title: Route akka-http request through a proxy
body: <p>I am rewriting some application layer code in scala from using scalaj to akka-http
  in order to reduce the number of third party dependencies in the project (we already use akka for other things in the same project.) The code simply wraps common types of request to an underlying general request provided by the library</p>
  
  <p>Mostly it has been fine, but I am stuck on the problem of optionally adding a proxy to a request.</p>
  
  <p>Requests should either be direct to the destination or via a proxy, determined by a parameter at runtime.</p>
  
  <p>In my scalaj implementation, I have the following helper class and methods</p>
  
  <pre><code>object HttpUtils {
    private def request(
                 host: Host,
                 method: HttpMethod,
                 params: Map[String, String],
                 postData: Option[String],
                 timeout: Duration,
                 headers: Seq[(String, String)],
                 proxy: Option[ProxyConfig]
               ): HttpResponse[String] = {
      // most general request builder. Other methods in the object fill in parameters and wrap this in a Future
      val baseRequest = Http(host.url)
      val proxiedRequest = addProxy(proxy, baseRequest)
      val fullRequest = addPostData(postData)(proxiedRequest)
        .method(method.toString)
        .params(params)
        .headers(headers)
        .option(HttpOptions.connTimeout(timeout.toMillis.toInt))
        .option(HttpOptions.readTimeout(timeout.toMillis.toInt))
      fullRequest.asString  // scalaj for send off request and block until response
    }
  
        // Other methods ...
  
     private def addProxy(proxy: Option[ProxyConfig], request: HttpRequest): HttpRequest =
       proxy.fold(request)((p: ProxyConfig) =&gt; request.proxy(p.host, p.port))
  }
  
  case class ProxyConfig(host: String, port: Int)
  </code></pre>
  
  <p>Is there a way to build a similar construct with akka-http?</p>