Uploading image with other parameters in SWIFT
<p>I want to upload image to server with other parameters using SWIFT and the server side script is in PHP. I'm posting the request to <a href="http://www.23look.com/merchant/verify" rel="nofollow">http://www.23look.com/merchant/verify</a> which accepts following parameters:</p>

<p>mer_name - String</p>

<p>mer_tel - String</p>

<p>mer_address - string</p>

<p>lng - string</p>

<p>lat - string</p>

<p>mer_licence - file type</p>

<p>token - string</p>

<p>mer_type - string</p>

<p>Whenever I make HTTP post request, it always returns 0 value in response, which means "System Error". Maybe there's something wrong I'm doing, can someone please help me see my code?</p>

<pre><code>func uploadImage()
{
    let postPictureUrl = NSURL(string: "http://www.23look.com/merchant/verify")
    let request = NSMutableURLRequest(URL: postPictureUrl!)
    request.HTTPMethod="POST"

    let param=[
        "mer_name" : shopNameUITF.text!,
        "mer_tel" : shopTelephoneUITF.text!,
        "mer_address" : shopAddressUITF.text!,
        "lat" : "39.6892",
        "lng" : "115.9239",
        "token": KeychainWrapper.stringForKey("tokenValue")!,
        "mer_type": "smalll"
    ]

    let abc =  KeychainWrapper.stringForKey("tokenValue")!

    let boundary = generateBoundaryString()

    request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")

    let imageData = UIImageJPEGRepresentation(myImageView.image!, 0.1)

    if imageData==nil { print("image data is nil"); return }

    request.HTTPBody = createBodyWithParameters(param, filePathKey: "mer_license", imageDataKey: imageData!, boundary: boundary)

    let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
        data, response, error in

        if error != nil {
            print("error=\(error)")
            return
        }

        //You can print out response object
        print("***** response = \(response)")

        // Print out reponse body
        let responseString = NSString(data: data!, encoding: NSUTF8StringEncoding)
        print("**** response data = \(responseString!)")

        do {

            let json = try NSJSONSerialization.JSONObjectWithData(data!, options: .MutableContainers) as? NSDictionary

            dispatch_async(dispatch_get_main_queue(), {
                print(NSString(data: data!, encoding:NSUTF8StringEncoding)!)
                print(json)
            })

        } catch let err {
            print(err)
        }
    }
    task.resume()
}

func generateBoundaryString() -&gt; String {
    return "Boundary-\(NSUUID().UUIDString)"
}

func createBodyWithParameters(parameters:[String:String]?, filePathKey: String?, imageDataKey:NSData, boundary: String) -&gt; NSData {

    var body=NSMutableData()

    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")
        }
    }

    let filename = "user-profile.jpg"
    let mimetype = "image/jpg"

    body.appendString("--\(boundary)\r\n")
    body.appendString("Content-Disposition: form-data; name=\"\(filePathKey!)\"; filename=\"\(filename)\"\r\n")
    body.appendString("Content Type: \(mimetype)\r\n\r\n")
    body.appendData(imageDataKey)
    body.appendString("\r\n")

    body.appendString("--\(boundary)--\r\n")

    return body
}  extension NSMutableData {
func appendString(string: String) {
    let data = string.dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)
    appendData(data!)
}
</code></pre>