Re: [Pharo-users] Group and member with Voyage

Sept. 10, 2013

      no, it should not be implemented, no need to make him answer false (in fact, I never tried, but I'm pretty sure that is you reimplement isVoyageRoot to answer false in the subclasses most probably you will get a class that is transient :( ). 

reason is that voyage looks the root class of a hierarchy by noticing where is #isVoyageRoot = true implemented. 

(again, each time I look in this "design decisions" I feel a bit ashamed... but well, they looked good at the moment :) ) 

Esteban

On Sep 10, 2013, at 5:06 PM, Esteban A. Maringolo <emaringolo@gmail.com> wrote:
...
Esteban,
I didn't know about the #isVoyageRoot difference based on where was the method defined.
I mean... if I define  
Member class>>#isVoyageRoot 
    ^true
why sould SingleMember answer false?
Do I have to redefine it to answer false in each of Member subclasses?
Regards!
Esteban A. Maringolo
2013/9/10 Esteban Lorenzano <estebanlm@gmail.com>
Hi,
what happens is that if you declare a "kind", you forces all elements to be of that specific class.
Solution is just not add that property:
<mongoDescription>
        ^VOMongoToManyDescription new
                attributeName: 'members';
                accessor: #members;
                "kind: Member; "                                                "<-- NO!"
                beLazy;
                yourself.
And same happens in the <mongoContainer> description in the top of your hierarchy... you must NOT declare a kind.
Also, if you want all members to go in just one collection. #isVoyageRoot has to be implemented in the top of the hierarchy and not in the subclasses
Member                                                                          "<-- #isVoyageRoot = true here!"
        SingleMember
        ComplexMember
what happens then is that voyage will create a collection and for each document it stores in it will also store the attribute '#instanceOf', which will be used to retrieve the correct object.
Esteban
what happens then is that
On Aug 31, 2013, at 12:53 AM, Esteban A. Maringolo <emaringolo@gmail.com> wrote:
...
More or less, I have this working.
In the Group class I have a description named:
descriptionMembers
<mongoDescription>
^VOMongoToManyDescription new
attributeName: 'members';
accessor: #members;
kind: Member;
beLazy;
yourself
And in the Member class I have
descriptionGroups
<mongoDescription>
^VOMongoToManyDescription new
     attributeName: 'groups';
     accessor: #groups;
     kind: Group;
     beLazy;
     yourself
But what if Member is an abstract class and the elements can be any of
SingleMember or ComplexMember?, each one is stored in a separate
collection in Mongo.
If I do specify #kind: Member in my #descriptionMembers it won't work.
Any ideas?
Regards,
Esteban A. Maringolo
2013/8/30 Esteban A. Maringolo <emaringolo@gmail.com>:
...
2013/8/30 James Foster <Smalltalk@jgfoster.net>:
...
It seems that I mistook the question for something easy enough for me to answer! Unfortunately, I don't have any knowledge of Voyage+MongoDB so can't really give the proper answer.
Thanks anyway, it is a problem you'll never find in GemStone/S ;-)