[ZODB-Dev] ZEO and commits

[Christian Robottom Reis]

On Mon, Oct 27, 2003 at 12:33:38PM +0100, Antonio Beamud Montero wrote:
> I need a sync to update my local copy of the object, because making a
> commit not produce any Conflict situation... My experiencie is the next
>   process A <----------------- ZEO -----------------> process B
> ------------                                          ------------
>                                                    create Object X
>     ...                                            make changes in X
>     sync()                                              ....

This sync() will do nothing unless process B has commited first. Do you
have a commit() missing after create Object X there?

>    my X copy						.....
>     commit()
>     .....             nothing conflicts                 .....
>                                                      commit X changes
>                       nothing conflicts
>   
> Is this normal? When B tries to make commit X changes wouldn't raise a
> conflict? I'm a bit confused... Seems like the commit is only propagated

I can't see how B's final commit doesn't conflict with A's final
conflict. It raises a ConflictError, most certainly, unless you initiate
your transaction *after* A has committed.

You may be doing something slightly different than what you say you're
doing <wink>.

> in the local cache copy of the object... I need to make several sync
> call's in the B process to produce the conflict...?

No, you don't -- the ZODB will raise conflicts for you.

Ah, for an example _p_resolveConflict, see the BTrees Length class --
it's very simple, and easy to figure out.

Take care,
--
Christian Robottom Reis | http://async.com.br/~kiko/ | [+55 16] 261 2331