title: How to call asynchronously WCF Service method with WebInvokeAttribute?
body: <p>I have WCF Service with this one method. That method has WebInvoke Attribute. How can I call it asynchronously?</p>
  
  <pre class="lang-cs prettyprint-override"><code>[WebInvoke(UriTemplate = "*", Method = "*")]
  public Message HandleRequest()
  {
      var webContext = WebOperationContext.Current;
      var webClient = new WebClient();
  
      return webContext.CreateStreamResponse(webClient.OpenRead("http://site.com"), "text/html");
  }
  </code></pre>