How to get jwt token from NodeJs to .NET app? - node.js

Question

What is the best way to get a jwt token from a running NodeJS server, in a C# .NET Windows app?
in .NET I use HttpClient to connect to an oauth2 server (and that succeeds), but how to get the very jwt token?
In NodeJS:
const express = require('express')
const https = require('https');
const axios = require('axios');
var url = require('url');
const app = express()
const port = 3000
const agent = new https.Agent({ rejectUnauthorized: false });
async function get_token() {
try {
let url = "https://oauthservername/token.oauth2";
let formfields = "client_id=cid&grant_type=password&validator_id=ourAuthNG&client_secret=secretstring&username=billy&password=xxxxxxxxx";
let response = await axios.post(url, formfields, { httpsAgent: agent });
console.log(response.data);
} catch (error) {
console.log(error);
}
}
app.get('/token', (req, res) => {
get_token();
res.send('Eureka!');
})
app.listen(port, () => {
console.log(`Example app listening at http://localhost:${port}`)
})
This is working. I am getting the "Eureka!", in Postman as well as in my .NET HttpClient call
In my console I am getting (x-ing original info...), (output from console.log(response.data);)
{
access_token: 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',
refresh_token: 'xxxxxxxxxxxxxxxxx',
token_type: 'Bearer',
expires_in: 28799
}
So, in my C# code I do this (also getting "Eureka!", I see it in the responseBody):
private async void cmdConnectServer_Click(object sender, EventArgs e)
{
//client is HttpClient
client.BaseAddress = new Uri("http://localhost:3000/");
HttpResponseMessage response = await client.GetAsync("http://localhost:3000/token");
response.EnsureSuccessStatusCode();
string responseBody = await response.Content.ReadAsStringAsync();
}
But how to get the very token?

Answer 1

In NodeJS you never send the token result in the api response, modify it like this :
async function get_token() {
try {
let url = "https://oauthservername/token.oauth2";
let formfields = "client_id=cid&grant_type=password&validator_id=ourAuthNG&client_secret=secretstring&username=billy&password=xxxxxxxxx";
let response = await axios.post(url, formfields, { httpsAgent: agent });
console.log(response.data);
//Return the oauth2 result
return response.data;
} catch (error) {
console.log(error);
}
}
app.get('/token', (req, res) => {
//sending 'Eureka!' is pointless, instead send the token result
res.send(get_token());
})
In c#
using System;
using System.Runtime.Serialization;
using System.Text.Json;
... ...
//Class for response deserialization
[Serializable]
public class TokenResult
{
[DataMember]
public string access_token { get; set; }
[DataMember]
public string refresh_token { get; set; }
[DataMember]
public string token_type { get; set; }
[DataMember]
public long expires_in { get; set; }
}
private async void cmdConnectServer_Click(object sender, EventArgs e)
{
//client is HttpClient
client.BaseAddress = new Uri("http://localhost:3000/");
HttpResponseMessage response = await client.GetAsync("http://localhost:3000/token");
response.EnsureSuccessStatusCode();
string responseBody = await response.Content.ReadAsStringAsync();
// Deserialize the token response and get access_token property
string token = JsonSerializer.Deserialize<TokenResult>(responseBody ).access_token;
}
Or just don't use node js and do everything in c#
using System;
using System.Runtime.Serialization;
using System.Text.Json;
... ...
//Class for response deserialization
[Serializable]
public class TokenResult
{
[DataMember]
public string access_token { get; set; }
[DataMember]
public string refresh_token { get; set; }
[DataMember]
public string token_type { get; set; }
[DataMember]
public long expires_in { get; set; }
}
public string get_token()
{
HttpClientHandler OpenBarHandler = new HttpClientHandler { ServerCertificateCustomValidationCallback = HttpClientHandler.DangerousAcceptAnyServerCertificateValidator };
HttpClient _httpClient = new HttpClient(OpenBarHandler);
_httpClient.BaseAddress = new Uri("https://oauthservername/token.oauth2");
HttpRequestMessage mess = new HttpRequestMessage();
mess.Method = HttpMethod.Post;
mess.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
Dictionary<string, string> _parameters = new Dictionary<String, String>();
_parameters.Add("grant_type", "password");
_parameters.Add("username", "billy");
_parameters.Add("password", "xxxxxxxxx");
_parameters.Add("client_id", "cid");
_parameters.Add("client_secret", "secretstring");
_parameters.Add("validator_id", "ourAuthNG");
FormUrlEncodedContent encodedContent = new FormUrlEncodedContent(_parameters);
encodedContent.Headers.ContentType = new MediaTypeHeaderValue("application/x-www-form-urlencoded");
mess.Content = encodedContent;
HttpResponseMessage response = _httpClient.SendAsync(mess).Result;
if (response.IsSuccessStatusCode)
{
string strResp = response.Content.ReadAsStringAsync().Result;
return JsonSerializer.Deserialize<TokenResult>(strResp).access_token;
}
else
throw new Exception("Token retrieval failed");
}