等待不在猫鼬模型上工作 .findOne({email : req.body.email})

Question

我是新手，mongodb...我正在尝试使用 user.findOne({email}) 函数 returns 用户的电子邮件带有 await 关键字但节点js 抛出错误说

let user = await User.findOne({ email: req.body.email });
           ^^^^^

语法错误：await 仅在异步函数中有效

const express = require('express');
const User = require("../models/user");
const {body, validationResult} = require("express-validator");
const router = express.Router();

// Listening the request at assigned route
router.post('/', [
    // Validation array
    body("name", "Enter name").isLength({ min: 5 }),
    body("email", "Enter valid email").isEmail(),
    body("password", "password must not be less than 5").isLength({ min: 5 })

] ,

(req, res) => {

    // Errors in a single json...
    const errors = validationResult(req)

    // If there error return the error json...
    if (!errors.isEmpty()) {
        return res.status(400).json({ errors: errors.array() });
    }

    // Check if there any user with same email...
    let user = await User.findOne({ email: req.body.email });

    if (user) {
        return res.status(400).json({ error: "A user with this email already exist..."});
    }

    // Create user...
    // user = await User.create({
    //     name : req.body.name,
    //     email : req.body.email,
    //     password : req.body.password
    // })

    // res.json(user)
    res.send("Successful request...");
    
})

module.exports = router

Answer 1

使用关键字使回调函数异步

async (req, res) => {}

Answer 2

您只能在异步函数中使用 await。然后你可以写： (req, res) => { 像 async (req, res) => {.

另一种方法是不使用异步（但这也行），是使用回调函数： User.findOne({ email: req.body.email }).then((user)=>{ /* Your logic here */})

总的来说，我不想混淆async/callbacks，所以我坚持只使用异步或只使用回调:)

等待不在猫鼬模型上工作 .findOne({email : req.body.email})

await not working on mongoose model .findOne({email : req.body.email})

javascript

mongodb

node.js

mongoose-schema