Smalltalk - Re: Voyage: Circular references

Smalltalk › Pharo › Pharo Smalltalk Users

Re: Voyage: Circular references

Posted by Bernat Romagosa on Jul 19, 2013; 8:42am
URL: https://forum.world.st/Voyage-Circular-references-tp4691940p4699502.html

Hi Sabine!

If you want an object to be referenced by another, and not embedded in it, you need to give that object root entity. As a root, the object will have a collection of its own, and will be referenced by other objects by id. If the object is not root, it will be embedded inside the referring object as a property.

So, to be safe, always set #isVoyageRoot to return true at class side of all objects you don't want to have embedded. In general, "big enough" objects who are referenced by different objects should be root.

In my case, I had a centre which had users which had centres. Users also had projects, and projects also had users. Big mess, I know. Besides that, all users, centres and projects had profiles. My solution was to make centres, projects and users be roots, and let only the profiles be embedded.

I hope this helped!

Bernat.

2013/7/19 Sabine Knöfel <[hidden email]>

Hi Esteban,

yes, now the Rectangle Example works after doing the reset.

But saving my model still leads to a non responding image because
Voyage is trying to write json for all model stuf deep deep deep and
circular. Perhaps same like:
http://forum.world.st/Voyage-Circular-references-td4691940.html#a4699436

I dont know anything about Magritte (yet) and I need a hint what to
define in my model so that it stops creating json at certain points
and creates only e.g. a Symbol.

Example: My model instance of trip has a connection to an instance of
country. The country should not be written in json with all its
definitions. Voyage should only write e.g. #germany in the json and
later, when getting the instance back from the database, I want to
reassign the trip to the country.

I already implemented this stuff when working witk Mongotalk the last
months and it worked fine. But my question yesterday:
http://forum.world.st/MongoDB-open-close-in-production-singleton-or-not-td4699322.html
lead to my impression that I should use voyage.

So, how can I define the "borders"?

Sabine

On Thu, Jul 18, 2013 at 7:45 PM, EstebanLM [via Smalltalk]
<[hidden email]> wrote:

> Hi Sabine,
>
> Probably you do not missed anything.
> Probably I missed to update the voyage configuration :)
>
> can you try doing
>
> VOMongoRepository allInstancesDo: #reset.
>
> before trying again?
>
> Cheers,
> Esteban
>
> On Jul 18, 2013, at 6:31 PM, Sabine Knöfel <[hidden email]> wrote:

>
>> I found this:
>> http://smallworks.eu/web/blog/2013-06-14-voyage-the-adventure
>>
>> Chapter "Enhancing storage"
>> But if I add the 3+1 methods to Rectangle, and save it again, the json did
>> not change.
>>
>> Did I miss something?
>>
>>
>>
>>
>> --
>> View this message in context:
>> http://forum.world.st/Voyage-Circular-references-tp4691940p4699436.html
>> Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.
>>
>
>
>
>
> ________________________________
> If you reply to this email, your message will be added to the discussion
> below:
> http://forum.world.st/Voyage-Circular-references-tp4691940p4699443.html
> To unsubscribe from Voyage: Circular references, click here.
> NAML

View this message in context: Re: Voyage: Circular references

Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

--
Bernat Romagosa.