Swift upload file via WCF - swift

Question

I've been fighting this for over 10 hours and done my best before coming here. Many tutorials I've looked out ended up being outdated by a version or two and/or missing some key knowledge in the explanation.
I'm trying to upload a PDF to a server using a WCF Rest Service. When I debug on the WCF service, the variable named document is a null stream. I've searched the web many hours trying many different things and I've exhausted MANY attempts to get such a little thing to work! What is really annoying is that this isn't the first time someone has needed to do this and yet I haven't found an answer anywhere.
If there is a better way to post the PDF other than what I've posted, I'm open to suggestions but I don't want to use third-party frameworks.
Requirements:
- Using the WCF service is required
- I'm not saving to a file system or UNC
I need to get a valid memory stream passed to the service and I can take care of the function code from there. I've tried using a Base64DataString before this and I could get that to work either. If you wanted to provide that as an option, I'm open to it.
Please help!
Swift 4 code:
import PDFKit
class FileUpload {
static func generateBoundaryString() -> String {
return "Boundary-\(UUID().uuidString)"
}
static func dataUploadBodyWithParameters(_ parameters: [String: Any]?, filename: String, mimetype: String, dataKey: String, data: Data, boundary: String) -> Data {
var body = Data()
// encode parameters first
if parameters != nil {
for (key, value) in parameters! {
body.appendString("--\(boundary)\r\n")
body.appendString("Content-Disposition: form-data; name=\"\(key)\"\r\n\r\n")
body.appendString("\(value)\r\n")
}
}
body.appendString("--\(boundary)\r\n")
body.appendString("Content-Disposition: form-data; name=\"\(dataKey)\"; filename=\"\(filename)\"\r\n")
body.appendString("Content-Type: \(mimetype)\r\n\r\n")
body.append(data)
body.appendString("\r\n")
body.appendString("--\(boundary)--\r\n")
print(body)
return body
}
static func uploadData(_ data: Data, toURL urlString: String, withFileKey fileKey: String, completion: ((_ success: Bool, _ result: Any?) -> Void)?) {
if let url = URL(string: urlString) {
// build request
let boundary = generateBoundaryString()
var request = URLRequest(url: url)
request.httpMethod = "POST"
request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
request.setValue("application/json", forHTTPHeaderField: "Accept")
// build body
let body = dataUploadBodyWithParameters(nil, filename: "iOSUpload.pdf", mimetype: "application/pdf", dataKey: fileKey, data: data, boundary: boundary)
request.httpBody = body
//UIApplication.shared.isNetworkActivityIndicatorVisible = true
URLSession.shared.dataTask(with: request, completionHandler: { (data, response, error) -> Void in
if data != nil && error == nil {
do {
let result = try JSONSerialization.jsonObject(with: data!, options: [])
print(result)
DispatchQueue.main.async(execute: { completion?(true, result) })
} catch {
DispatchQueue.main.async(execute: { completion?(false, nil) })
}
} else { DispatchQueue.main.async(execute: { completion?(false, nil) }) }
//UIApplication.shared.isNetworkActivityIndicatorVisible = false
}).resume()
} else { DispatchQueue.main.async(execute: { completion?(false, nil) }) }
}
}
extension Data {
mutating func appendString(_ string: String) {
let data = string.data(using: String.Encoding.utf8, allowLossyConversion: true)
append(data!)
}
}
}
WCF Relevant Code:
<ServiceContract>
Public Interface IWebService
<OperationContract>
<WebInvoke(Method:="POST", UriTemplate:="UploadFile/{fileName}")>
Function UploadFile(fileName As String, document As Stream) As String
End Interface
<ServiceBehavior(InstanceContextMode:=InstanceContextMode.Single)>
Public Class MyWebService : Implements IWebService
Public Function UploadFile(fileName As String, document As Stream) As String Implements IWebService.UploadFile
'document is null
End Function