How to make this POST request with different objects? - json

Question

Overview:
I am trying to make a POST request, which I have done before with only strings. This time, I have a few variables, being: String, Int, and Bool.
Error:
Cannot assign value of type [String : Any] to type Data
Line causing the error:
request.httpBody = paramToSend
Question:
How to convert a Dictionary into Data ?
Complete Code:
func sendComplimentAPI (message: String, recipient: Int, isPublic: Bool) {
let url = URL(string: "https://complimentsapi.herokuapp.com/compliments/send/")
let session = URLSession.shared
let preferences = UserDefaults.standard
let request = NSMutableURLRequest(url: url!)
request.addValue("\(preferences.object(forKey: "token") as! String)", forHTTPHeaderField: "Authorization")
request.httpMethod = "POST"
let paramToSend = ["message":message,"recipient":recipient,"is_public":isPublic] as [String : Any]
request.httpBody = paramToSend
let task = session.dataTask(with: request as URLRequest, completionHandler: {
(data, response, error) in
guard let _:Data = data else {return}
let json:Any?
do{json = try JSONSerialization.jsonObject(with: data!, options: [])}
catch {return}
guard let server_response = json as? NSDictionary else {return}
if let session_data = server_response["id"] as? String {
print("worked")
//do something
/*DispatchQueue.main.async (
execute:
)*/
} else {
print("error")
}
})
task.resume()
}
EDIT:
I have tried this new code and it is still not posting to the server. I am attaching what I changed and also writing what the console shows for the two prints I have it do.
let paramToSend = ["message":writeTextField.text!,"recipient":1,"is_public":isPrivate] as [String : Any] //messageString + recipientString + isPublicString
do {
var serialized = try JSONSerialization.data(withJSONObject: paramToSend, options: .prettyPrinted)
print(serialized)
request.httpBody = serialized
print(request.httpBody)
} catch {
print("found a problem")
}
The console returns (for serialized and then the HTTP body):
113 bytes
Optional(113 bytes)
Is that optional causing the problem? How do I fix it?

Answer 1

To convert Dictionary to Data, use JSONSerialization.data:
Solution:
JSONSerialization.data(withJSONObject: paramToSend, options: .prettyPrinted)
Check the request:
Print the request and see if it matches your expectation
Reading the response:
//Check if there is any error (check if error != nil)
//Examine the response
let statusCode = (response as? HTTPURLResponse)?.statusCode
let statusCodeDescription = (response as? HTTPURLResponse)?.localizedString(forStatusCode: httpResponse.statusCode)
//Check Data
if let data = data {
let dataString = String(data: data, encoding: String.Encoding.utf8)
}

Answer 2

It turns out I needed to add a simple additional header to get the whole thing to work.
request.setValue("application/json", forHTTPHeaderField: "Content-Type")
This is probably why it was not understanding the dictionary I was sending it