Вам необходимо преобразовать его в данные, подобные этим
guard let data = try? Data(contentsOf:fileUrl) else { return }
и загрузите как составную часть с Alamofire
Alamofire.upload(multipartFormData: { multipartFormData in
// use this
multipartFormData.append(data, withName: "audio", fileName: "audio.aac", mimeType: "audio/aac")
// or this
multipartFormData.append(fileUrl, withName: "audio", fileName: "audio.aac", mimeType: "audio/aac")
} ,to: url,method:.post,
headers:head,
encodingCompletion: { encodingResult in
switch encodingResult {
case .success(let upload, _, _):
upload.uploadProgress(closure: { (Progress) in
print("Upload Progress: \(Progress.fractionCompleted)")
})
upload.responseJSON { response in
}
break
case .failure(let encodingError):
break
}
})