Upload method slightly changed in Alamofire 5

func upload(image: Data, to url: Alamofire.URLRequestConvertible, params: [String: Any]) {
    AF.upload(multipartFormData: { multiPart in
        for (key, value) in params {
            if let temp = value as? String {
                multiPart.append(temp.data(using: .utf8)!, withName: key)
            }
            if let temp = value as? Int {
                multiPart.append("\(temp)".data(using: .utf8)!, withName: key)
            }
            if let temp = value as? NSArray {
                temp.forEach({ element in
                    let keyObj = key + "[]"
                    if let string = element as? String {
                        multiPart.append(string.data(using: .utf8)!, withName: keyObj)
                    } else
                        if let num = element as? Int {
                            let value = "\(num)"
                            multiPart.append(value.data(using: .utf8)!, withName: keyObj)
                    }
                })
            }
        }
        multiPart.append(image, withName: "file", fileName: "file.png", mimeType: "image/png")
    }, with: url)
        .uploadProgress(queue: .main, closure: { progress in
            //Current upload progress of file 
            print("Upload Progress: \(progress.fractionCompleted)")
        })
        .responseJSON(completionHandler: { data in
            //Do what ever you want to do with response
        })
}

Hope this will help you

EDIT: In case you don't quite get the above, here is an expansion:

let uploadRequest: UploadRequest = AF.upload(multipartFormData: multipartFormData, with: ...)
let completionHander: (AFDataResponse<Any>) -> Void) = { result in
    //Do what ever you want to do with response, which is a DataResponse<Success, AFError>
}
// Adds that completion hander to the UploadRequest
uploadRequest.responseJSON(completionHandler: completionHander)

This Is work for me Using Swift 4.2 Please try this

let url = "http://google.com" /* your API url */

let headers: HTTPHeaders = [
    /* "Authorization": "your_access_token",  in case you need authorization header */
    "Content-type": "multipart/form-data"
]

Alamofire.upload(multipartFormData: { (multipartFormData) in
    for (key, value) in parameters {
        multipartFormData.append("\(value)".data(using: String.Encoding.utf8)!, withName: key as String)
    }
    
    if let data = imageData{
        multipartFormData.append(data, withName: "image", fileName: "image.png", mimeType: "image/png")
    }
    
}, usingThreshold: UInt64.init(), to: url, method: .post, headers: headers) { (result) in
    switch result{
    case .success(let upload, _, _):
        upload.responseJSON { response in
            print("Succesfully uploaded")
            if let err = response.error{
                onError?(err)
                return
            }
            onCompletion?(nil)
        }
    case .failure(let error):
        print("Error in upload: \(error.localizedDescription)")
        onError?(error)
    }
}

This how I upload images and videos from a swift 5 app with Alamofire 5.

Images

    /**
     Send Image to server
     */

    func Post(imageOrVideo : UIImage?){  

    let headers: HTTPHeaders = [
        /* "Authorization": "your_access_token",  in case you need authorization header */
        "Content-type": "multipart/form-data"
    ]


        AF.upload(
            multipartFormData: { multipartFormData in
                multipartFormData.append(imageOrVideo!.jpegData(compressionQuality: 0.5)!, withName: "upload_data" , fileName: "file.jpeg", mimeType: "image/jpeg")
        },
            to: "http://ip.here.--.--/new.php", method: .post , headers: headers)
            .response { resp in
                print(resp)               

        }
}

You can create a temporary resource and use the temporary url (good for videos):

/**
 Send video to server
 */
func PostVideoUrl(url : URL){

    let headers: HTTPHeaders = [
        "Content-type": "multipart/form-data"
    ]        

    AF.upload(
        multipartFormData: { multipartFormData in
            multipartFormData.append(url, withName: "upload_data" , fileName: "movie.mp4", mimeType: "video/mp4")
    },
        to: "http://ip.here.--.--/newVideo.php", method: .post , headers: headers)
        .response { resp in
            print(resp)

    }

}