title: User authentication when consuming a REST webservice with ServiceStack
body: <p>The <a href="http://www.servicestack.net">ServiceStack</a> docs are full of examples on how to use <em>server side</em> implementation of authentication of a user. But how does one set the user credentials on the client side?</p>
  
  <p>I use ServiceStack to consume a <code>JSON REST</code> service like this:</p>
  
  <pre><code>var restClient = new JsonServiceClient (baseUri);
  var response = restClient.Get&lt;MyResponse&gt; ("/some/service");
  </code></pre>
  
  <p>How can I add any form of authentication to the request? The webservice I want to consume uses <code>OAuth 1.0</code>, but I am interested in adding custom authentication, too.</p>
  
  <p>In my code, I have previously performed OAuth token exchange successfully, so I already own a valid access token and need to sign every REST request now using this access token and its <code>token_secret</code>.</p>