Preemptive authentication

[Joakim-T]

Struggling authenticating with a REST API that requires preemptive authentication.
How do i configure this in Thunder Client?

[rangav]

Hi @Joakim-T

Can you share more info like code samples or screenshots

[Joakim-T]

Hello!
Basic authentication (Dummy user/password below) and i get 401 Unauthorized back.
A colleague uses SOAP UI and the same request works when he enables "Authenticate pre-emptively".
Is this somehing Thunder Client cannot do?

var client = new HttpClient();
var request = new HttpRequestMessage();
request.RequestUri = new Uri("https://test/api/query/org?companyID=AV&select=avd");
request.Method = HttpMethod.Get;

request.Headers.Add("Accept", "application/json");
request.Headers.Add("User-Agent", "Thunder Client");
request.Headers.Add("Authorization", "Basic dXNlcm5hbWU6cGFzc3dvcmQ=");

var response = await client.SendAsync(request);
var result = await response.Content.ReadAsStringAsync();
Console.WriteLine(result);

[rangav]

The code sample you shared looks like a simple GET request with base auth. I am not sure what SOAP UI is doing additionally.

Will do some research and get back to you.

[rangav]

preemptive authentication?

This means that the browser is not authenticated with the initial request, but rather gets an 'unauthorized' response for the server, which triggers the authentication request to be sent after. If the server does not respond with a 400 error, the authentication is not sent after and the test will error.

https://community.smartbear.com/t5/AlertSite-Questions/Preemptive-Authentication-and-SoapUI-Tests-versus-Single-URL/m-p/157896/highlight/true#M355

[gambrjl]

Has anyone found a work around for this? from the link above the API I'm calling is giving 403 Unauthorized and the auth credentials are not being sent b/c it's not 400 if I'm understanding. SOAP works with the Authenticate pre-emptively flag