, but I need any help that you can give me, 
because this describe error environment imitate a funcionality that I must 
give in a system very import that i'm doing.

I'm using Zope 2.7.6 for Windows.

Thanks in advanced.
Leticia

[Zope] accessing session data error

Leticia Larrosa