Parent child relationships in Loopback

Question

I have two loopback models, say Product and Service. They are related to a parent model Asset. The Asset has an AssetType which says if the current object is a Product or a Service. How do I model the entity relationships for this case?

Answer 1

Use polymorphic relations https://loopback.io/doc/en/lb3/Polymorphic-relations.html

"parent": {
    "type": "belongsTo",
    "polymorphic": {
        "foreignKey": "parentId",
        "discriminator": "parentType"
    }
}