axios post请求报错400是什么原因？

Question

I am writing a cli in oclif that consumes data from a rest api written in node.js. I am trying to perform a post request that sends username and password, receives a token from the api and verifies it.

My code is the following in the file (Login.ts):

import Command from '@oclif/command'
import axios from 'axios'
import {flags} from  '@oclif/command'
const bcrypt = require('bcrypt');
process.env["NODE_TLS_REJECT_UNAUTHORIZED"] = 0;
export class LoginCommand extends Command {
  static flags = { 
    user: flags.string({dependsOn:['passw']}),
    //email: flags.string({dependsOn:['passw'],exlucsive:['user']}),
    passw: flags.string()
  }

  async run() {
        const {flags} = this.parse(LoginCommand); 
        var hash = bcrypt.hashSync(`${flags.passw}`,10);
        var fs=require('fs');
        var privateKey = fs.readFileSync('private.key');
        const token=await axios.post('https://localhost:8765/energy/api/Login?username=' +`${flags.user}` +'&passw=' + hash);
        jwt.verify(JSON.stringify(token),privateKey,function(err,decoded){
            fs.writeFileSync('softeng19bAPI.token',JSON.stringify(token));
        });

My code in the file (entry.routes.js):

app.post("/energy/api/Login", function(req,res){ 
        var jwt=require('jsonwebtoken');
        var password,e,a,q,p;
        sql.query(`SELECT user,pass,quota,apikey,email FROM users WHERE user=?`,[req.query.username],(err,res1) => {
            console.log(res1);
            password=res1[0].pass;
            e=res1[0].email;
            a=res1[0].apikey;
            q=res1[0].quota;
            p=res1[0].privileges;
        });
        if(req.query.passw = password){
                var jwt=require('jsonwebtoken');
                var privateKey = fs.readFileSync('/home/vangelis/softeng/energy/private.key');
                var token = jwt.sign({user:req.query.user ,passw: req.query.passw,email: e, quota: q,apikey: a,privileges: p }, privateKey, { algorithm: 'RS256' });
                res.status(200).send(token);
            }
        else res.status(400).send("Bad Request");
  });
  }

I think this error is usually produced with axios post requests, but I can't find were the error occurs.

Answer 1

Problem :

sql.query is callback type execution, meaning code-block with

if(req.query.passw = password)

would be executed before

password=res1[0].pass;

such as it is(presumably) asynchronous.

The problem of 400 (mentioned in comments to the post) is the usage of the assignment( = ) and not comparison( === ), so code inside if would be exactly like

if(req.query.passw = undefined)

which is falsy , so a decision would move to else branch

A Simple solution for this code:

move if-else inside callback of sql.query

PS falsy - assigning a value to a variable would return this value and in your case it is undefined ; to check this simply open Chrome's Console and execute 2 different cases:

var a = 1 // 1
var b = undefined // undefined