How can I debug code for APIService

Question

I'm a newbie in creating an sign in using API in swift. I followed a video tutorial from treehouse but I used different version of Xcode and swift. I don't know what will I put in these code. Hope you could help me Or can you give me any references that I could use in creating a sign in page that will input passcode in textfield and submit to validate if the code is existing and will post data. Thank you so much.

When I click Fix these line of code appeared

final class EventAPIClient: APIService {
func JSONTaskWithRequest(request: URLRequest, completion: (JSON?, HTTPURLResponse?, NSError?) -> Void) -> JSONTask {
    <#code#>
}

init(config: URLSessionConfiguration) {
    <#code#>
}


let  configuration: URLSessionConfiguration
lazy var session: URLSession = {
return URLSession(configuration: self.configuration)
}()

private let token: String

init(config: URLSessionConfiguration, APIKey: String) {
    self.configuration = config
    self.token = APIKey
}

convenience init(APIKey: String) {

    self.init(config: URLSessionConfiguration.default, APIKey: APIKey)
}
}

Answer 1

In order to begin to resolve this issue, you need to look at what protocols are.

Focusing on information relevant to this situation, they essentially define the signature of a function (among other things). The name of the protocol and the function signature leave clues as to what a given function's implementation should be. This is easily illustrated by a simple example:

protocol MathematicalOperations {
    func add(_ int: Int, to int: Int) -> Int
}

class Calculator: MathematicalOperations {
    func add(_ intA: Int, and intB: Int) -> Int {
        return intA + intB
    }
}

// Usage
let calculator = Calculator()
let sum = calculator.add(15, and: 10)
print(sum) // 25

tying it back into your situation. The protocol APIService has defined the functions like so:

protocol APIService {
    func JSONTaskWithRequest(request: URLRequest, completion: (JSON?, HTTPURLResponse?, NSError?) -> Void) -> JSONTask
    init(config: URLSessionConfiguration)
}

Your EventAPIClient class tells the compiler it means to conform to the APIService protocol:

final class EventAPIClient: APIService {

In order to conform to the protocol, EventAPIClient needs to provide an implementation for all the definitions in APIService.

As for solving the issue, there are some missing pieces of information regarding the definition of JSONTask etc. However, here is an example implementation that should, if nothing else, give you a starting point:

func JSONTaskWithRequest(request: URLRequest, completion: @escaping (JSON?, HTTPURLResponse?, NSError?) -> Void) -> JSONTask {
    let task = session.dataTask(with: request) { data, response, error in
        if let error = error {
            completion(nil, response, error as NSError?)
        } else if HTTPResponse.statusCode == 200 { // OK response code
            do {
                let json = try JSONSerialization.jsonObject(with: data!, options: []) as? JSON
                completion(json, response, nil)
            } catch let error as NSError {
                completion(nil, response, error)
            }
        } else {
            completion(nil, response, nil) // could create an error saying you were unable to parse JSON here
        }
    }
    return task as? JSONTask
}

init(config: URLSessionConfiguration) {
    self.configuration = config
    self.token = "APIKey" // put your default api key here, maybe from a constants file?
}

I hope you find this helpful :)