JSONRPCKit-Example.swift

import Foundation
import JSONRPCKit

struct CastError<ExpectedType>: Error {
    let actualValue: Any
    let expectedType: ExpectedType.Type
}

struct Subtract: JSONRPCKit.Request {
    typealias Response = Int
    
    let minuend: Int
    let subtrahend: Int
    
    var method: String {
        return "subtract"
    }
    
    var parameters: Any? {
        return [minuend, subtrahend]
    }
    
    func response(from resultObject: Any) throws -> Response {
        if let response = resultObject as? Response {
            return response
        } else {
            throw CastError(actualValue: resultObject, expectedType: Response.self)
        }
    }
}

let batchFactory = BatchFactory()
let batch = batchFactory.create(Subtract(minuend: 10, subtrahend: 5))
print(batch.requestObject)

let url = URL(string: "https://jsonrpckit-demo.appspot.com/")!
var request = URLRequest(url: url)
request.httpMethod = "POST"

var headers = request.allHTTPHeaderFields ?? [:]
headers["Content-Type"] = "application/json"
request.allHTTPHeaderFields = headers

request.httpBody = try? JSONSerialization.data(withJSONObject: batch.requestObject, options: [])

let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
    if let data = data {
        let json = try! JSONSerialization.jsonObject(with: data, options: [])
        print(json)
        let response = try! batch.responses(from: json)
        print(response)
    }
    if let error = error {
        print(error)
    }
}
task.resume()

while (true) {}