RapidAPI-Translate

import Foundation

let headers = [
    "x-rapidapi-host": "google-translate1.p.rapidapi.com",
    "x-rapidapi-key": "78767832e6mshd1b6d5b2fa681a2p1229e3jsn09a1a1972cad",
    "accept-encoding": "application/gzip",
    "content-type": "application/x-www-form-urlencoded"
]

let postData = NSMutableData(data: "source=en".data(using: String.Encoding.utf8)!)
postData.append("&q=Hello, world!".data(using: String.Encoding.utf8)!)
postData.append("&target=es".data(using: String.Encoding.utf8)!)

let request = NSMutableURLRequest(url: NSURL(string: "https://google-translate1.p.rapidapi.com/language/translate/v2")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
    if (error != nil) {
        print(error)
    } else {
        let httpResponse = response as? HTTPURLResponse
        print(httpResponse)
    }
})

dataTask.resume()