Ionic http requests with authorization headers - angularjs

Question

I am sending a get request to the server and it requires a JWT token to authenticate. However Ionic insists on doing a pref-etch request without one and crashing. (Also is there any way to capture non 200 responses? the server gives a lot of those (e.g. 403 {message: Account Invalid}))
Code
auth.ts
import { Headers, RequestOptions } from '#angular/http'
import 'rxjs/add/operator/toPromise';
...
export const getToken = function(http){
return new Promise((resolve, reject) => {
let headers = new Headers();
headers.append('Content-Type', 'application/x-www-form-urlencoded');
headers.append('Authorization', 'JWT eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6IjU4Yzg1MmI1YmQ1NjE1MGJkMDAxZWEzNyIsImlhdCI6MTQ4OTY3ODE0NywiZXhwIjoxNDg5NjgxNzQ3fQ.zUWvBnHXbgW20bE65tKe3icFWYW6WKIK6STAe0w7wC4');
let options = new RequestOptions({headers: headers});
http.get('//localhost:3000/auth/users', {headers: options})
.toPromise()
.then(res => resolve(res))
.catch(err => console.log(err));
});
}
Chrome console:
Response for preflight has invalid HTTP status code 401
Server sees: (I logged out the request and there are no headers or body)
OPTIONS /auth/users 401 25.613 ms - -

Answer 1

import { Component } from '#angular/core';
import { NavController } from 'ionic-angular';
import { Toast, Device } from 'ionic-native';
import { Http, Headers } from '#angular/http';
let headers = new Headers();
headers.append('Token', this.Token);
headers.append('id', this.ID);
this.http.get(this.apiUrl + this.yourUrl, { headers: headers })
.map(res => res.json())
.subscribe(
data => {
console.log(data);
if (data.code == 200) { // this is where u r handling 200 responses
if (data.result.length > 0) {
for (let i = 0; i < data.result.length; i++) {
var userData = {
username: data.result[i].username,
firstName: data.result[i].firstName,
lastName: data.result[i].lastName,
}
console.log(JSON.stringify(userData));
this.Results.push(userData);
}
}
}
else { // here non 200 responses
console.log(data.message);
}
this.user= this.Results;
console.log(this.user);
},
err => {
console.log("ERROR!: ", err);
});
this way u will be able to handle all responses from backend
I hope this works for you

Answer 2

To anyone else having this issue. devanshsadhotra's answer is great but here is the way I solved this issue:
ionic.config.json (add all the relevant routes here)
"proxies": [
{
"path": "/api",
"proxyUrl": "http://localhost:3000/api"
},
{
"path": "/auth",
"proxyUrl": "http://localhost:3000/auth"
}
]
Your networking file (auth.js in this case)
import { Headers } from '#angular/http' //Headers need to be in this object type
import 'rxjs/add/operator/toPromise'; //turns observable into promise
export const getToken = function(http){ //passing in the Http handler to the function for no good reason. but it works
return new Promise((resolve, reject) => { //return a promise to the calling function so it can handle the response
let headers = new Headers();
headers.append('Content-Type', 'application/x-www-form-urlencoded');
headers.append('Authorization', 'JWT eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6IjU4Yzg1MmI1YmQ1NjE1MGJkMDAxZWEzNyIsImlhdCI6MTQ4OTY4MjY2MywiZXhwIjoxNDg5Njg2MjYzfQ.tW8nT5xYKTqW9wWG3thdwf7OX8g3DrdccM4aYkOmp8w');
http.get('/auth/users', {headers: headers}) //for post, put and delete put the body before the headers
.toPromise() //SANITY!!!
.then(res => resolve(res)) //Things went well....
.catch(err => console.log(err)); //Things did not...
});
}