title: DocuSign API - How to get callback response after user authentication?
body: <p>I'm trying to implement the <a href="https://developers.docusign.com/esign-rest-api/guides/authentication/oauth2-implicit" rel="nofollow noreferrer">Implicit Grant REST API of DocuSign</a>. I'm confused as to what needs to happen right after the user logs in. This is a stand-alone native Windows desktop application, not a web service or page.</p>
  <p>I got as far as to open an embedded browser window, navigating to the correct URI for login, and the user is able to successfully login. I further have an HTTP server running in this application as well which is to receive the callback. In fact, the callback does work, I do get an incoming HTTP GET command. However, there is nothing usable in this callback response. No special headers, parameters, body, nothing.</p>
  <p>Before I tried the Implicit Grant API, I first tried the JWT Grant method, before realizing it wasn't the right approach. But my point is, at least I had a <code>code</code> parameter in the callback command. But after shifting over to use the Implicit Grant method, this response is empty.</p>
  <p>According to the documentation:</p>
  <blockquote>
  <p>After consent has been granted, the Authentication Service verifies that the client application is valid and has access to the requested scope. If so, it redirects the access token to the provided callback URI in a hash fragment.</p>
  <p>The response contains the following hash fragment parameters:</p>
  <p>.......</p>
  </blockquote>
  <p>It even shows an example response:</p>
  <pre><code>http://localhost/#access_token=eyJ0eXAi.....9LyiFrUqvdw&amp;expires_in=28800&amp;token_type=bearer&amp;state=a39fh23hnf23
  </code></pre>
  <p>But, as mentioned, the callback response I receive has nothing of notable value. It's essentially just empty.</p>
  <p>What am I missing here? What's the correct approach to complete the authentication process and proceed to actually using the API?</p>
  <p>NOTE: I'm using Delphi, so none of the examples provided by DocuSign are compatible.</p>