Axios错误：请求失败，状态码为400

Question

任何人都可以提供帮助，请我仍在学习React + Axios并因请求400失败而卡住。我确实用'http://localhost:3000/users/login'更改了axios发布'users / login'，但无法解决。我在带有身份验证的axios帖子中又传递了1个参数。

谢谢，我需要专家帮助我。

Login.js

import { login } from './UserFunctions'

class Login extends Component {
  constructor() {
    super()
    this.state = {
      email: '',
      password: '',
      errors: {}
    }

    this.onChange = this.onChange.bind(this)
    this.onSubmit = this.onSubmit.bind(this)
  }

  onChange(e) {
    this.setState({ [e.target.name]: e.target.value })
  }
  onSubmit(e) {
    e.preventDefault()

    const user = {
      email: this.state.email,
      password: this.state.password
    }

    login(user)
    .then(res => {
      if (res) {
        this.props.history.push(`/profile`)
      }
    })
    .catch(err => {
      console.log(err)
    })    
  }

  render() {
    return (
      <div className="container">
        <div className="row">
          <div className="col-md-6 mt-5 mx-auto">
            <form noValidate onSubmit={this.onSubmit}>
              <h1 className="h3 mb-3 font-weight-normal">Please sign in</h1>
              <div className="form-group">
                <label htmlFor="email">Email address</label>
                <input
                  type="email"
                  className="form-control"
                  name="email"
                  placeholder="Enter email"
                  value={this.state.email}
                  onChange={this.onChange}
                />
              </div>
              <div className="form-group">
                <label htmlFor="password">Password</label>
                <input
                  type="password"
                  className="form-control"
                  name="password"
                  placeholder="Password"
                  value={this.state.password}
                  onChange={this.onChange}
                />
              </div>
              <button
                type="submit"
                className="btn btn-lg btn-primary btn-block"
              >
                Sign in
              </button>
            </form>
          </div>
        </div>
      </div>
    )
  }
}

export default Login

UserFunctions.js

import axios from 'axios'

export const register = newUser => {
  return axios
    .post('users/register', {
      first_name: newUser.first_name,
      last_name: newUser.last_name,
      email: newUser.email,
      password: newUser.password
    })
    .then(response => {
      console.log('Registered')
    })
    .catch(err => {
      console.log(err)
    })
}

export const login = user => {
  return axios
    .post('users/login', {
      email: user.email,
      password: user.password
    })
    .then(response => {
      console.log(response.data.token);
      localStorage.setItem('usertoken', response.data)
      return response.data
    })
    .catch(err => {
      console.log(err)
    })
}

package.json

{
  "name": "client",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "axios": "^0.18.1",
    "jwt-decode": "^2.2.0",
    "react": "^16.5.2",
    "react-dom": "^16.5.2",
    "react-router-dom": "^5.0.0",
    "react-scripts": "1.1.5"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test --env=jsdom",
    "eject": "react-scripts eject"
  },
  "proxy": "http://localhost:5000/"
}

Users.js

const express = require('express')
const users = express.Router()
const cors = require('cors')
const jwt = require('jsonwebtoken')
const bcrypt = require('bcrypt')

const User = require('../models/User')
users.use(cors())

process.env.SECRET_KEY = 'secret'

users.post('/register', (req, res) => {
  const today = new Date()
  const userData = {
    first_name: req.body.first_name,
    last_name: req.body.last_name,
    email: req.body.email,
    password: req.body.password,
    created: today
  }

  User.findOne({
    where: {
      email: req.body.email
    }
  })
    //TODO bcrypt
    .then(user => {
      if (!user) {
        bcrypt.hash(req.body.password, 10, (err, hash) => {
          userData.password = hash
          User.create(userData)
            .then(user => {
              res.json({ status: user.email + 'Bcrypt Registered!' })
            })
            .catch(err => {
              res.send('error: ' + err)
            })
        })
      } else {
        res.json({ error: 'User already exists' })
      }
    })
    .catch(err => {
      res.send('error: ' + err)
    })
})

users.post('/login', (req, res) => {
  User.findOne({
    where: {
      email: req.body.email
    }
  })
    .then(user => {
      if (user) {
        bcrypt.compare(req.body.password, hash, function(err, res) {
          if(res) {
            console.log('User Logged Successfully')
            let token = jwt.sign(user.dataValues, process.env.SECRET_KEY, {
              expiresIn: 1440
            })
            res.send(token)
          } else {
            console.log('Username / Password Wrong')
          } 
        });        
      } else {
        res.status(400).json({ error: 'User does not exist' })
      }
    })
    .catch(err => {
      res.status(400).json({ error: err })
    })
})

users.get('/profile', (req, res) => {
  var decoded = jwt.verify(req.headers['authorization'], process.env.SECRET_KEY)

  User.findOne({
    where: {
      id: decoded.id
    }
  })
    .then(user => {
      if (user) {
        res.json(user)
      } else {
        res.send('User does not exist')
      }
    })
    .catch(err => {
      res.send('error: ' + err)
    })
})

module.exports = users