modeling-users

[Modeling-users] Another question about sessions and EditingContexts (sorry)

[Ernesto R. <er...@si...>]

Dear all,

as stated in the documentation, section 6. Integration in an =
application, using an application server, actually it is recomended to =
use a fresh EditingContext for each session. But it states also, that =
changes made permanent with saveChanges will not be visible to other =
EditingContexts. Is the also the case for Zope =
ZEditingContextSessioning? Could anybody tell me in which environment =
she/he uses modeling, and how he treats the EditingContexts? (I'm =
looking for application server like uses.)

Best regards, Erny

Re: [Modeling-users] Another question about sessions and EditingContexts (sorry)

[Sebastien B. <sbi...@us...>]

"Ernesto Revilla" <er...@si...> wrote:
> Dear all,
>=20
> as stated in the documentation, section 6. Integration in an application,
> using an application server, actually it is recomended to use a fresh
> EditingContext for each session. But it states also, that changes made
> permanent with saveChanges will not be visible to other EditingContexts. =
Is
> the also the case for Zope ZEditingContextSessioning? Could anybody tell =
me
> in which environment she/he uses modeling, and how he treats the
> EditingContexts? (I'm looking for application server like uses.)

  This is the case in every multi-ECs environment, including Zope and
  ZECSessioning.

I currently have the intention of solving that longstanding issue of
synchronizing ECs --and this is a prerequisite for optimistic
locking. Would you have some time testing patches on that topic?

-- S=E9bastien.

Re: [Modeling-users] Another question about sessions and EditingContexts (sorry)

[Ernesto R. <er...@si...>]

Dear S=E9bastien,

Yes, actually I have time to do some testing in a test environment (no =
production) with sqlite and Postgresql. (And I'm sorry I couldn't help =
you with python metaclasses in the past.) I'm also very interested in =
optimistic locking.=20

With best regards,=20
Erny



----- Original Message -----=20
From: "Sebastien Bigaret" <sbi...@us...>
To: "Ernesto Revilla" <er...@si...>
Cc: "modeling-users" <mod...@li...>
Sent: Sunday, February 29, 2004 2:37 PM
Subject: Re: [Modeling-users] Another question about sessions and =
EditingContexts (sorry)



"Ernesto Revilla" <er...@si...> wrote:
> Dear all,
>=20
> as stated in the documentation, section 6. Integration in an =
application,
> using an application server, actually it is recomended to use a fresh
> EditingContext for each session. But it states also, that changes made
> permanent with saveChanges will not be visible to other =
EditingContexts. Is
> the also the case for Zope ZEditingContextSessioning? Could anybody =
tell me
> in which environment she/he uses modeling, and how he treats the
> EditingContexts? (I'm looking for application server like uses.)

  This is the case in every multi-ECs environment, including Zope and
  ZECSessioning.

I currently have the intention of solving that longstanding issue of
synchronizing ECs --and this is a prerequisite for optimistic
locking. Would you have some time testing patches on that topic?

-- S=E9bastien.

Re: [Modeling-users] Another question about sessions and EditingContexts (sorry)

[Sebastien B. <sbi...@us...>]

        Hi,

Ernesto Revilla <er...@si...> wrote:
> Dear S=E9bastien,
>=20
> Yes, actually I have time to do some testing in a test environment (no pr=
oduction) with sqlite and Postgresql. (And I'm sorry I couldn't help you wi=
th python metaclasses in the past.) I'm also very interested in optimistic =
locking.=20

Ok, thanks, such a feature needs to be double-checked, and more :)

  I began working on it yesterday evening, and hopefully we'll have a
first draft in the coming days.  The first conclusion to which I've come
is that optimistic locking is much easier to implement than the
synchronizing of ECs!  The second one is that the first implementation
will be a proof of concept, and won't work for child ECs. I'll let you
know when the first patch is available.

-- S=E9bastien.

[Modeling-users] ECs synchronization and optimistic locking [was: Re: Another question about sessions and EditingContexts]

[Sebastien B. <sbi...@us...>]

        Hi all,

  I've just uploaded a patch (#911567) for ECs synchronization upon
  saveChanges(), and for optimistic locking.

https://sf.net/tracker/index.php?func=3Ddetail&aid=3D911567&group_id=3D5893=
5&atid=3D489337


This is alpha software:

  * For now, ECs synchronization works for updated objects, not deleted
    ones, and it does not work for nested ECs.

  * Optimistic locking is implemented and works well, but it's not been
    heavily tested.

The patch is shipped with a new test, test_EC_optimistic_locking.py,
which hopefully demonstrates what can be expected from these new
features.

  Bug/error reports will be preferably directed to the corresponding
sf's ticket #911567, and discussions, questions, etc. about the new
feature can take place here on the mailing-list.  Thanks in advance to
those who will have some time to test the patch!

-- S=E9bastien.