Why is one version of my http POST body not working? - ios

Question

I am trying to send something to an API using POST. The post body is made up of x 2 properties.
If I create the post body as one long string:
let postBody = "ministryId=nameOfMinistryHere&personId=1005" and then encode the string as follows urlRequest.httpBody = postBody.data(using: String.Encoding.utf8) it works perfectly.
But I am trying to create the post as a dictionary and then pass it to the API, but can't get it to work.
let postBody = ["ministryId":"nameOfMinistry", "personId":"1005"]
do {
try urlRequest.httpBody = JSONSerialization.data(withJSONObject: postBody, options: .prettyPrinted)
} catch {
print("problems serializing data")
}
When I use the latter option I am getting a 400 error from the server.
What am I missing?
Thanks in advance.

Answer 1

URLComponents is the class for dealing with multiple parameters. Code snippet:
let postBody = ["ministryId":"nameOfMinistry", "personId":"1005"]
let urlComponents = URLComponents(string: myURL)
let urlRequest = URLRequest(url: urlComponents.url!)
// transform the dictionary into queryItems
urlComponents.queryItems = postBody.map { URLQueryItem(name: $0, value: $1) }
urlRequest.httpBody = urlComponents.percentEncodedQuery?.data(using: String.Encoding.utf8)

Answer 2

thecloud_of_unKnowing answer to your comment as it was long i am posting it here -:
HTTP headers can be mainly classified into two types: HTTP Request Header Whenever you type a URL into the address bar and try to access it, your browser sends an HTTP request to the server. The HTTP request header contains information in a text-record form, which includes particulars such as the type, capabilities and version of the browser that generates the request, the operating system used by the client, the page that was requested, the various types of outputs accepted by the browser, and so on. HTTP Response Header Upon receiving the request header, the Web server will send an HTTP response header back to the client. An HTTP response header includes information in a text-record form that a Web server transmits back to the client's browser. The response header contains particulars such as the type, date and size of the file sent back by the server, as well as information regarding the server.SO you are just sending extra information to your server to let it know what kind of request it will accept.
Content-type: application/json; charset=utf-8 designates the content to be in JSON format, encoded in the UTF-8 character encoding. Designating the encoding is somewhat redundant for JSON, since the default (only?) encoding for JSON is UTF-8. So in this case the receiving server apparently is happy knowing that it's dealing with JSON and assumes that the encoding is UTF-8 by default, that's why it works with or without the header.

Answer 3

Simply make a dictionary as follows:
let jsonBody = ["username": email, "password": password]
Then you can do something like this:
let request = NSMutableURLRequest(url: NSURL(string: "YOUR URL") as URL)
request.httpBody = try! JSONSerialization.data(withJSONObject: jsonBody, options: .prettyPrinted)
Hope that helps!