DateFormatTransform.swift

//
//  DateFormatTransform.swift
//
//  Created by Rodolfo Antonici on 29/11/16.
//  No copyright, just use it as it's.
//  ObjectMapper version 2.2
//
//  A simple class using the TransformType protocol of ObjectMapper to convert Date String into a NSDate object

import Foundation
import ObjectMapper
public class DateFormatTransform: TransformType {
    public typealias Object = NSDate
    public typealias JSON = String
    
    var dateFormat = NSDateFormatter(dateFormat: "yyyy-MM-dd'T'HH:mm:ss")
    
    convenience init(dateFormat: String) {
        self.init()
        self.dateFormat = NSDateFormatter(dateFormat: dateFormat)
    }
    
    public func transformFromJSON(value: AnyObject?) -> Object? {
        if let dateString = value as? String {
            return self.dateFormat.dateFromString(dateString)
        }
        return nil
    }
    public func transformToJSON(value: NSDate?) -> JSON? {
        if let date = value {
            return self.dateFormat.stringFromDate(date)
        }
        return nil
    }
}


// Sample Usage:


//class SomeObject: Mappable {
//
//    var name: String?
//    var categorizationDate: NSDate?
//    var startDate: NSDate?
//    var endDate: NSDate?
//
//    required convenience init?(_ map: Map) {
//        self.init()
//    }
//    
//      Using the same object to multiple Date fields (performance benefits)
//    override func mapping(map: Map) {
//        super.mapping(map)
//        
//        let dateFormatTransformer = DateFormatTransform(dateFormat: "yyyy-MM-dd'T'HH:mm:ss")
//        
//        name <- map["name"]
//        categorizationDate <-  (map["categorization"], dateFormatTransformer)
//        startDate <- (map["start"], dateFormatTransformer)
//        endDate <- (map["end"], dateFormatTransformer)
//    }
//
//              A direct approach to a single format to each field or when there's a single field
//    override func mapping(map: Map) {
//        super.mapping(map)
//
//        name <- map["name"]
//        categorizationDate <-  (map["categorization"], DateFormatTransform(dateFormat: "yyyy-MM-dd'T'HH:mm:ss"))
//        startDate <- (map["start"], DateFormatTransform(dateFormat: "yyyy-MM-dd"))
//        endDate <- (map["end"], DateFormatTransform(dateFormat: "HH:mm:ss"))
//    }
//}