[Zope] Re: Florent Guillaume's database Conflict Error on session objects patch not working ?

[yacine chaouche]

I forward your message to the list.

I installed faster :
1) It has no INSTALL file
2) I created a better session manager object under the id newSession,
and hit the test button. I Got this error :



Traceback (most recent call last):
  File "/opt/aef/Zope-2.9.0/lib/python/ZPublisher/Publish.py", line
113, in publish
    request, bind=1)
  File "/opt/aef/Zope-2.9.0//lib/python/ZPublisher/mapply.py", line
88, in mapply
    if debug is not None: return debug(object,args,context)
  File "/opt/aef/Zope-2.9.0/lib/python/ZPublisher/Publish.py", line
40, in call_object
    result=apply(object,args) # Type s<cr> to step into published object.
  File "/opt/aef/Zope-2.9.0//lib/python/Shared/DC/Scripts/Bindings.py",
line 311, in __call__
    return self._bindAndExec(args, kw, None)
  File "/opt/aef/Zope-2.9.0//lib/python/Shared/DC/Scripts/Bindings.py",
line 329, in _bindAndExec
    def _bindAndExec(self, args, kw, caller_namespace):
  File "/opt/aef/Zope-2.9.0//lib/python/Shared/DC/Scripts/Bindings.py",
line 348, in _bindAndExec
    return self._exec(bound_data, args, kw)
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/PageTemplateFile.py",
line 110, in _exec
    return self.pt_render(extra_context=bound_names)
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/PageTemplate.py",
line 104, in pt_render
    tal=not source, strictinsert=0)()
  File "/opt/aef/Zope-2.9.0//lib/python/TAL/TALInterpreter.py", line
234, in __call__
    def __call__(self):
  File "/opt/aef/Zope-2.9.0//lib/python/TAL/TALInterpreter.py", line
238, in __call__
    self.interpret(self.program)
  File "/opt/aef/Zope-2.9.0//lib/python/TAL/TALInterpreter.py", line
281, in interpret
    handlers[opcode](self, args)
  File "/opt/aef/Zope-2.9.0//lib/python/TAL/TALInterpreter.py", line
507, in do_setLocal_tal
    self.engine.setLocal(name, self.engine.evaluateValue(expr))
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/TALES.py",
line 221, in evaluate
    return expression(self)
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/Expressions.py",
line 182, in __call__
    def __call__(self, econtext):
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/Expressions.py",
line 185, in __call__
    return self._eval(econtext)
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/Expressions.py",
line 180, in _eval
    return render(ob, econtext.vars)
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/Expressions.py",
line 88, in render
    raise
  File "/opt/aef/Zope-2.9.0//lib/python/Products/PageTemplates/Expressions.py",
line 85, in render
    ob = ob()
  File "/opt/aef/Zope-2.9.0/lib/python/Products/faster/sessiondata.py",
line 255, in addItemsToSession
    before = len(session)
AttributeError: __len__

Do you use a bug reporting system or something for your product ?

Thank you,

Y.Chaouche


2007/2/2, Tres Seaver <tseaver at palladion.com>:
>
>
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>
> yacine chaouche wrote:
> > Hi all,
> >
> > As discussed  here :
> > http://mail.zope.org/pipermail/zope/2007-January/170151.html
> > and continued here :
> > http://mail.zope.org/pipermail/zope/2007-January/170156.html
> >
> > I am experiencing issues regarding a database ConflictError on session objects.
> >
> > I use zope 2.9.0 python 2.4.2, and the code of the MultiDB support has
> > been patched (as suggested by Florent Guillaume)
> > http://mail.zope.org/pipermail/zodb-dev/2006-January/009737.html
> >
> > My main concern is to debug my application where, on every couple of
> > requests coming from two different browsers at the same time (before
> > the first request is , one of them wins and the other always fails and
> > raises a conflict error. It is not a ReadConflictError, nor a
> > WriteConflictError. It is a "ConflictError: database conflict error".
> > I am aware that conflicts occure up to 20% of the time, but in my case
> > it is almost 100% in this specific situation !
> >
> > If I do not use the session object in my code, I have no errors at all
> > and everything just goes fine.
> >
> > Any idea on how to debug this ? Florent, maybe ?  someone help me ! I
> > am stuck on this for 2 weeks now.
> >
> > NOTE : I do not use Zeo, nor frames.
>
> You might try 'faster', an alternative ZODB-based sessioning
> implementation:  one of its goals is to reduce the chance of collisions
> compared to the stock implementation:
>
>   http://agendaless.com/Members/tseaver/software/faster/
>
>
> Tres.
> - --
> ===================================================================
> Tres Seaver          +1 540-429-0999          tseaver at palladion.com
> Palladion Software   "Excellence by Design"    http://palladion.com
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