(Swift 3,4,5...) Duplicate curl -u user:password with Chilkat HTTP

Demonstrates how to duplicate a curl command that uses the -u username:password option. (This assumes HTTP Basic Authentication, and Chilkat requires Basic authentication to be over a TLS connection.)

Duplicates the following curl command:

curl https://api.sandbox.paypal.com/v1/oauth2/token \
  -H "Accept: application/json" \
  -H "Accept-Language: en_US" \
  -u "Client-Id:Secret" \
  -d "grant_type=client_credentials"

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    let http = CkoHttp()!
    let req = CkoHttpRequest()!

    // The AddHeader method corresponds to the curl "-H" argument.
    req.addHeader("Accept", value: "application/json")
    req.addHeader("Accept-Language", value: "en_US")

    // The curl "-d" argument specifies the HTTP request body.  In this case,
    // we're sending an application/x-www-form-urlencoded request, and therefore
    // the body contains the URL-encoded query parameters.
    req.addParam("grant_type", value: "client_credentials")

    http.login = "PAYPAL_REST_API_CLIENT_ID"
    http.password = "PAYPAL_REST_API_SECRET"

    // Sends a POST request where the Content-Type is application/x-www-form-urlencoded
    var resp: CkoHttpResponse? = http.postUrlEncoded("https://api.sandbox.paypal.com/v1/oauth2/token", req: req)
    if http.lastMethodSuccess != true {
        print("\(http.lastErrorText!)")
        return
    }

    if resp!.statusCode.intValue != 200 {
        print("Error status code: \(resp!.statusCode.intValue)")
        print("\(resp!.bodyStr!)")
        resp = nil
        return
    }

    // The JSON response is in the resp BodyStr property
    print("\(resp!.bodyStr!)")
    print("-- Success.")

    resp = nil

}