What could be best way to reduce redundant code - ios

Question

I wanted to reduce repetition in this code which I got from ExDeveloper. I have a server model where I've all my networking code. Now I've just shown 3 methods here. But eventually it'll grow & there would be 70+ methods. I don't want to repeat task code which is common in all methods.
What is the best way to do it without using a 3rd party like Alamofire, etc.?
func login(userName: String, password: String, onSuccess: #escaping(JSON) -> Void, onFailure: #escaping(Error) -> Void){
let url : String = ""
let request: NSMutableURLRequest = NSMutableURLRequest(url: NSURL(string: url)! as URL)
request.httpMethod = "GET"
let session = URLSession.shared
let task = session.dataTask(with: request as URLRequest, completionHandler: {data, response, error -> Void in
if(error != nil){
onFailure(error!)
} else{
print(response as Any)
}
})
task.resume()
}
//====================
func signUp(userName: String, password: String, email: String, onSuccess: #escaping(JSON) -> Void, onFailure: #escaping(Error) -> Void){
let url : String = ""
let request: NSMutableURLRequest = NSMutableURLRequest(url: NSURL(string: url)! as URL)
request.httpMethod = "GET"
let session = URLSession.shared
let task = session.dataTask(with: request as URLRequest, completionHandler: {data, response, error -> Void in
if(error != nil){
onFailure(error!)
} else{
print(response as Any)
}
})
task.resume()
}
//====================
func forgot(email: String, onSuccess: #escaping(JSON) -> Void, onFailure: #escaping(Error) -> Void){
let url : String = ""
let request: NSMutableURLRequest = NSMutableURLRequest(url: NSURL(string: url)! as URL)
request.httpMethod = "GET"
let session = URLSession.shared
let task = session.dataTask(with: request as URLRequest, completionHandler: {data, response, error -> Void in
if(error != nil){
onFailure(error!)
} else{
print(response as Any)
}
})
task.resume()
}

Answer 1

You could split up the requests into more modular components like network layers.
Check out this guide: https://medium.com/#danielemargutti/network-layers-in-swift-7fc5628ff789

Answer 2

As you've written the above code, each function is exactly identical. So put that in a separate function that they all call. If there are parts that aren't identical (that you didn't provide), then pass those to the shared function. If there is code that changes, pass that as a function parameter.
In short: extract the parts that don't change, and pass the parts that do as parameters.