struct Photo: Codable {

    let hasShadow: Bool
    let image: UIImage?

    enum CodingKeys: String, CodingKey {
        case `self`, hasShadow, image
    }

    init(hasShadow: Bool, image: UIImage?) {
        self.hasShadow = hasShadow
        self.image = image
    }

    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        hasShadow = try container.decode(Bool.self, forKey: .hasShadow)

        // This fails
        image = try container.decode(UIImage?.self, forKey: .image)
    }

    func encode(to encoder: Encoder) throws {
        var container = encoder.container(keyedBy: CodingKeys.self)
        try container.encode(hasShadow, forKey: .hasShadow)

        // This also fails
        try container.encode(image, forKey: .image)
    }
}