A custom codable implementation, especially the test of if the value is double or string or anything and code / decode things

Custom Codable .swift

//
//  ExtractedData.swift
//  AGKitDemo-Template
//
//  Created by Anthony on 20/03/2018.
//  Copyright © 2018 AboutGoods. All rights reserved.
//

import Foundation

protocol ExtractedDataProtocol {
    func getBestValue() -> Any
}

struct ExtractedData {
    var value:Any?
    var accuracy:Double?
    
    enum CodingKeys: String, CodingKey {
        case value = "value"
        case accuracy
    }
    
}

extension ExtractedData: Encodable {
    func encode(to encoder: Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)
        
        if let doubleValue = self.value as? Double {
          
            try container.encode(doubleValue, forKey: .value)

        } else if let stringValue = self.value as? String {
          
            try container.encode(stringValue, forKey: .value)

        } else {
          
            let context = DecodingError.Context(codingPath: [CodingKeys.value], debugDescription: "Unrecognized type for value")
            throw DecodingError.valueNotFound(ExtractedData.self, context)
        }
        
        try container.encode(self.accuracy, forKey: .accuracy)
    }
}

extension ExtractedData: Decodable {
    init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        
        if let decodedValue = try? values.decode(Double.self, forKey: .value) {
            self.value = decodedValue
        
        } else if let decodedValue = try? values.decode(String.self, forKey: .value){
            self.value = decodedValue
        
        } else {
        
            let context = DecodingError.Context(codingPath: [CodingKeys.value], debugDescription: "No concording type found for value")
            throw DecodingError.valueNotFound(ExtractedData.self, context)
        }
        
        self.accuracy = try values.decode(Double.self, forKey: .accuracy)
    }
}