statusCode should be 200, but is 415

Question

I am trying to post a simple string, but I continuously getting the HTTP 415 Unsupported Media Type Error. I tried converting the parameter to JSON still it didn't work.

Method Updated

func requestUsingPostMethod(url: String, parameter: String, completion: @escaping (_ success: [String : AnyObject]) -> Void) {

    //@escaping...If a closure is passed as an argument to a function and it is invoked after the function returns, the closure is @escaping.

    var request = URLRequest(url: URL(string: url)!)
    request.addValue("application/json", forHTTPHeaderField: "Content-Type")
    request.addValue("application/json", forHTTPHeaderField: "Accept")
    request.httpMethod = "POST"
    let postString = parameter


    request.httpBody = try? JSONSerialization.data(withJSONObject: [postString])
      //  request.httpBody = postString.data(using: .utf8)
    let task = URLSession.shared.dataTask(with: request) { Data, response, error in

        guard let data = Data, error == nil else {  // check for fundamental networking error

            print("error=\(String(describing: error))")
            return
        }

        if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {  // check for http errors

            print("statusCode should be 200, but is \(httpStatus.statusCode)")
            print(response!)
            return

        }

        let responseString  = try! JSONSerialization.jsonObject(with: data, options: .allowFragments) as! [String : AnyObject]
        completion(responseString)


    }

    task.resume()

}

Request

NetworkCall().requestUsingPostMethod(url: "http://192.168.50.119:8181/rest/items/wemo_lamp_switch", parameter: "ON", completion: { response in

            print("--------------------------------------------------------------")
            print(response)
           // let jsonResults = JSON(String: response)
        })

ERROR

statusCode should be 200, but is 415 { URL: http://192.168.50.119:8181/rest/items/wemo_lamp_switch } { status code: 415, headers { "Content-Length" = 282; "Content-Type" = "application/json"; Date = "Tue, 12 Sep 2017 08:33:16 GMT"; Server = "Jetty(9.2.19.v20160908)"; } }

I Updated the question with your answers but still getting the same error.

Postman Data

{
    "id": "6f5d4f8a-612a-10f9-71b5-6dc8ba668885",
    "name": "simpledata",
    "description": "",
    "order": [
        "65df8736-1069-b0f0-3a1d-c318ce1810e0"
    ],
    "folders": [],
    "folders_order": [],
    "timestamp": 1505208950131,
    "owner": 0,
    "public": false,
    "requests": [
        {
            "id": "65df8736-1069-b0f0-3a1d-c318ce1810e0",
            "headers": "",
            "headerData": [],
            "url": "http://192.168.50.119:8181/rest/items/wemo_lamp_switch",
            "queryParams": [],
            "pathVariables": {},
            "pathVariableData": [],
            "preRequestScript": null,
            "method": "POST",
            "collectionId": "6f5d4f8a-612a-10f9-71b5-6dc8ba668885",
            "data": [],
            "dataMode": "raw",
            "name": "http://192.168.50.119:8181/rest/items/wemo_lamp_switch",
            "description": "",
            "descriptionFormat": "html",
            "time": 1505208951279,
            "version": 2,
            "responses": [],
            "tests": null,
            "currentHelper": "normal",
            "helperAttributes": {},
            "rawModeData": "OFF"
        }
    ]
}

Answer 1

Set your request's Content-Type header to whatever you expect your API to return. If you're sure that it returns a JSON then

request.allHTTPHeaderFields["Content-Type"] = "application/json"

Answer 2

request.addValue("application/json", forHTTPHeaderField: "Content-Type")
request.addValue("application/json", forHTTPHeaderField: "Accept")

Also

let theparam = JSONSerialization.data(withJSONObject: parameter)

Answer 3

You are sending a UTF8 encoded String instead of a JSON to the API, hence HTTP error 415. However, a simple String cannot be converted to JSON, it either needs to be part of an array or a dictionary, so you need to figure out the actual format your API is expecting.

request.httpBody = try? JSONSerialization.data(withJSONObject: [postString])

You might also need to add the Content-Type header to your HTTP headers.

request.allHTTPHeaderFields["Content-Type"] = "application/json"