Express.js UnhandledPromiseRejectionWarning:未处理的承诺被拒绝

时间:2020-08-17 12:35:30

标签: javascript node.js promise

所以我有以下代码:

app.post('/api/login', async function (req, res){
  try  {
    let [sorted,users] = await getSorted();
    const pw = req.body.password;
    const submittedUser = req.body.username;
    const hashedPassword = await bcrypt.hash(req.body.password, 10);
    // const user = { id: req.body.id, username: req.body.username, password: req.body.password };
    // USERNAME = FIRSTNAME
    var user = new User({firstname: req.body.username, eMail: req.body.eMail, password: hashedPassword });
    sorted.forEach(async ([firstname, password]) => {
      let result = bcrypt.compareSync(pw, password);
      // r = true if hash = hashed pw
      var serializeCookie = function(key, value, hrs) {
        // This is res.cookie’s code without the array management and also ignores signed cookies.
        if ('number' == typeof value) value = val.toString();
        if ('object' == typeof value) value = JSON.stringify(val);
        return cookie.serialize(key, value, { expires: new Date(Date.now() + 1000 * 60 * hrs), httpOnly: true });
      }; 

      var setMultipleCookies = function(res) {
        set_cookies.push(getCookie(access_token, myValue1.toString(), default_cookie_age));
        set_cookies.push(getCookie(loggedinid, myValue2.toString(), default_cookie_age));
        res.header("Set-Cookie", set_cookies);
      } 
      set_cookies = ['loggedinid', id]
      if (result === true && firstname == submittedUser) {
        jwt2.sign({user}, 'secrethere', { expiresIn: '15min'}, (err, token) =>{
          set_cookies.push('access_token'+ 'Bearer'+token).header("Set-Cookie", set_cookies)
                     .json(user);
        });
      }
      else {
        res.status(200).send("bad login");
      } 
    });    
  } catch (err) {
    res.status(500).send();
    console.log(err);
  }
});

我被抛出错误:

(node:6628) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:6628) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

我要完成的工作:

我的登录功能确实可以正常工作,然后才需要进行设置即可设置多个Cookie。我在这里找到了一个关于SO的问题,我再也找不到了,它表明存在一个错误和一些注释,它可能已得到修复,但由于代码无法正常工作,因此没有发现任何证据。因此,我不得不做这个黑客,我在代码中实现了它,并给了我这些错误。 set_cookies = ['loggedinid', id]应该获得第二个cookie作为键登录的id和值变量的id。 Id是MongoDB ID名称

1 个答案:

答案 0 :(得分:1)

至少这些问题:

  1. await回调中的任何地方都没有forEach,因此将回调标记为async毫无用处。删除该关键字,您将不会再收到未处理的诺言拒绝。更改:

    sorted.forEach(async ([firstname, password]) => {
    

    收件人:

    sorted.forEach(([firstname, password]) => {
    
  2. 以下语句引用了不存在的header属性:

    set_cookies.push('access_token'+ 'Bearer'+token).header("Set-Cookie", set_cookies)
               .json(user);
    

    push的返回值是一个整数,因此不能在其上调用.header()。这触发了异常。也许您打算在.header()上致电res

    set_cookies.push('access_token'+ 'Bearer'+token);
    res.header("Set-Cookie", set_cookies)
       .json(user);
    
  3. 此行中有一个未定义的变量id

    set_cookies = ['loggedinid', id]
    

    我真的不能在这里说出您的意图,但是您应该确保id已定义并具有适当的值

  4. 从未定义val中的变量serializeCookie。您可能打算使用value

还有其他与您的问题无关的问题,例如:

  1. 从不调用两个函数serializeCookiesetMultipleCookies

  2. 如果您确实打算使用serializeCookie,那么它在写入数据的方式上是非常不一致的。那里确实不应该进行任何类型检查if。它应该总是执行:

    value = JSON.stringify(value);
    

    该功能可能只是:

    var serializeCookie = function(key, value, hrs) {
        return cookie.serialize(key, JSON.stringify(value), 
               { expires: new Date(Date.now() + 1000 * 60 * hrs), httpOnly: true });
    };