How to send a POST request through Swift? - json

Question

I have my controller like this -
def create
if (#user = User.find_by_email(params[:email])) && #user.valid_password?(params[:password])
render json: #user.as_json(only: [:email,:authentication_token]),status: :created
else
render json:('Unauthorized Access')
end
end
When I use Postman to make this request, I choose Body, and form data and adds in the email and password. And this WORKS
How to use swift to do the same? This is what I have tried
let url = URL(string: "http://localhost:3000/api/v1/user_serialized/")
let config = URLSessionConfiguration.default
let request = NSMutableURLRequest(url: url!)
request.httpMethod = "POST"
let bodyData = "email=Test#test.com&password=Test1234"
request.httpBody = bodyData.data(using: String.Encoding.utf8);
let session = URLSession(configuration: config)
let task = session.dataTask(with: url! as URL, completionHandler: {(data, response, error) in
let json = JSON(data:data!)
debugPrint(json)
})
task.resume()

Answer 1

I have made a Custom HTTP class where we can sent url, parameter and we will get Data from API. Below is the class.
import Foundation
//HTTP Methods
enum HttpMethod : String {
case GET
case POST
case DELETE
case PUT
}
class HttpClientApi: NSObject{
//TODO: remove app transport security arbitary constant from info.plist file once we get API's
var request : URLRequest?
var session : URLSession?
static func instance() -> HttpClientApi{
return HttpClientApi()
}
func makeAPICall(url: String,params: Dictionary<String, Any>?, method: HttpMethod, success:#escaping ( Data? ,HTTPURLResponse? , NSError? ) -> Void, failure: #escaping ( Data? ,HTTPURLResponse? , NSError? )-> Void) {
request = URLRequest(url: URL(string: url)!)
logging.print("URL = \(url)")
if let params = params {
let jsonData = try? JSONSerialization.data(withJSONObject: params, options: .prettyPrinted)
request?.setValue("application/json", forHTTPHeaderField: "Content-Type")
request?.httpBody = jsonData//?.base64EncodedData()
//paramString.data(using: String.Encoding.utf8)
}
request?.httpMethod = method.rawValue
let configuration = URLSessionConfiguration.default
configuration.timeoutIntervalForRequest = 30
configuration.timeoutIntervalForResource = 30
session = URLSession(configuration: configuration)
//session?.configuration.timeoutIntervalForResource = 5
//session?.configuration.timeoutIntervalForRequest = 5
session?.dataTask(with: request! as URLRequest) { (data, response, error) -> Void in
if let data = data {
if let response = response as? HTTPURLResponse, 200...299 ~= response.statusCode {
success(data , response , error as? NSError)
} else {
failure(data , response as? HTTPURLResponse, error as? NSError)
}
}else {
failure(data , response as? HTTPURLResponse, error as? NSError)
}
}.resume()
}
}
Now you can refer below code to get how to make an API call.
var paramsDictionary = [String:Any]()
paramsDictionary["username"] = "BBB"
paramsDictionary["password"] = "refef"
HttpClientApi.instance().makeAPICall(url: "Your URL", params:paramsDictionary, method: .POST, success: { (data, response, error) in
// API call is Successfull
}, failure: { (data, response, error) in
// API call Failure
})

Answer 2

I think you should pass your request instead of the url to session.dataTask
here is how my code looks like:
private let url = URL(string: "http://example.com/")!
func httpPost(jsonData: Data) {
if !jsonData.isEmpty {
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.httpBody = jsonData
URLSession.shared.getAllTasks { (openTasks: [URLSessionTask]) in
NSLog("open tasks: \(openTasks)")
}
let task = URLSession.shared.dataTask(with: request, completionHandler: { (responseData: Data?, response: URLResponse?, error: Error?) in
NSLog("\(response)")
})
task.resume()
}
}

Answer 3

Here is the Example of POST API for calling Login API with parameters "emailaddress" and "password" with userEmailID and Userpassword as two strings holding values for email and password respectively.
You can call this POST API anywhere in your view controller, as given below:
self.postLoginCall(url: "Your post method url") example: self.postLoginCall(url: "http://1.0.0.1/api/login.php")
func postLoginCall(url : String){
let request = NSMutableURLRequest(url: NSURL(string: url)! as URL)
request.httpMethod = "POST"
let postString = "emailaddress=\(userEmailID!)&password=\(Userpassword!)"
print(postString)
request.setValue("application/x-www-form-urlencoded; charset=utf-8", forHTTPHeaderField: "Content-Type")
request.httpBody = postString.data(using: String.Encoding.utf8)
let task = URLSession.shared.dataTask(with: request as URLRequest) { data, response, error in
guard error == nil && data != nil else { // check for fundamental networking error
print("error=\(error)")
return
}
do {
if let responseJSON = try JSONSerialization.jsonObject(with: data!) as? [String:AnyObject]{
print(responseJSON)
print(responseJSON["status"]!)
self.response1 = responseJSON["status"]! as! Int
print(self.response1)
//Check response from the sever
if self.response1 == 200
{
OperationQueue.main.addOperation {
//API call Successful and can perform other operatios
print("Login Successful")
}
}
else
{
OperationQueue.main.addOperation {
//API call failed and perform other operations
print("Login Failed")
}
}
}
}
catch {
print("Error -> \(error)")
}
}
task.resume()
}

Answer 4

Hello everyone I share below an example of a function to make a request in POST with SWIFT 5+.
This function allows you to send a POST request with an API entry point and parameters in the form of [[String: String]] and an Int to determine the output action.
For the output actions we call a function with Switch Case.
The operation is extremely simple. You have to put the two functions in one of your classes.
func MGSetRequestApi(endpoint: String, parameters: [[String: String]], MGSetAction: Int) -> String {
var setReturn: String!
let semaphore = DispatchSemaphore (value: 0)
var MGGetParam: String! = ""
for gate in parameters {
for (key, value) in gate {
let myParam = key + "=" + value + "&"
MGGetParam.append(contentsOf: myParam)
}
}
let postData = MGGetParam.data(using: .utf8)
var request = URLRequest(url: URL(string: endpoint)!,timeoutInterval: 10000)
request.addValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
request.httpMethod = "POST"
request.httpBody = postData
let task = URLSession.shared.dataTask(with: request) { data, response, error in
guard let data = data else {
print(String(describing: error))
semaphore.signal()
return
}
print(String(data: data, encoding: .utf8)!)
setReturn = String(data: data, encoding: .utf8)!
DispatchQueue.main.async {
self.MGRequestAction(MGGetIdRq: MGSetAction, MGGetData: setReturn)
}
semaphore.signal()
}
task.resume()
semaphore.wait()
return setReturn
}
Then implement this function to manage the outputs
func MGRequestAction(MGGetIdRq: Int, MGGetData: String) {
switch MGGetIdRq {
case 1:
// Do something here
case 2:
// Do something else here
case 3:
// Do something else here again
default:
print("Set default action");
}
}
How to use this, you have two possibilities, the first one is to process what the function
MGSetRequestApi(endpoint: String, parameters: [[String: String]], MGSetAction: Int) -> String
returns (String) or to pass by the function
MGRequestAction(MGGetIdRq: Int, MGGetData: String)
which will call your Json parse function.
The MGRequestAction() function takes for parameter an Int for the choice of the action and the String of the return of the request
Now to use it do like this:
_ = MGSetRequestApi(endpoint: MY_END_POINT_API,
parameters: [["KEY_1": "VALUE 1"],
["KEY_2": "VALUE 2"],
["KEY_3": "VALUE 3"],
["KEY_4": "VALUE 4"]],
MGSetAction: 3)