Use canUpgradeToWebsocket method of Vert.x core (#63)

Fixes #62

Follows-up on eclipse-vertx/vert.x#5098

Signed-off-by: Thomas Segismont <tsegismont@gmail.com>

Author: tsegismont

src/main/java/io/vertx/httpproxy/impl/ReverseProxy.java

@@ -12,33 +12,14 @@
 
 import io.vertx.core.Future;
 import io.vertx.core.Promise;
-import io.vertx.core.http.HttpClient;
-import io.vertx.core.http.HttpClientRequest;
-import io.vertx.core.http.HttpClientResponse;
-import io.vertx.core.http.HttpHeaders;
-import io.vertx.core.http.HttpMethod;
-import io.vertx.core.http.HttpServerRequest;
-import io.vertx.core.http.HttpServerResponse;
-import io.vertx.core.http.HttpVersion;
-import io.vertx.core.http.RequestOptions;
+import io.vertx.core.http.*;
 import io.vertx.core.net.NetSocket;
-import io.vertx.core.net.SocketAddress;
-import io.vertx.httpproxy.HttpProxy;
-import io.vertx.httpproxy.ProxyContext;
-import io.vertx.httpproxy.ProxyInterceptor;
-import io.vertx.httpproxy.ProxyOptions;
-import io.vertx.httpproxy.ProxyRequest;
-import io.vertx.httpproxy.ProxyResponse;
+import io.vertx.httpproxy.*;
 import io.vertx.httpproxy.cache.CacheOptions;
 import io.vertx.httpproxy.spi.cache.Cache;
 
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.ListIterator;
-import java.util.Map;
+import java.util.*;
 import java.util.function.BiFunction;
-import java.util.function.Function;
 
 public class ReverseProxy implements HttpProxy {
 
@@ -82,10 +63,7 @@ public void handle(HttpServerRequest request) {
     }
 
     // WebSocket upgrade tunneling
-    if (supportWebSocket &&
-        request.version() == HttpVersion.HTTP_1_1 &&
-        request.method() == HttpMethod.GET &&
-        request.headers().contains(HttpHeaders.CONNECTION, HttpHeaders.UPGRADE, true)) {
+    if (supportWebSocket && io.vertx.core.http.impl.HttpUtils.canUpgradeToWebSocket(request)) {
       handleWebSocketUpgrade(proxyRequest);
       return;
     }