/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.synapse.transport.nhttp;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.conn.routing.HttpRoute;
import org.apache.http.nio.NHttpClientConnection;
import org.apache.http.protocol.ExecutionContext;
import org.apache.http.protocol.HttpContext;
import org.apache.synapse.transport.http.conn.SynapseHTTPRequestFactory;
public class ConnectionPool {
private static final Log log = LogFactory.getLog(ConnectionPool.class);
/** Schema name foe SSL connections */
private final String SSL_SCHEMA_NAME = "https";
/** A map of available connections for reuse. The key selects the host+port of the
* connection and the value contains a List of available connections to destination
*/
private final Map<HttpRoute, List<NHttpClientConnection>> connMap;
public ConnectionPool() {
super();
this.connMap = Collections.synchronizedMap(new HashMap<HttpRoute, List<NHttpClientConnection>>());
}
public NHttpClientConnection getConnection(HttpRoute route) {
List<NHttpClientConnection> connections = (List<NHttpClientConnection>) connMap.get(route);
if (connections == null || connections.isEmpty()) {
if (log.isDebugEnabled()) {
log.debug("No connections available for reuse");
}
return null;
} else {
NHttpClientConnection conn = null;
synchronized (connections) {
while (!connections.isEmpty()) {
conn = (NHttpClientConnection) connections.remove(0);
if (conn.isOpen() && !conn.isStale()) {
if (log.isDebugEnabled()) {
log.debug("A connection : " + route +
" is available in the pool, and will be reused");
}
conn.requestInput(); // Make sure keep alives work properly when reused with throttling
return conn;
} else {
if (log.isDebugEnabled()) {
log.debug("closing stale connection : " + route);
}
try {
conn.close();
} catch (IOException ignore) {
}
}
}
}
return null;
}
}
public void release(NHttpClientConnection conn) {
HttpContext ctx = conn.getContext();
Axis2HttpRequest axis2Req =
(Axis2HttpRequest) ctx.getAttribute(ClientHandler.AXIS2_HTTP_REQUEST);
HttpRoute route = axis2Req.getRoute();
List<NHttpClientConnection> connections = null;
synchronized(connMap) {
// use double locking to make sure
connections = (List<NHttpClientConnection>) connMap.get(route);
if (connections == null) {
connections = Collections.synchronizedList(new LinkedList<NHttpClientConnection>());
connMap.put(route, connections);
}
}
cleanConnectionReferences(conn);
connections.add(conn);
if (log.isDebugEnabled()) {
log.debug("Released a connection : " + route +
" to the connection pool of current size : " + connections.size());
}
}
private static void cleanConnectionReferences(NHttpClientConnection conn) {
HttpContext ctx = conn.getContext();
Axis2HttpRequest axis2Req =
(Axis2HttpRequest) ctx.getAttribute(ClientHandler.AXIS2_HTTP_REQUEST);
axis2Req.clear(); // this is linked via the selection key attachment and will free itself
// on timeout of the keep alive connection. Till then minimize the
// memory usage to a few bytes
ctx.removeAttribute(ClientHandler.ATTACHMENT_KEY);
ctx.removeAttribute(ClientHandler.TUNNEL_HANDLER);
ctx.removeAttribute(ClientHandler.AXIS2_HTTP_REQUEST);
ctx.removeAttribute(ClientHandler.OUTGOING_MESSAGE_CONTEXT);
ctx.removeAttribute(ClientHandler.REQUEST_SOURCE_BUFFER);
ctx.removeAttribute(ClientHandler.RESPONSE_SINK_BUFFER);
ctx.removeAttribute(ExecutionContext.HTTP_REQUEST);
ctx.removeAttribute(ExecutionContext.HTTP_RESPONSE);
ctx.removeAttribute(SynapseHTTPRequestFactory.ENDPOINT_URL);
conn.resetOutput();
}
public void forget(NHttpClientConnection conn) {
HttpContext ctx = conn.getContext();
Axis2HttpRequest axis2Req =
(Axis2HttpRequest) ctx.getAttribute(ClientHandler.AXIS2_HTTP_REQUEST);
if (axis2Req != null) {
HttpRoute route = axis2Req.getRoute();
List<NHttpClientConnection> connections = (List<NHttpClientConnection>) connMap.get(route);
if (connections != null) {
synchronized(connections) {
connections.remove(conn);
}
}
}
}
/**
* Returns SSL Connections List for the given list host:port combinations
*
* @param hostList String List in Host:Port format
* @return List of NHttpClientConnection
*/
public List<NHttpClientConnection> getSslConnectionsList(Set<String> hostList) {
List<NHttpClientConnection> selectedConnections = new ArrayList<NHttpClientConnection>();
for (String host : hostList) {
try {
String[] params = host.split(":");
for (HttpRoute httpRoute : connMap.keySet()) {
if (params.length > 1 && params[0].equalsIgnoreCase(httpRoute.getTargetHost().getHostName())
&& (Integer.valueOf(params[1]) == (httpRoute.getTargetHost().getPort())) &&
httpRoute.getTargetHost().getSchemeName().equalsIgnoreCase(SSL_SCHEMA_NAME)) {
List<NHttpClientConnection> clientConnections = connMap.get(httpRoute);
if (clientConnections != null) {
int count = 0;
for (NHttpClientConnection nHttpClientConnection : clientConnections) {
selectedConnections.add(clientConnections.get(count));
count++;
}
}
}
}
} catch (NumberFormatException e) {
if(log.isWarnEnabled()) {
log.warn("Error in port number in host:port - " + host + " discard connection loading ", e);
}
}
}
return selectedConnections;
}
}