Re: [Sqlalchemy-tickets] [sqlalchemy] #1128: before_flush() sucks

[sqlalchemy <mi...@zz...>]

#1128: before_flush() sucks
--------------------------------+-------------------------------------------
    Reporter:  zzzeek           |       Owner:  zzzeek              
        Type:  defect           |      Status:  new                 
    Priority:  high             |   Milestone:  0.5.0               
   Component:  orm              |    Severity:  minor - half an hour
  Resolution:                   |    Keywords:                      
Status_field:  awaiting triage  |  
--------------------------------+-------------------------------------------
Old description:

> 1. needs a simple "reentrant" blocker so that autoflush on lazyload is
> blocked throughout the execution of `session.flush()`
> 2. the reentrant blocker should raise an error for an explicit userland
> call to `session.flush()`.
> 3. the "new", "dirty" and "deleted" lists need to be (re-)calculated
> '''after''' the `before_flush()` method executes, geez...  i.e.
>
> {{{
> dirty = self._dirty_states
>
> # ... (check for nothing dirty) ...
>
> # now we're flushing
> flush_context = UOWTransaction(self)
>
> if self.extension is not None:
>     self.extension.before_flush(self, flush_context, objects)
>
>     # recalculate !
>     dirty = self._dirty_states
>
> # *now* get these
> deleted = set(self._deleted)
> new = set(self._new)
>
> dirty = set(dirty).difference(deleted)
> }}}

New description:

 1. needs a simple "reentrant" blocker so that autoflush on lazyload is
 blocked throughout the execution of `session.flush()`

 2. the reentrant blocker should raise an error for an explicit userland
 call to `session.flush()`.

 3. the "new", "dirty" and "deleted" lists need to be (re-)calculated
 '''after''' the `before_flush()` method executes, geez...  i.e.

 {{{
 dirty = self._dirty_states

 # ... (check for nothing dirty) ...

 # now we're flushing
 flush_context = UOWTransaction(self)

 if self.extension is not None:
     self.extension.before_flush(self, flush_context, objects)

     # recalculate !
     dirty = self._dirty_states

 # *now* get these
 deleted = set(self._deleted)
 new = set(self._new)

 dirty = set(dirty).difference(deleted)
 }}}

-- 
Ticket URL: <http://www.sqlalchemy.org/trac/ticket/1128#comment:1>
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