A Swift 4 extension for JSONEncoder and JSONDecoder to enable serialization to/deserialization from JSON Objects (e.g. [String: Any])

JSONCodable+JSONObjects.swift

import Foundation

extension JSONEncoder {
    func encodeJSONObject<T: Encodable>(_ value: T, options opt: JSONSerialization.ReadingOptions = []) throws -> Any {
        let data = try encode(value)
        return try JSONSerialization.jsonObject(with: data, options: opt)
    }
}

extension JSONDecoder {
    func decode<T: Decodable>(_ type: T.Type, withJSONObject object: Any, options opt: JSONSerialization.WritingOptions = []) throws -> T {
        let data = try JSONSerialization.data(withJSONObject: object, options: opt)
        return try decode(T.self, from: data)
    }
}