Encoding/decoding struct as JSON embedded in a binary plist

misc.swift

import ArgumentParser
import Foundation

struct MyStruct: Codable {
    var id: Int = 0
    var name: String = ""
    var port: Int?
}

let myStructKey = "myStructs"

@main
struct NSKeyedTester: ParsableCommand {
    static var configuration = CommandConfiguration(
        abstract: "NSKeyedArchiver tests",
        subcommands: [Read.self, Write.self],
        defaultSubcommand: Write.self)

    struct Options: ParsableArguments {
        @Argument var filename: String = "./hello.plist"
    }

    struct Read: ParsableCommand {
        @OptionGroup var options: Options

        mutating func run() throws {
            let localURL = URL(fileURLWithPath: options.filename)
            let data = try Data(contentsOf: localURL)
            let unarchiver = try NSKeyedUnarchiver(forReadingFrom: data)
            let json = unarchiver.decodeDecodable(String.self, forKey: myStructKey)!
            let decoder = JSONDecoder()
            let decoded = try decoder.decode(Array<MyStruct>.self, from: json.data(using: .utf8)!)
            print(decoded)
        }
    }

    struct Write: ParsableCommand {
        @OptionGroup var options: Options

        mutating func run() throws {
            let localURL = URL(fileURLWithPath: options.filename)
            let encoder = JSONEncoder()
            let data = try encoder.encode([
                MyStruct(id: 1, name: "Test"),
                MyStruct(id: 100, name: "Hello"),
                MyStruct(id: 100, name: "With port", port: 100),
            ])
            let json = String(data: data, encoding: .utf8)!
            let archiver = NSKeyedArchiver(requiringSecureCoding: true)
            archiver.outputFormat = .binary
            try archiver.encodeEncodable(json, forKey: myStructKey)
            archiver.finishEncoding()
            try archiver.encodedData.write(to: localURL)
        }
    }
}