我目前正在创建网站的注册功能。 我正在使用 MEVN 堆栈，并且我已经设法让我的前端与我的数据库一起工作，但是一旦完成，我会得到一个
无法发布用户/注册
让我向您展示相关代码:
router.post('/signup', (req, res, next) => {
//Verify if user email is associated with an account.
User.find({email: req.body.email})
.exec()
.then(user => {
//Returns message if user email is associated with an account.
if(user.length >= 1) {
getCode.fourHundred(res, 409,
'This email is already associated with an account.');
} else { //If email is not found, makes a hashed password value.
if(req.body.password !== 'undefined') {
bcrypt.hash(req.body.password, 10, (err, hash) => {
if(err) {
getCode.fiveHundred(res, err);
} else {
//If no errors occur, creates a new user.
const user = new User({
_id: new mongoose.Types.ObjectId(),
firstName: req.body.firstName,
lastName: req.body.lastName,
email: req.body.email,
password: hash
});
// Saves user information to Database.
user.save()
.then(result => {
console.log(result);
getCode.twoHundred(res, 201, 'User created')
return res.redirect(301, 'localhost:8080')
})
.catch(getCode.fiveHundred(res, err))
}
});
}
}
});
});
我的前端如下:
<template>
<main class="container">
<h1> Sign Up</h1>
<form class="grid-container" action="/users/signup" method="POST">
<label class="label" for="first-name">First Name:</label>
<input
id="first-name"
type="text"
class="first-name input form-control"
placeholder="First Name"
v-model="firstName"
required>
<label class="label" for="last-name" >Last Name:</label>
<input id="last-name"
type="text"
class="last-name input form-control"
placeholder="Last Name"
v-model="lastName"
required>
<label class="label" for="email" >Email:</label>
<input id="email"
type="email"
class="email input form-control"
placeholder="example@example.com"
v-model="email"
required>
<label class="label" for="password">Password:</label>
<input id="password"
type="password"
class="password input form-control"
placeholder="Password"
v-model="password"
required>
<div class="button-grid">
<button
class="button"
type="submit"
@click="signUp">
Sign Up
</button>
</div>
</form>
</main>
</template>
<script>
import AuthenticationService from '@/services/AuthenticationService.js'
export default {
name: 'SignUp',
data () {
return {
firstName: '',
lastName: '',
email: '',
password: ''
}
},
methods: {
async signUp () {
const response = await AuthenticationService.signUp({
firstName: this.firstName,
lastName: this.lastName,
email: this.email,
password: this.password
})
console.log(response)
setTimeout(() => this.redirect(), 1000)
},
redirect () {
this.$router.push({ name: 'BuyAndSell' })
}
}
}
</script>
我正在使用 axios 将前端连接到后端。
export default () => axios.create({
baseURL: 'http://localhost:3000/'
})
import api from '@/services/api'
export default {
signUp (credentials, res) {
return api().post('/users/signup', credentials)
}
}
我尝试过通过 Vue 进行重定向，也尝试过通过 Express，但一无所获。
编辑:我还添加了此代码，因为这些是我重构以稍微清理代码的一些函数。
const getFiveHundredErrors = (res, err) => {
console.log(err);
return res.status(500).json({
error: err
});
};
const getfourHundredErrors = (res, code, message) => {
return res.status(code).json({
message: message
})
};
const getTwoHundredSuccessCodes = (res, code, output, token) => {
return res.status(code).json({
output: output,
token: token || null
})
}
module.exports = {
fiveHundred: getFiveHundredErrors,
fourHundred: getfourHundredErrors,
twoHundred: getTwoHundredSuccessCodes }
这是app.js 文件。 我的控制台出现 500 错误，这可能是 .catch() 中的错误，也许错误就在那里？但我不确定如何让代码在创建用户后重定向回主页。此外，即使正在创建用户，也不会向我显示 200 状态。
const express = require('express');
const morgan = require('morgan');
const bodyParser = require('body-parser');
const cors = require('cors');
const mongoose = require('mongoose');
const path = require('path');
const app = express();
const port = process.env.PORT || 3000;
const userRoutes = require('./api/routes/users');
const productRoutes = require('./api/routes/products');
const savedItemsRoutes = require('./api/routes/savedItems');
//I removed the mongodb.connect function to avoid exposing that info, even though I have the password stored in a .env file.
//Middleware.
app.use(morgan('dev'))
app.use('/uploads', express.static('uploads'))
app.use(bodyParser.urlencoded({extended: false}));
app.use(bodyParser.json());
app.use(cors());
app.use((req, res, next) => {
res.header('Access-Control-Allow-Origin', '*');
res.header('Access-Control-Allow-Headers',
'Origin, X-Requested-Width, Content-Type, Accept, Authorization'
);
if(req.method === 'OPTIONS') {
res.header('Access-Control-Allow-Methods',
'PUT', 'POST', 'PATCH', 'DELETE', 'GET');
return res.status(200/json({}));
}
next();
});
// Request Handling Routes.
app.use('/users', userRoutes);
app.use('/products', productRoutes);
app.use('/savedItems', savedItemsRoutes);
其他问题: 我有点明白这里发生了什么，但我不确定在哪里可以解决它。我知道一旦发送原始响应，我必须返回一些 res.status，但我只是对我的代码流程有点困惑，我试图跟踪错误消息将我带到哪里，但此时我只是无能为力。
(node:28036) UnhandledPromiseRejectionWarning: Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
at ServerResponse.setHeader (_http_outgoing.js:535:11)
at ServerResponse.header (/Users/edgarnegron/Projects/llevatelopr/server/node_modules/express/lib/response.js:771:10)
at ServerResponse.send (/Users/edgarnegron/Projects/llevatelopr/server/node_modules/express/lib/response.js:170:12)
at ServerResponse.json (/Users/edgarnegron/Projects/llevatelopr/server/node_modules/express/lib/response.js:267:15)
at getTwoHundredSuccessCodes (/Users/edgarnegron/Projects/llevatelopr/server/api/routes/users.js:112:20)
at /Users/edgarnegron/Projects/llevatelopr/server/api/routes/users.js:40:17
at processTicksAndRejections (internal/process/task_queues.js:97:5)
最佳答案
问题在于表单操作会将您带离 SPA 并进入错误的路线。实际上，您在表单提交上做了两件事:
1) 单击操作调用 signUp 方法。这正在创建用户，尽管我们看不到服务代码。
2)表单操作
这是一个糟糕的设计，原因有两个。您不应该像这样生成 2 个单独的调用，也不应该以这种方式使用表单操作，否则您将离开单页应用程序。还有前端和后端重定向。完全删除表单操作/方法。这就是让您远离 SPA(并进入显示错误消息的错误路线)的原因。一般来说，您不会将表单操作与 SPA 一起使用，因为它会让您离开应用程序。
问题 2
将保存后代码更改为:
user.save()
.then(result => {
return res.status(201).send(result);
})
这将设置状态并发送回您刚刚创建的用户，只要 save 也返回它。不需要 301。
关于node.js - MEVN Stack 启动后重定向至主页，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/60360988/