Alamofire ObjectMapper - Extract common fields from all models and map them - ios

Question

There are few fields common in all models returned by api. But they don't come as a separate object. They are there among other fields.
Example of two models :
Event :
[
{
"event":{
"id":3,
"company_id":18,
"archived":false,
"created_by":229,
"updated_by":229,
"owner_id":229,
"subject":"",
"start_date":null,
"end_date":null,
"name":null,
"name_class_name":"",
"related_to":null,
"related_to_class_name":"",
"status":"",
"created_at":"2018-05-07T01:59:38.921-04:00",
"updated_at":"2018-05-07T01:59:38.921-04:00",
"custom_nf":false
}
}
]
Opportunity :
[
{
"opportunity":{
"id":4,
"company_id":18,
"archived":false,
"created_by":229,
"updated_by":229,
"owner_id":229,
"account_id":null,
"name":"",
"lead_source":"",
"amount":null,
"close_date":null,
"probability":null,
"stage":"",
"created_at":"2018-05-07T01:49:55.441-04:00",
"updated_at":"2018-05-07T01:49:55.441-04:00"
}
}
]
As shown, initial fields are common in both (all) models - id, company_id, archived, created_by and so on.
There are tons of projects I have worked with ObjectMapper but didn't encounter this before. I am fully aware of handling nested models, but this is a different case.
Though I can easily handle this by repeating all common fields in all models. But this doesn't sound good.
What I am looking is a way I can create a separate model class with all common fields. But the question is - how would I map that with api response using ObjectMapper ?
Just as an example, this is how I have created Opportunity model :
import UIKit
import ObjectMapper
class Opportunity: NSObject, Mappable {
var id: Int?
var companyId: Int?
var archived: Int?
var createdBy: Int?
var updatedBy: Int?
var ownerId: Int?
var accountId: Int?
var name: String?
var leadSource: String?
var amount: String?
var closeDate: String?
var probability: String?
var stage: String?
var createdAt: String?
var updatedAt: String?
required init?(map: Map) {
}
func mapping(map: Map) {
self.id <- map["id"]
self.companyId <- map["company_id"]
self.archived <- map["archived"]
self.createdBy <- map["created_by"]
self.updatedBy <- map["updated_by"]
self.ownerId <- map["owner_id"]
self.accountId <- map["account_id"]
self.name <- map["name"]
self.leadSource <- map["lead_source"]
self.amount <- map["amount"]
self.closeDate <- map["close_date"]
self.probability <- map["probability"]
self.stage <- map["stage"]
self.createdAt <- map["created_at"]
self.updatedAt <- map["updated_at"]
}
}

Answer 1

You can create base entity and put there common fields.
Example:
import UIKit
import ObjectMapper
class BaseEntity: NSObject, Mappable {
var id: Int?
var companyId: Int?
var archived: Int?
var createdBy: Int?
var updatedBy: Int?
var ownerId: Int?
var name: String?
var createdAt: String?
var updatedAt: String?
required init?(map: Map) {
}
func mapping(map: Map) {
self.id <- map["id"]
self.companyId <- map["company_id"]
self.archived <- map["archived"]
self.createdBy <- map["created_by"]
self.updatedBy <- map["updated_by"]
self.ownerId <- map["owner_id"]
self.name <- map["name"]
self.createdAt <- map["created_at"]
self.updatedAt <- map["updated_at"]
}
}
class Opportunity: BaseEntity {
var accountId: Int?
var leadSource: String?
var amount: String?
var closeDate: String?
var probability: String?
var stage: String?
required init?(map: Map) {
super.init(map: map)
}
override func mapping(map: Map) {
super.mapping(map: map)
self.accountId <- map["account_id"]
self.leadSource <- map["lead_source"]
self.amount <- map["amount"]
self.closeDate <- map["close_date"]
self.probability <- map["probability"]
self.stage <- map["stage"]
}
}
Note: BaseEntity isn't good name, I think you can give better name.