defining relationships in Backbone-Relational -- not sure which direction the options are pointing?
I'm having a heckuva time understanding the documentation for Backbone-Relational; it's not 100% clear on which relation to add things like includeInJSON
. Probably best to describe my confusion by illustrating the structure I'm trying to create. I have a Venue
model that has zero or more nested Address
models (1:n relationship). The backend store is MongoDB, which can have embedded objects. I'd like to store it in this format:
{
id: 12345,
label: 'OPUS Cafe Bistro',
addresses: [
{
type: 'mailing',
address1: '#52 - 650 Duncan Ave',
city: 'Penticton, BC'
},
{
type: 'main',
address1: '#106 - 1475 Fairview Rd',
city: 'Penticton, BC'
}
]
}
(Please ignore the ugly data structures; I've adjusted it for brevity.) Now I believe I set up the relationship between Venue
and Address
thusly:
var Venue = Backbone.RelationalModel.extend({
relations: [
{
type: Backbone.HasMany,
key: 'addresses',
relatedModel: 'Address',
includeInJSON: false,
collectionType: 'Addresses',
reverseRelation: {
key: 'venue'
}
}
});
If I understand correctly, I set includeInJSON
to false in order to prevent the Venue
from being serialised into the venue
key in Address
, but under reverseRelation I leave includeInJSON
blank in order to have the full Address
(without a venue property) serialised as an array in the addresses
property of the Venue
– as per my hoped-for example. Correct?
By the same token, I'm trying to understand the same concept in relation to a join-style relationship. Consider that Venue
now has an organisationID
field:
/* venue in JSON format */
{
id: 12345,
organisationID: 336,
label: 'OPUS Cafe Bistro',
addresses: []
}
/* and now for the organisation */
{
id: 336,
label: 'OPUS Entertainment Group'
}
Using the exa开发者_开发知识库mples in the documentation, which seem to prefer the Backbone.HasMany
relationship, I think that I'd have to set up Organisation
thus:
var Organisation = Backbone.RelationalModel.extend({
relations: [
{
type: Backbone:HasMany,
key: 'venues',
relatedModel: 'Venue',
includeInJSON: Backbone.Model.prototype.idAttribute,
collectionType: 'Venues',
reverseRelation: {
key: 'organisationID',
includeInJSON: false
}
}
]
});
... which should serialise into the above example, right? (I.e., Venue
grabs Organisation
's id
and inserts it into organisationID
, and Organisation
doesn't serialise any list of Venues
)
Thanks in advance for any help – looking forward to using this handy library, after clawing my eyeballs out trying to write my own relational glue for Backbone.js :-)
(copying my answer from https://github.com/PaulUithol/Backbone-relational/issues/37 over here, so more people can hopefully find it)
I'm sure you've figured it out by now, sorry for replying so late, but just to be sure: options (like collectionType
and includeInJSON
) apply to the key
that's within the same object.
So, for your first example, you could write the relation as:
var Venue = Backbone.RelationalModel.extend({
relations: [
{
type: Backbone.HasMany,
key: 'addresses',
relatedModel: 'Address',
includeInJSON: true,
collectionType: 'Addresses',
reverseRelation: {
key: 'venue',
includeInJSON: 'id'
}
}
});
This will create a Venue that HasMany
addresses
. The addresses
key for any given Venue uses the collectionType
Addresses
, and is fully serialized because includeInJSON
is set to true
(not that the default value for includeInJSON
is also true
; so if you don't specifiy it, it will fully serialize a relation
or reverseRelation
).
The reverseRelation
simply takes the same options, only applies them with respect to the venue
key on any Address. In this case, it will only serialize the venue.id
property for the venue it's linked to.
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