Hi Sabine,
Sadly there is no automatic solution for your problem.
I managed to resolve that by hacking the mongo description this way:
Trip class>> isVoyageRoot = true
Day class>> isVoyageRoot = false
VehicleTrip class>> isVoyageRoot = false
Now, the trick is that since the document will be something like:
Trip {
days {
Day {
VehicleTrip { ... day}
VehicleTrip { ... day}
}
}
}
(that's of course, pseudo coding heavily ;) )
Actually, since all VehicleTrips will be part of Day subdocument, you do not
need to store them.
What you really need is to have the back-reference when you reconstruct the
document
You can achieve that by declaring transient the #day attribute of VehicleTrip
and setting the day back when you read Day from the database:
VehicleTrip class>>mongoDay
<mongoDescription>
^ VOMongoTransientDescription new
attributeName: 'day';
yourself
Day class>>mongoVehicleTrips
<mongoDescription>
^VOMongoToManyDescription new
attributeName: 'vehicleTrips';
accessor: (MAPluggableAccessor
read: [ :day | day vehicleTrips ]
write: [ :day :trips |
trips do: [ :each | each day: day ].
day vehicleTrips: trips ]);
yourself
I think that will solve your embedded-cyclic problem.
yes... it is a bit hacky, but it works perfectly :)
Cheers,
Esteban
On Aug 12, 2013, at 11:33 AM, Sabine Knöfel <sabine.knoe...@gmail.com> wrote:
> Hi Esteban,
>
> thank you for the solution with the VOMongoToOneDescription.
> This works perfect for me.
>
> I have to come back to the circular references.
> I am not sure if this is a bug.
>
> I have the following model:
>
> Trip ->> Day <->> VehicleTrip
>
> One Trip has N Days.
> One Day has N VehicleTrips.
> The VehicleTrip points back to its Day.
> The Trip is voyageRoot.
>
> But I dont want Day or VehicleTrip to be voyageRoot, too.
> (In my opinion this does not make sense).
>
> If I try to save the trip, I get the endless loop.
> Attention, the Image freezes then. :-)
>
> How would you solve this? Also with the VOMongoToOneDescription solution?
> You can reproduce it with the fileout below.
>
> Regards
> Sabine
>
> This is the fileout:
>
> Object subclass: #Day
> instanceVariableNames: 'date vehicleTrips'
> classVariableNames: ''
> poolDictionaries: ''
> category: 'RKA24-Demo'!
>
> !Day methodsFor: 'accessing' stamp: 'sabineknoefel 8/12/2013 11:13'!
> date: anObject
>
> date := anObject! !
>
> !Day methodsFor: 'accessing' stamp: 'sabineknoefel 8/12/2013 11:15'!
> vehicleTrips: anObject
>
> vehicleTrips := anObject! !
>
>
> Object subclass: #VehicleTrip
> instanceVariableNames: 'day description'
> classVariableNames: ''
> poolDictionaries: ''
> category: 'RKA24-Demo'!
>
> !VehicleTrip methodsFor: 'accessing' stamp: 'sabineknoefel 8/12/2013 11:13'!
> day: anObject
>
> day := anObject! !
>
> !VehicleTrip methodsFor: 'accessing' stamp: 'sabineknoefel 8/12/2013 11:14'!
> description: anObject
>
> description := anObject! !
>
>
> Object subclass: #Trip
> instanceVariableNames: 'days description'
> classVariableNames: ''
> poolDictionaries: ''
> category: 'RKA24-Demo'!
>
> !Trip methodsFor: 'accessing' stamp: 'sabineknoefel 8/12/2013 11:14'!
> days: anObject
>
> days := anObject! !
>
> !Trip methodsFor: 'accessing' stamp: 'sabineknoefel 8/12/2013 10:12'!
> description: anObject
>
> description := anObject! !
>
> "-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- "!
>
> Trip class
> instanceVariableNames: ''!
>
> !Trip class methodsFor: 'as yet unclassified' stamp: 'sabineknoefel
> 8/12/2013 11:15'!
> demo
> |theTrip theDay theVehicleTrip|
> theTrip := Trip new description: 'Trip to Munic'.
> theDay := Day new date: Date today.
> theVehicleTrip := VehicleTrip new description: 'with car to fair'.
> theVehicleTrip day: theDay.
> theTrip days: (OrderedCollection with: theDay).
> theDay vehicleTrips: (OrderedCollection with: theVehicleTrip ).
>
> theTrip halt save ! !
>
> !Trip class methodsFor: 'as yet unclassified' stamp: 'sabineknoefel
> 8/12/2013 09:47'!
> isVoyageRoot
> ^true! !
>
>
>
>
>
> |theTrip theDay theVehicleTrip|
> theTrip := Trip new description: 'Trip to Munic'.
> theDay := Day new date: Date today.
> theVehicleTrip := VehicleTrip new description: 'with car to fair'.
> theVehicleTrip day: theDay.
> theTrip days: (OrderedCollection with: theDay).
> theDay vehicleTrips: (OrderedCollection with: theVehicleTrip ).
>
> theTrip inspect
>
>
>
> --
> View this message in context:
> http://forum.world.st/Voyage-Circular-references-tp4691940p4703303.html
> Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.
>
