My sent data using axios is returned in config, not data

Question

I am building my web app on NextJS NodeJS and Express, I am running two servers on localhost 3000 for next and 9000 for express.

I have a form with two input fields and I am sending the state with axios post to the url with data, on the server-side I am receiving that request and sending back the same received data as a response.

I get the response from server with data: success and my data in config.data

Why is my data in config data and how can I get it out from this JSON so I can pass it to a variable.

As for grabbing the data from the config.data, I have tried for loops but they either push 56 elements of 56 numbers to the empty array or don't do nothing.

Client side:

state = {
  bank_name: '',
  account_number: ''
}

...

onSubmit = (e) => {
  e.preventDefault()

  axios.post('http://localhost:9000/api/bank', {
    bankName: this.state.bank_name,
    accNumber: this.state.account_number
   })
    .then(res => {
      console.log(res)
    }).catch(err => console.log(err))
  }

Server side:

router.post('/', (req, res) => {
    const {reqData} = req;
    res.send(reqData);
})

Console log from client side ( console.log(res) ):

{
  config: {
    url: "http://localhost:9000/api/bank",
    method: "post",
    data: '{"bankName":"some new bank","accNumber":"39276542934235"}'
  },
  data: "success",
  headers: "...",
  request: "...",
  status: 200,
  statusText: "OK",
  __proto__: Object
}
...

When I target res.config.data.bankName I get undefined.

I believe this has to do with the server response being as it is, or not parsing the data server receives in the first place, or it is due to promises.

Any input would be helpful, thanks

Answer 1

That res.config.data is string so parse it first JSON.parse(res.config.data) and then access the bankName.

Also you must be using body-parser at the express end. And so post data resides in req.body you should send that back not the whole req IMO.

Express:

router.post('/', (req, res) => {
    const reqData = req.body;
    return res.send(reqData);
});

Axios: (returned data should be in res.data)

  axios.post('http://localhost:9000/api/bank', {
    bankName: this.state.bank_name,
    accNumber: this.state.account_number
   })
    .then(res => {
      console.log(res.data);
    }).catch(err => console.log(err))
  }