Decouple channel connector from pool and connection queue

src/main/java/io/vertx/core/http/impl/ClientConnection.java

@@ -66,6 +66,7 @@ class ClientConnection extends Http1xConnectionBase implements HttpClientConnect
 
   private static final Logger log = LoggerFactory.getLogger(ClientConnection.class);
 
+  private final ClientConnectionListener<HttpClientConnection> listener;
   private final HttpClientImpl client;
   private final boolean ssl;
   private final String host;
@@ -79,9 +80,6 @@ class ClientConnection extends Http1xConnectionBase implements HttpClientConnect
   private final HttpClientMetrics metrics;
   private final HttpVersion version;
 
-  private Handler<Void> concurrencyUpdateHandler;
-  private Handler<Void> evictionHandler;
-
   private WebSocketClientHandshaker handshaker;
   private HttpClientRequestImpl currentRequest;
   private HttpClientResponseImpl currentResponse;
@@ -92,9 +90,18 @@ class ClientConnection extends Http1xConnectionBase implements HttpClientConnect
   private boolean paused;
   private Buffer pausedChunk;
 
-  ClientConnection(HttpVersion version, HttpClientImpl client, Object endpointMetric, ChannelHandlerContext channel, boolean ssl, String host,
-                   int port, ContextImpl context, HttpClientMetrics metrics) {
+  ClientConnection(ClientConnectionListener<HttpClientConnection> listener,
+                   HttpVersion version,
+                   HttpClientImpl client,
+                   Object endpointMetric,
+                   ChannelHandlerContext channel,
+                   boolean ssl,
+                   String host,
+                   int port,
+                   ContextImpl context,
+                   HttpClientMetrics metrics) {
     super(client.getVertx(), channel, context);
+    this.listener = listener;
     this.client = client;
     this.ssl = ssl;
     this.host = host;
@@ -112,18 +119,6 @@ public Channel channel() {
     return chctx.channel();
   }
 
-  @Override
-  public HttpClientConnection concurrencyUpdateHandler(Handler<Void> handler) {
-    concurrencyUpdateHandler = handler;
-    return this;
-  }
-
-  @Override
-  public HttpClientConnection evictionHandler(Handler<Void> handler) {
-    evictionHandler = handler;
-    return this;
-  }
-
   public HttpClientMetrics metrics() {
     return metrics;
   }
@@ -464,7 +459,7 @@ public void reset(long code) {
   private void requestEnded() {
     context.runOnContext(v -> {
       if (pipelining && requests.size() < pipeliningLimit) {
-        concurrencyUpdateHandler.handle(null);
+        listener.onRecycle(this);
       }
     });
   }
@@ -475,7 +470,7 @@ private void responseEnded() {
     } else {
       context.runOnContext(v -> {
         if (currentRequest == null) {
-          concurrencyUpdateHandler.handle(null);
+          listener.onRecycle(this);
         }
       });
     }
@@ -634,7 +629,7 @@ protected void handleMessage(NetSocketImpl connection, ContextImpl context, Chan
         ByteBuf buf = (ByteBuf) msg;
         connection.handleMessageReceived(buf);
       }
-    }.removeHandler(sock -> evictionHandler.handle(null)));
+    }.removeHandler(sock -> listener.onClose(this, chctx.channel())));
     return socket;
   }
 
@@ -645,9 +640,7 @@ public HttpClientConnection connection() {
 
   @Override
   public HttpVersion version() {
-    // Used to determine the http version in the HttpClientRequest#sendHead handler , for HTTP/1.1 it will
-    // not yet know but it will for HTTP/2
-    return null;
+    return version;
   }
 
   @Override

src/main/java/io/vertx/core/http/impl/ClientConnectionListener.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2011-2013 The original author or authors
+ * ------------------------------------------------------
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * and Apache License v2.0 which accompanies this distribution.
+ *
+ *     The Eclipse Public License is available at
+ *     http://www.eclipse.org/legal/epl-v10.html
+ *
+ *     The Apache License v2.0 is available at
+ *     http://www.opensource.org/licenses/apache2.0.php
+ *
+ * You may elect to redistribute this code under either of these licenses.
+ */
+package io.vertx.core.http.impl;
+
+import io.netty.channel.Channel;
+
+public interface ClientConnectionListener<C> {
+
+  void onRecycle(C conn);
+
+  void onClose(C conn, Channel channel);
+
+}

src/main/java/io/vertx/core/http/impl/ClientHandler.java

@@ -25,7 +25,7 @@
 import io.netty.handler.codec.http.LastHttpContent;
 import io.netty.handler.codec.http.websocketx.PongWebSocketFrame;
 import io.vertx.core.buffer.Buffer;
-import io.vertx.core.http.impl.ws.WebSocketFrameImpl;
+import io.vertx.core.http.HttpVersion;
 import io.vertx.core.http.impl.ws.WebSocketFrameInternal;
 import io.vertx.core.impl.ContextImpl;
 import io.vertx.core.spi.metrics.HttpClientMetrics;
@@ -37,34 +37,43 @@ class ClientHandler extends VertxHttpHandler<ClientConnection> {
   private boolean closeFrameSent;
   private ContextImpl context;
   private ChannelHandlerContext chctx;
-  private Http1xPool pool;
-  private HttpClientImpl client;
-  private Object endpointMetric;
-  private HttpClientMetrics metrics;
+  private final HttpVersion version;
+  private final String host;
+  private final int port;
+  private final boolean ssl;
+  private final HttpClientImpl client;
+  private final HttpClientMetrics metrics;
+  private final ClientConnectionListener<HttpClientConnection> listener;
+  private final Object endpointMetric;
 
-  public ClientHandler(ContextImpl context,
-                       Http1xPool pool,
+  public ClientHandler(ClientConnectionListener<HttpClientConnection> listener,
+                       ContextImpl context,
+                       HttpVersion version,
+                       String host,
+                       int port,
+                       boolean ssl,
                        HttpClientImpl client,
                        Object endpointMetric,
                        HttpClientMetrics metrics) {
     this.context = context;
-    this.pool = pool;
+    this.version = version;
     this.client = client;
+    this.host = host;
+    this.port = port;
+    this.ssl = ssl;
     this.endpointMetric = endpointMetric;
     this.metrics = metrics;
+    this.listener = listener;
   }
 
   @Override
   public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
     chctx = ctx;
-    ClientConnection conn = new ClientConnection(pool.version(), client, endpointMetric, ctx,
-      pool.ssl(), pool.host(), pool.port(), context, metrics);
+    ClientConnection conn = new ClientConnection(listener, version, client, endpointMetric, ctx, ssl, host, port, context, metrics);
     if (metrics != null) {
-      context.executeFromIO(() -> {
-        Object metric = metrics.connected(conn.remoteAddress(), conn.remoteName());
-        conn.metric(metric);
-        metrics.endpointConnected(endpointMetric, metric);
-      });
+      Object metric = metrics.connected(conn.remoteAddress(), conn.remoteName());
+      conn.metric(metric);
+      metrics.endpointConnected(endpointMetric, metric);
     }
     setConnection(conn);
   }
@@ -73,6 +82,14 @@ public ChannelHandlerContext context() {
     return chctx;
   }
 
+  @Override
+  public void channelInactive(ChannelHandlerContext chctx) throws Exception {
+    if (metrics != null) {
+      metrics.endpointDisconnected(endpointMetric, getConnection().metric());
+    }
+    super.channelInactive(chctx);
+  }
+
   @Override
   protected void handleMessage(ClientConnection conn, ContextImpl context, ChannelHandlerContext chctx, Object msg) throws Exception {
     if (msg instanceof HttpObject) {