Swift JSON Date Decoder for unix millis, secs, ISO8701 with and without fractional seconds

JSONDecoder+Date.swift

extension JSONDecoder {
    enum DateDecodeError: String, Error {
        case invalidDate
    }
    
    static var bestDateAttemptDecoder: JSONDecoder {
        let decoder = JSONDecoder()
        decoder.dateDecodingStrategy = .custom({ (decoder) -> Date in
            let container = try decoder.singleValueContainer()
            if let dateSecs = try? container.decode(Double.self) {
                return Date(timeIntervalSince1970: dateSecs)
            }
            
            if let dateSecs = try? container.decode(UInt.self) {
                return Date(timeIntervalSince1970: TimeInterval(dateSecs))
            }
            
            let dateStr = try container.decode(String.self)
            let isoFormatter = ISO8601DateFormatter()
            isoFormatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
            if let date = isoFormatter.date(from: dateStr) {
                return date
            }
            
            isoFormatter.formatOptions = [.withInternetDateTime ]
            if let date = isoFormatter.date(from: dateStr) {
                return date
            }
            
            log.warning("Cannot decode date");
            throw DateDecodeError.invalidDate
        })
        
        return decoder
    }
}