[Zope] Session manager without pickle?

[Dietmar Schwertberger]

In <URL:news:local.ZOPE> on Fri 26 Apr, Chris McDonough wrote:

> > Unfortunately the session manager tries to pickle the connection object,
> > which of course doesn't work here.
> > Is it possible to avoid this?

> It'll probably be a requirement in this case to either:

> - create a "transient object container" that doesn't use the ZODB (which
> is ultimately doing the pickling that is causing you problems) to store
> data.

> ... or ..

> - to "hack around" the problem by registering a connection with a global
> connection registry for each session and storing a (string) reference to
> it in the session (instead of storing the connection object itself).

> > Anyway, as session data should be stored in RAM, I don't see the point of
> > pickling...

> That would make life simple, but it's not always true.  People want
> persistent sessions as well as the ability to share session data across
> ZEO clients, and the current transient data container implementation
> lets that happen by using the ZODB to store session data.  The fact that
> the OOTB sessioning implementation in Zope uses ZODB to store session
> data is what is causing you problems here.

I'm using a more or less standard installation.
The session manager is configured to use /temp_folder/session_data as
Transient object container.

The help text for the Temporary Folder tells me:

 Temporary Folders are Folders which store their contents "in-memory", in
 much the same way as a RAM disk. The contents of a Temporary Folder are
 lost upon shutdown.
 [snip]
 Since Temporary Folders use RAM to store data, it is advised to add items
 to a Temporary Folder sparingly. The capacity of a Temporary Folder is
 limited by available RAM.

So I really got the impression that my sessions would be stored in RAM...



> BTW, are you aware that the relational database support in Zope does its
> own "connection pooling" and that schemes like this that are commonly
> used in Java for this kind of thing aren't really necessary?

Yes, but would that help me if I want transactions over multiple page
fetches? Don't think so.
I'm not sure whether I'll really need this. The first applications will
be quite simple and read-only (I still will use the Python database
connection for user authentication, but for this purpose the connection
may be closed after the login).
Most write accesses will be from Python apps outside Zope.


Regards,

Dietmar