title: How to get authentication imperatively in reactive Spring?
body: <p>I am using Javers and need to provide the author of a commit. In order to do this, I create this class</p>
  <pre><code>  private class SimpleAuthorProvider : AuthorProvider {
  
      override fun provide(): String {
          return &quot;the_author&quot;
      }
  }
  </code></pre>
  <p>However instead of hard coding the string, I would like to use the user who has sent the request. I am using a <code>ReactiveAuthenticationManager</code> to set the authentication. This means I need to access it using <code>ReactiveSecurityContextHolder.getContext()</code> which returns a Mono. As I need to essentially return a string from this, I am not sure how to access it?</p>
  <p>I have tried to even do a hack or two e.g. <code>block()</code> or <code>toFuture().get()</code> but these both do not work.</p>
  <p>Are there any other suggestions?</p>