/*
 * Copyright (c) 2011-2017 Contributors to the Eclipse Foundation
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
 * which is available at https://www.apache.org/licenses/LICENSE-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
 */

package io.vertx.core.http;

import io.vertx.codegen.annotations.Fluent;
import io.vertx.codegen.annotations.GenIgnore;
import io.vertx.codegen.annotations.VertxGen;
import io.vertx.core.Future;
import io.vertx.core.Handler;
import io.vertx.core.MultiMap;
import io.vertx.core.metrics.Measured;
import io.vertx.core.streams.ReadStream;

import java.util.function.Function;

/**
 * An asynchronous HTTP client.
 * <p>
 * It allows you to make requests to HTTP servers, and a single client can make requests to any server.
 * <p>
 * It also allows you to open WebSockets to servers.
 * <p>
 * The client can also pool HTTP connections.
 * <p>
 * For pooling to occur, keep-alive must be true on the {@link io.vertx.core.http.HttpClientOptions} (default is true).
 * In this case connections will be pooled and re-used if there are pending HTTP requests waiting to get a connection,
 * otherwise they will be closed.
 * <p>
 * This gives the benefits of keep alive when the client is loaded but means we don't keep connections hanging around
 * unnecessarily when there would be no benefits anyway.
 * <p>
 * The client also supports pipe-lining of requests. Pipe-lining means another request is sent on the same connection
 * before the response from the preceding one has returned. Pipe-lining is not appropriate for all requests.
 * <p>
 * To enable pipe-lining, it must be enabled on the {@link io.vertx.core.http.HttpClientOptions} (default is false).
 * <p>
 * When pipe-lining is enabled the connection will be automatically closed when all in-flight responses have returned
 * and there are no outstanding pending requests to write.
 * <p>
 * The client is designed to be reused between requests.
 *
 * @author <a href="http://tfox.org">Tim Fox</a>
 */
@VertxGen
public interface HttpClient extends Measured {

  /**
   * Create an HTTP request to send to the server with the specified options.
   *
   * @param method  the HTTP method
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, RequestOptions options);

  /**
   * Create an HTTP request to send to the server at the specified host and port.
   * @param method  the HTTP method
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, int port, String host, String requestURI);

  /**
   * Create an HTTP request to send to the server at the specified host and default port.
   * @param method  the HTTP method
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, String host, String requestURI);

  /**
   * Create an HTTP request to send to the server with the specified options, specifying a response handler to receive
   *
   * @param method  the HTTP method
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP request to send to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param method  the HTTP method
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP request to send to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param method  the HTTP method
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP request to send to the server at the default host and port.
   * @param method  the HTTP method
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, String requestURI);

  /**
   * Create an HTTP request to send to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param method  the HTTP method
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest request(HttpMethod method, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP request to send to the server using an absolute URI
   * @param method  the HTTP method
   * @param absoluteURI  the absolute URI
   * @return  an HTTP client request object
   */
  HttpClientRequest requestAbs(HttpMethod method, String absoluteURI);

  /**
   * Create an HTTP request to send to the server using an absolute URI, specifying a response handler to receive
   * the response
   * @param method  the HTTP method
   * @param absoluteURI  the absolute URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest requestAbs(HttpMethod method, String absoluteURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP GET request to send to the server with the specified options.
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest get(RequestOptions options);

  /**
   * Create an HTTP GET request to send to the server at the specified host and port.
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest get(int port, String host, String requestURI);

  /**
   * Create an HTTP GET request to send to the server at the specified host and default port.
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest get(String host, String requestURI);

  /**
   * Create an HTTP GET request to send to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest get(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP GET request to send to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest get(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP GET request to send to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest get(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP GET request to send to the server at the default host and port.
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest get(String requestURI);

  /**
   * Create an HTTP GET request to send to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest get(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP GET request to send to the server using an absolute URI
   * @param absoluteURI  the absolute URI
   * @return  an HTTP client request object
   */
  HttpClientRequest getAbs(String absoluteURI);

  /**
   * Create an HTTP GET request to send to the server using an absolute URI, specifying a response handler to receive
   * the response
   * @param absoluteURI  the absolute URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest getAbs(String absoluteURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP GET request to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient getNow(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP GET request to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient getNow(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP GET request to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient getNow(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP GET request  to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient getNow(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP POST request to send to the server with the specified options.
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest post(RequestOptions options);

  /**
   * Create an HTTP POST request to send to the server at the specified host and port.
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest post(int port, String host, String requestURI);

  /**
   * Create an HTTP POST request to send to the server at the specified host and default port.
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest post(String host, String requestURI);

  /**
   * Create an HTTP POST request to send to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest post(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP POST request to send to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest post(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP POST request to send to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest post(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP POST request to send to the server at the default host and port.
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest post(String requestURI);

  /**
   * Create an HTTP POST request to send to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest post(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP POST request to send to the server using an absolute URI
   * @param absoluteURI  the absolute URI
   * @return  an HTTP client request object
   */
  HttpClientRequest postAbs(String absoluteURI);

  /**
   * Create an HTTP POST request to send to the server using an absolute URI, specifying a response handler to receive
   * the response
   * @param absoluteURI  the absolute URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest postAbs(String absoluteURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP HEAD request to send to the server with the specified options.
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest head(RequestOptions options);

  /**
   * Create an HTTP HEAD request to send to the server at the specified host and port.
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest head(int port, String host, String requestURI);

  /**
   * Create an HTTP HEAD request to send to the server at the specified host and default port.
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest head(String host, String requestURI);

  /**
   * Create an HTTP HEAD request to send to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest head(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP HEAD request to send to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest head(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP HEAD request to send to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest head(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP HEAD request to send to the server at the default host and port.
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest head(String requestURI);

  /**
   * Create an HTTP HEAD request to send to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest head(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP HEAD request to send to the server using an absolute URI
   * @param absoluteURI  the absolute URI
   * @return  an HTTP client request object
   */
  HttpClientRequest headAbs(String absoluteURI);

  /**
   * Create an HTTP HEAD request to send to the server using an absolute URI, specifying a response handler to receive
   * the response
   * @param absoluteURI  the absolute URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest headAbs(String absoluteURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP HEAD request to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient headNow(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP HEAD request to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient headNow(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP HEAD request to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient headNow(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP HEAD request  to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient headNow(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP OPTIONS request to send to the server with the specified options.
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest options(RequestOptions options);

  /**
   * Create an HTTP OPTIONS request to send to the server at the specified host and port.
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest options(int port, String host, String requestURI);

  /**
   * Create an HTTP OPTIONS request to send to the server at the specified host and default port.
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest options(String host, String requestURI);

  /**
   * Create an HTTP OPTIONS request to send to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest options(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP OPTIONS request to send to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest options(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP OPTIONS request to send to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest options(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP OPTIONS request to send to the server at the default host and port.
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest options(String requestURI);

  /**
   * Create an HTTP OPTIONS request to send to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest options(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP OPTIONS request to send to the server using an absolute URI
   * @param absoluteURI  the absolute URI
   * @return  an HTTP client request object
   */
  HttpClientRequest optionsAbs(String absoluteURI);

  /**
   * Create an HTTP OPTIONS request to send to the server using an absolute URI, specifying a response handler to receive
   * the response
   * @param absoluteURI  the absolute URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest optionsAbs(String absoluteURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP OPTIONS request to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient optionsNow(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP OPTIONS request to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient optionsNow(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP OPTIONS request to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient optionsNow(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Sends an HTTP OPTIONS request  to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient optionsNow(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP PUT request to send to the server with the specified options.
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest put(RequestOptions options);

  /**
   * Create an HTTP PUT request to send to the server at the specified host and port.
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest put(int port, String host, String requestURI);

  /**
   * Create an HTTP PUT request to send to the server at the specified host and default port.
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest put(String host, String requestURI);

  /**
   * Create an HTTP PUT request to send to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest put(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP PUT request to send to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest put(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP PUT request to send to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest put(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP PUT request to send to the server at the default host and port.
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest put(String requestURI);

  /**
   * Create an HTTP PUT request to send to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest put(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP PUT request to send to the server using an absolute URI
   * @param absoluteURI  the absolute URI
   * @return  an HTTP client request object
   */
  HttpClientRequest putAbs(String absoluteURI);

  /**
   * Create an HTTP PUT request to send to the server using an absolute URI, specifying a response handler to receive
   * the response
   * @param absoluteURI  the absolute URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest putAbs(String absoluteURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP DELETE request to send to the server with the specified options.
   * @param options  the request options
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(RequestOptions options);

  /**
   * Create an HTTP DELETE request to send to the server at the specified host and port.
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(int port, String host, String requestURI);

  /**
   * Create an HTTP DELETE request to send to the server at the specified host and default port.
   * @param host  the host
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(String host, String requestURI);

  /**
   * Create an HTTP DELETE request to send to the server with the specified options, specifying a response handler to receive
   * the response
   * @param options  the request options
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(RequestOptions options, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP DELETE request to send to the server at the specified host and port, specifying a response handler to receive
   * the response
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(int port, String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP DELETE request to send to the server at the specified host and default port, specifying a response handler to receive
   * the response
   * @param host  the host
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(String host, String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP DELETE request to send to the server at the default host and port.
   * @param requestURI  the relative URI
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(String requestURI);

  /**
   * Create an HTTP DELETE request to send to the server at the default host and port, specifying a response handler to receive
   * the response
   * @param requestURI  the relative URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest delete(String requestURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Create an HTTP DELETE request to send to the server using an absolute URI
   * @param absoluteURI  the absolute URI
   * @return  an HTTP client request object
   */
  HttpClientRequest deleteAbs(String absoluteURI);

  /**
   * Create an HTTP DELETE request to send to the server using an absolute URI, specifying a response handler to receive
   * the response
   * @param absoluteURI  the absolute URI
   * @param responseHandler  the response handler
   * @return  an HTTP client request object
   */
  HttpClientRequest deleteAbs(String absoluteURI, Handler<HttpClientResponse> responseHandler);

  /**
   * Connect a WebSocket with the specified options
   * @param options  the request options
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket with the specified options
   * @param options  the request options
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the host and relative request URI and default port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the host and relative request URI and default port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket with the specified options, and with the specified headers
   * @param options  the request options
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, MultiMap headers, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI, and with the specified headers
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, MultiMap headers, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket with the specified options, and with the specified headers
   * @param options  the request options
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, MultiMap headers, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI, and with the specified headers
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, MultiMap headers, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the specified host,relative request UR, and default port and with the specified headers
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, MultiMap headers, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the specified host,relative request UR, and default port and with the specified headers
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, MultiMap headers, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket with the specified optionsI, with the specified headers and using
   * the specified version of WebSockets
   * @param options  the request options
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI, with the specified headers and using
   * the specified version of WebSockets
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket with the specified options, with the specified headers and using
   * the specified version of WebSockets
   * @param options  the request options
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI, with the specified headers and using
   * the specified version of WebSockets
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the specified host, relative request URI and default port with the specified headers and using
   * the specified version of WebSockets
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the specified host, relative request URI and default port with the specified headers and using
   * the specified version of WebSockets
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket with the specified options, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param options  the request options
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket with the specified absolute url, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols.
   *
   * @param url            the absolute url
   * @param headers        the headers
   * @param version        the websocket version
   * @param subProtocols   the subprotocols to use
   * @param wsConnect      handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocketAbs(String url, MultiMap headers, WebsocketVersion version, String subProtocols, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket with the specified options, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param options  the request options
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(RequestOptions options, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the specified port, host and relative request URI, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(int port, String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket to the specified host, relative request URI and default port, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket to the specified host, relative request URI and default port, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String host, String requestURI, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket at the relative request URI using the default host and port
   * @param requestURI  the relative URI
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket at the relative request URI using the default host and port
   * @param requestURI  the relative URI
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket at the relative request URI using the default host and port and the specified headers
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, MultiMap headers, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket at the relative request URI using the default host and port and the specified headers
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, MultiMap headers, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);

  /**
   * Connect a WebSocket at the relative request URI using the default host and port, the specified headers and the
   * specified version of WebSockets
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket at the relative request URI using the default host and port, the specified headers and the
   * specified version of WebSockets
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, MultiMap headers, WebsocketVersion version,
                       Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);


  /**
   * Connect a WebSocket at the relative request URI using the default host and port, the specified headers, the
   * specified version of WebSockets and the specified sub protocols
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols
   * @param wsConnect  handler that will be called with the websocket when connected
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect);

  /**
   * Connect a WebSocket at the relative request URI using the default host and port, the specified headers, the
   * specified version of WebSockets and the specified sub protocols
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols
   * @param wsConnect  handler that will be called with the websocket when connected
   * @param failureHandler handler that will be called if websocket connection fails
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient websocket(String requestURI, MultiMap headers, WebsocketVersion version,
                       String subProtocols, Handler<WebSocket> wsConnect, Handler<Throwable> failureHandler);


  /**
   * Create a WebSocket stream with the specified options
   * @param options  the request options
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(RequestOptions options);

  /**
   * Create a WebSocket stream to the specified port, host and relative request URI
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(int port, String host, String requestURI);

  /**
   * Create a WebSocket stream to the specified host, relative request URI and default port
   * @param host  the host
   * @param requestURI  the relative URI
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String host, String requestURI);

  /**
   * Create a WebSocket stream with the specified options, and with the specified headers
   * @param options  the request options
   * @param headers  the headers
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(RequestOptions options, MultiMap headers);

  /**
   * Create a WebSocket stream to the specified port, host and relative request URI, and with the specified headers
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(int port, String host, String requestURI, MultiMap headers);

  /**
   * Create a WebSocket stream to the specified host, relative request URI and default port and with the specified headers
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String host, String requestURI, MultiMap headers);

  /**
   * Create a WebSocket stream with the specified options, with the specified headers and using
   * the specified version of WebSockets
   * @param options  the request options
   * @param headers  the headers
   * @param version  the websocket version
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(RequestOptions options, MultiMap headers, WebsocketVersion version);

  /**
   * Create a WebSocket stream to the specified port, host and relative request URI, with the specified headers and using
   * the specified version of WebSockets
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(int port, String host, String requestURI, MultiMap headers, WebsocketVersion version);

  /**
   * Create a WebSocket stream with the specified options and with the specified headers and using
   * the specified version of WebSockets
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String host, String requestURI, MultiMap headers, WebsocketVersion version);

  /**
   * Create a WebSocket stream with the specified absolute url, the specified headers, using the specified version of WebSockets,
   * and the specified websocket sub protocols.
   *
   * @param url          the absolute url
   * @param headers      the headers
   * @param version      the websocket version
   * @param subProtocols the subprotocols to use
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStreamAbs(String url, MultiMap headers, WebsocketVersion version, String subProtocols);

  /**
   * Create a WebSocket stream to the specified port, host and relative request URI, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param options  the request options
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(RequestOptions options, MultiMap headers, WebsocketVersion version,
                                  String subProtocols);

  /**
   * Create a WebSocket stream to the specified port, host and relative request URI, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param port  the port
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(int port, String host, String requestURI, MultiMap headers, WebsocketVersion version,
                                  String subProtocols);

  /**
   * Create a WebSocket stream to the specified host, relative request URI and default port, with the specified headers, using
   * the specified version of WebSockets, and the specified websocket sub protocols
   * @param host  the host
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols to use
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String host, String requestURI, MultiMap headers, WebsocketVersion version,
                                  String subProtocols);

  /**
   * Create a WebSocket stream at the relative request URI using the default host and port and the specified headers
   * @param requestURI  the relative URI
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String requestURI);

  /**
   * Create a WebSocket stream at the relative request URI using the default host and port and the specified headers
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String requestURI, MultiMap headers);

  /**
   * Create a WebSocket stream at the relative request URI using the default host and port, the specified headers and the
   * specified version of WebSockets
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String requestURI, MultiMap headers, WebsocketVersion version);

  /**
   * Create a WebSocket stream at the relative request URI using the default host and port, the specified headers, the
   * specified version of WebSockets and the specified sub protocols
   * @param requestURI  the relative URI
   * @param headers  the headers
   * @param version  the websocket version
   * @param subProtocols  the subprotocols
   * @return a stream emitting a WebSocket event when the client connection has been upgraded to a websocket
   */
  ReadStream<WebSocket> websocketStream(String requestURI, MultiMap headers, WebsocketVersion version,
                                  String subProtocols);

  /**
   * Set a redirect handler for the http client.
   * <p>
   * The redirect handler is called when a {@code 3xx} response is received and the request is configured to
   * follow redirects with {@link HttpClientRequest#setFollowRedirects(boolean)}.
   * <p>
   * The redirect handler is passed the {@link HttpClientResponse}, it can return an {@link HttpClientRequest} or {@code null}.
   * <ul>
   *   <li>when null is returned, the original response is processed by the original request response handler</li>
   *   <li>when a new {@code Future<HttpClientRequest>} is returned, the client will send this new request</li>
   * </ul>
   * The handler must return a {@code Future<HttpClientRequest>} unsent so the client can further configure it and send it.
   *
   * @param handler the new redirect handler
   * @return a reference to this, so the API can be used fluently
   */
  @Fluent
  HttpClient redirectHandler(Function<HttpClientResponse, Future<HttpClientRequest>> handler);

  /**
   * @return the current redirect handler.
   */
  @GenIgnore
  Function<HttpClientResponse, Future<HttpClientRequest>> redirectHandler();

  /**
   * Close the client. Closing will close down any pooled connections.
   * Clients should always be closed after use.
   */
  void close();
}
