如何在Swift中找到创建多部分/表单请求失败的地方?

我正在尝试用Swift上传一个文件,但我认为我无法构建正确的httpBody,我似乎无法找到它的位置。

我在iPhone模拟器上获取一个文件,将其内容加载到一个数据变量中,然后构建一个URLRequest,它应该发送 用户名 , 暗语 ,以及 文件名 以及它的内容。

响应是200,我的服务器记录如何调用正确的Perl脚本,但非常简单的脚本(在命令行中测试)看不到头。而且,我在URLSession中没有发现错误。

我已经检查了请求变量,据我所知,它似乎是正确的。

如果有人能发现我哪里出了问题,或者我应该在哪里寻找错误。

以下是: URLRequest正文和我的示例应用程序的完整代码

请求主体 如调试器中所示

http://example.com/cgi-bin/swift.pl
url:可选
一些: http://example.com/cgi-bin/swift.pl
_网址: http://example.com/cgi-bin/swift.pl
缓存策略:0
timeoutInterval:60.0
main文档URL:nil

networkServiceType:u C.NSURLRequestNetworkServiceType

AllowCellularAccess:正确
httpMethod:可选
一些:“帖子”
所有HttpHeaderFields:可选<字典<弦,弦>>
一些:1个元素
0:2个元素
关键字:“ContentType”
值:“多部分/formdata;边界=边界E8B0434637F341F0962215B412B61FAA”
httpBody: 可选择的
部分:27075字节
计数:27075
指针:0x00007f9d15c00000
pointerValue:140312651497472
httpBodyStream:无
httpShouldHandleCookies:没错

HttpShouldUsePipeline:错误

示例应用程序

import UIKit
import MobileCoreServices

typealias Params = [String: String]

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        let myButton = UIButton(frame: CGRect(origin: CGPoint(x: 100, y: 100), size: CGSize(width: 100, height: 50)))
        myButton.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)
        myButton.backgroundColor = .systemGray
        view.addSubview(myButton)
    }

   @objc func buttonAction(sender: UIButton!) {
        var params = [String: String]()
        
        params = ["username" : "John", "userid" : "13"]
        let fManager = FileManager.default
        guard let mainurl = fManager.urls(for: .documentDirectory, in: .userDomainMask).first else { print ("oh no");return;}

        print ("\(mainurl.path)")
        let myFile = mainurl.path + "/inv.xlsx"
        let upFile = XFile(filename: myFile, key: "filename")

        var components = URLComponents()
        components.scheme = "http"
        components.host = "example.com"
        components.path = "/cgi-bin/swift.pl"
    
        let url = components.url
        if url == nil { return }
        var request = URLRequest(url: url!)
        request.httpMethod = "POST"
        
        let boundary = generateBoundary()
        
        request.setValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")
        
        
        let dataBody = createDataBody(params: params, file: upFile, boundary: boundary)
        request.httpBody = dataBody
        
        let session = URLSession.shared
        session.dataTask(with: request)
//        session.uploadTask(with: request, from: request.httpBody)
        { (data, response, error) in
            if let response = response {
                print(response)
            }
        
        if let error = error {
            print(error)
        }
                        
            if let data = data {
                do {
                    let json = try JSONSerialization.jsonObject(with: data, options: [])
                    print(json)
                } catch {
                    print(error)
                }
            }
            }.resume()
        
    }
    
    func generateBoundary() -> String {
        return "Boundary-\(NSUUID().uuidString)"
    }
    
    func createDataBody(params: Params?, file: XFile?, boundary: String) -> Data {
        let lineBreak = "\r\n"
        var body = Data()
        
        if let parameters = params {
            for (key, value) in parameters {
                body.append("--\(boundary + lineBreak)")
                body.append("Content Disposition: form-data; name=\"\(key)\"\(lineBreak + lineBreak)")
                body.append("\(value + lineBreak)")
            }
        }
        
        if let xFile = file {
            body.append("--\(boundary + lineBreak)")
            body.append("Content Disposition: form-data; name=\"\(xFile.key)\"; filename=\"\(xFile.filename)\"\(lineBreak)")
            body.append("Content-Type: \(xFile.mimeType! + lineBreak + lineBreak)")
            body.append(xFile.data)
            body.append(lineBreak)
        }
        
        body.append("--\(boundary)--\(lineBreak)")
        
        return body
    }
}

extension Data {
    mutating func append(_ string: String) {
        if let data = string.data(using: .utf8) {
            append(data)
        }
    }
}

保存文件上传的结构

import UIKit
import MobileCoreServices

struct XFile {
    let key: String
    let filename: String
    let data: Data
    var mimeType: String?
    
    init?(filename: String, key: String) {
        let fileUrl = URL.init(fileURLWithPath: filename)
        
        
        self.key = key
        self.filename = "\(arc4random()).\(URL(fileURLWithPath: filename).pathExtension)"

        do {
            self.data = try Data(contentsOf: fileUrl)
        } catch { return nil}

        self.mimeType = mimeType(path: filename)
    }

    func mimeType(path: String) -> String {
            let pathExtension = URL(fileURLWithPath: path).pathExtension as NSString
            guard
                let uti = UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, pathExtension, nil)?.takeRetainedValue(),
                let mimetype = UTTypeCopyPreferredTagWithClass(uti, kUTTagClassMIMEType)?.takeRetainedValue()
            else {
                return "application/octet-stream"
            }
 
            return mimetype as String
        }
}