Accessing OAuth Servers using Flurl

If you have Flurl installed, and you need your client to authenticate against an OAuth2 server, like Identity Server, you can use their client library, which does everything for you (without Flurl), or you can do it yourself.

below is my DIY version.

private const string SECURITY_HOST = "your security host.";
private const string API_HOST = "your test api host";

string.WriteTitle() & string.WriteContent() are extension methods I slapped together to dump the information to the console screen, formatted.

"Ready to start with Flurl...".WriteTitle();
Console.ReadLine();
 
// discover endpoints from metadata
var discoraw = await SECURITY_HOST.AppendPathSegments(".well-known","openid-configuration").GetAsync();
var contentraw = await discoraw.Content.ReadAsStringAsync();
$"Discovery: {discoraw}".WriteContent(title: "Discovery");
$"Disco Content: {contentraw}".WriteContent(title: "Discovery");
var disco = JsonConvert.DeserializeObject(contentraw);
 
// request token
var authorizationAddr = (string)disco.token_endpoint;
 
var authorizationObj = await authorizationAddr.PostUrlEncodedAsync(new { client_id = "client", client_secret = "secret", grant_type = "client_credentials", scope="api1" });
var authorizationString = await authorizationObj.Content.ReadAsStringAsync();
$"Token Response: {authorizationString}".WriteContent(title:"Authorization");
 
var tokenContainer = JsonConvert.DeserializeObject(authorizationString);
  
var apiCall = await $"{API_HOST}/identity".WithOAuthBearerToken((string)tokenContainer.access_token).GetAsync();
 
var apiCallResponse = await apiCall.Content.ReadAsStringAsync();
 
$"Claims from API: {apiCallResponse}".WriteContent(title:"API Call");
 
"Press any key to continue...".WriteTitle();
Console.ReadLine();

Enjoy!