Upload an .XML file with a name via POST method in SWIFT - swift

Question

As part of an HTTP server request I need to upload an .XML file in a POST request that includes query information. Yet simply using URLSession.shared.uploadTask(with:, fromFile:) doesn't seem to work. Like the following:
func reportRequest(url: URL) -> Void {
let fileURL: URL = URL(fileURLWithPath: ".../search_xml.xml")
var urlRequest = URLRequest(url: url)
urlRequest.httpMethod = "POST"
urlRequest.setValue(authToken, forHTTPHeaderField: "authorization")
let task = URLSession.shared.uploadTask(with: urlRequest, fromFile: fileURL) {data, response, error in
print(String(data: data!, encoding: .utf8)!)
print(response)
}
task.resume()
I have achieved this on Python using the files parameters in the requests module, and passing a dictionary in it like the following:
headers = {'authorization': authToken, }
files = {'xmlRequest': open('.../search.xml', 'rb')}
response = requests.post(url, headers=headers, files=files)
I also achieved this in RestMan (a browser extension to manage REST APIs) by adding a form data in the body, with "xmlRequest" as key and choosing the .XML file as value.
It might seem like I have to build request body myself in SWIFT, but I have little knowledge in that, and the tutorials I find about it are mostly about uploading Images, which might be different.
Thanks in advance!

Answer 1

Here's a generic example to upload a file.
let headers = [
"content-type": "multipart/form-data;",
"authorization": "authToken",
]
let parameters = [
[
"name": "xmlfile",
"fileName": "search_xml.xml"
]
]
var body = ""
var error: NSError? = nil
for param in parameters {
let paramName = param["name"]!
body += "--\(boundary)\r\n"
body += "Content-Disposition:form-data; name=\"\(paramName)\""
if let filename = param["fileName"] {
let contentType = param["content-type"]!
let fileContent = String(contentsOfFile: filename, encoding: String.Encoding.utf8)
if (error != nil) {
print(error)
}
body += "; filename=\"\(filename)\"\r\n"
body += "Content-Type: \(contentType)\r\n\r\n"
body += fileContent
} else if let paramValue = param["value"] {
body += "\r\n\r\n\(paramValue)"
}
}
let request = NSMutableURLRequest(url: NSURL(string: "https://example.com/fileupload")! as URL,
cachePolicy: .useProtocolCachePolicy,
timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data
let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
if (error != nil) {
print(error)
} else {
let httpResponse = response as? HTTPURLResponse
print(httpResponse)
}
})
dataTask.resume()