JAVASCRIPT

return axios response from seperate file

import axios from 'axios';

export const onAuthenticate = payload => {
  const URL = `YOUR_URL`;
  return axios(URL, {
    method: 'POST/GET',
    headers: {
      'content-type': 'application/json', // whatever you want
    },
    data: payload,
  })
    .then(response => response.data)
    .catch(error => {
      throw error;
    });
};
in you App.js

import * as AuthenticateAPI from 'api/AuthenticationAPI';

 // in your CDM
 componentDidMount(){
  AuthenticateAPI.onAuthenticate(payload).then((res)=>{ //any payload you want to send just for example
    you can get response here in then block
 }) 
 }

return axios response from seperate file

import axios from 'axios';

export function getData(config, callback, errorcallback){
    axios.get(url, config)
    .then(res => {
      //do something
      if(callback != null){
         callback(res);
      }
    })
    .catch(err => {
      // catch error
      if(errorcallback != null){
         errorcallback(err);
      }
    })
}
In any component, use as follows

// get the location of your apicalls.js file and use to import like below
import { getData } from '../../routetothisjsfile'


//use it 
var config = { "Access-Control-Allow-Origin": "*" }
getData(config, (res) => {
    //success
},(err) => {
    //error
    alert(err);
});