What are the limitations of RealmAny?

[ammerzon]

@edualonso added support for RealmAny a few weeks ago 🥳

I am now trying to figure out what the limitations of this datatype are. Assume I have the following schema with the body as type object:

{
  "additionalProperties": false,
  "bsonType": "object",
  "properties": {
    "_id": {
      "bsonType": "objectId"
    },
    "body": {
      "bsonType": "object"
    },
    "created_at": {
      "bsonType": "date"
    }
  },
  "required": [
    "_id",
    "created_at"
  ],
  "title": "Item"
}

I would map this to the following class:

class CatalogItem : RealmObject {
    @PrimaryKey
    var _id: ObjectId = ObjectId()
    var body: RealmAny? = null
    var created_at: RealmInstant = RealmInstant.MIN
    var version: Double = 0.0
}

Is it possible to sync this RealmObject with a body that looks like this?

[edualonso]

Hi @ammerzon. Yes, it is possible to have such a body object in your current schema modelled using RealmAny. Something along these lines would work:

class CatalogItem : RealmObject {
    @PrimaryKey
    var _id: ObjectId = ObjectId()
    var body: RealmAny? = null
    var created_at: RealmInstant = RealmInstant.MIN
    var version: Double = 0.0
}

class Header : RealmObject {
    @PrimaryKey
    var _id: ObjectId = ObjectId()
}
class Body : RealmObject {
    @PrimaryKey
    var _id: ObjectId = ObjectId()
    var header: Header? = null
    var selections: RealmList<Selection> = realmListOf()
}

class Selection : RealmObject {
    @PrimaryKey
    var _id: ObjectId = ObjectId()
    var provider_description: String? = null
    var is_correct: Boolean? = null
}

// ...

val selections = listOf("A" to true, "B" to false, "C" to false).map { (description, correct) ->
    Selection().apply {
        this.provider_description = description
        this.is_correct = correct
    }
}

val body = Body().apply {
    this.header = ...
    this.selections.addAll(selections)
}
val catalogItem: CatalogItem = ...
catalogItem.body = body

// copy catalogItem to Realm and wait for sync

val item = syncedRealm.query<CatalogItem>().first.find()
val bodyObj = item.body?.asRealmObject(Body::class)

Enjoy working with RealmAny 😄

[ammerzon]

Thank you for your help 😁
Is it possible that the RealmAny Body object also has a RealmAny object? For instance a field called meta.

class CatalogItem : RealmObject {
    @PrimaryKey
    var _id: ObjectId = ObjectId()
    var body: RealmAny? = null
    var created_at: RealmInstant = RealmInstant.MIN
    var version: Double = 0.0
}

class Body : RealmObject {
    @PrimaryKey
    var _id: ObjectId = ObjectId()
    var header: Header? = null
    var selections: RealmList<Selection> = realmListOf()
    var meta: RealmAny? = null
}