如何通过故障转移传输处理Activemq的最大帧大小异常
我正在开发一个使用activemq来交换消息的应用程序,这个消息有点大,我想要取消。如何通过故障转移传输处理Activemq的最大帧大小异常
我们使用带有两个ActiveMQ实例(主/从)的activemq故障转移传输。代理本身具有100mb的消息框架限制。
问题是:如果我尝试发送大于100mb的消息,ActiveMQ服务器将关闭连接。此时,故障转移传输将尝试重新连接并再次发送消息,从而创建无限循环。
客户端登录如下:
2017-01-05 09:19:11.910 WARN 14680 --- [0.1:[email protected]] o.a.a.t.failover.FailoverTransport : Transport (tcp://localhost:61616) failed , attempting to automatically reconnect: {}
java.io.EOFException: null
at java.io.DataInputStream.readInt(DataInputStream.java:392) ~[na:1.8.0_91]
at org.apache.activemq.openwire.OpenWireFormat.unmarshal(OpenWireFormat.java:267) ~[activemq-client-5.13.4.jar:5.13.4]
at org.apache.activemq.transport.tcp.TcpTransport.readCommand(TcpTransport.java:240) ~[activemq-client-5.13.4.jar:5.13.4]
at org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:232) ~[activemq-client-5.13.4.jar:5.13.4]
at org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:215) ~[activemq-client-5.13.4.jar:5.13.4]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_91]
2017-01-05 09:19:11.921 INFO 14680 --- [ActiveMQ Task-1] o.a.a.t.failover.FailoverTransport : Successfully reconnected to tcp://localhost:61616
2017-01-05 09:19:11.923 WARN 14680 --- [0.1:[email protected]] o.a.a.t.failover.FailoverTransport : Transport (tcp://localhost:61616) failed , attempting to automatically reconnect: {}
java.io.EOFException: null
at java.io.DataInputStream.readInt(DataInputStream.java:392) ~[na:1.8.0_91]
at org.apache.activemq.openwire.OpenWireFormat.unmarshal(OpenWireFormat.java:267) ~[activemq-client-5.13.4.jar:5.13.4]
at org.apache.activemq.transport.tcp.TcpTransport.readCommand(TcpTransport.java:240) ~[activemq-client-5.13.4.jar:5.13.4]
at org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:232) ~[activemq-client-5.13.4.jar:5.13.4]
at org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:215) ~[activemq-client-5.13.4.jar:5.13.4]
at java.lang.Thread.run(Thread.java:745) [na:1.8.0_91]
虽然ActiveMQ的实例日志:
2017-01-05 09:19:11,909 | WARN | Transport Connection to: tcp://127.0.0.1:57025 failed: java.io.IOException: Frame size of 363 MB larger than max allowed 100 MB | org.apache.activemq.broker.TransportConnection.Transport | ActiveMQ Transport: tcp:///127.0.0.1:[email protected]
2017-01-05 09:19:11,922 | WARN | Transport Connection to: tcp://127.0.0.1:57026 failed: java.io.IOException: Frame size of 363 MB larger than max allowed 100 MB | org.apache.activemq.broker.TransportConnection.Transport | ActiveMQ Transport: tcp:///127.0.0.1:[email protected]
我试图建立一个TransportListener来验证,如果我能捕捉到这种情况,但我只收到transportInterupted事件,没有任何分类器。
我阅读了有关故障转移传输的文档(http://activemq.apache.org/failover-transport-reference.html),也许我可以使用maxReconnectAttempts,但我知道在更常见的情况下(如服务器暂时不可用)会有一些缺陷。
如何检测这种情况并避免客户端和服务器之间的无限连接循环?
至于你说的这种方式
maxReconnectAttempts -1 | 0从ActiveMQ 5.6:默认是-1,永久重试。 0意味着禁用重新连接,例如:只是尝试连接一次。在ActiveMQ之前 5.6:默认为0,请重试。所有ActiveMQ版本:值> 0表示错误发送回客户端之前的重新连接尝试的最大次数为 。
所以,如果你想失败重试后要通知你的传输监听传输失败的,由于你的信息,你需要在那之后maxReconnectAttempts设置的值> 0时的最大重试次数达到的方法onException的大小您的传输侦听器将被调用IOException作为参数,但正如您所说的,验证它是否由于最大值或其他问题并不容易。
如果你想通过JMX访问它来检查发送你可以得到maxFrameSize在运行时的代理方的URI配置之前提议的消息大小并获得BrokerViewMBean实例,并调用getTransportConnectorByType方法http://activemq.apache.org/maven/apidocs/src-html/org/apache/activemq/broker/jmx/BrokerViewMBean.html#line.304这将返回uri在activemq.xml中配置,您可以解析它以检索maxFrameSize。
JMXServiceURL url = new JMXServiceURL("service:jmx:rmi:///jndi/rmi://hist:1099/jmxrmi");
JMXConnector jmxc = JMXConnectorFactory.connect(url);
MBeanServerConnection conn = jmxc.getMBeanServerConnection();
ObjectName activeMq = new ObjectName("org.apache.activemq:Type=Broker,BrokerName=localhost");
BrokerViewMBean mbean = (BrokerViewMBean)MBeanServerInvocationHandler.newProxyInstance(conn, activeMq, BrokerViewMBean.class, true);
String uri = mbean.getTransportConnectorByType("tcp");// or ("ssl")
String[] pairs = uri.split("&");
for (String pair : pairs) {
if (pair.startsWith("wireFormat.maxFrameSize")) {
int idx = pair.indexOf("=");
System.out.println(URLDecoder.decode(pair.substring(idx + 1), "UTF-8"));
}
}
http://activemq.apache.org/maven/apidocs/org/apache/activemq/broker/jmx/BrokerViewMBean.html#getTransportConnectors--会返回地图运输名称作为关键字和URI的作为值
有消息的更好的大小,你可以这样做:
OpenWireFormat opf = new OpenWireFormat();
opf.setTightEncodingEnabled(true);
ByteSequence tab = opf.marshal(message);
System.out.println(tab.length);
您的企业必须是像这样:
import java.io.IOException;
import java.net.URLDecoder;
import java.util.HashMap;
import java.util.Map;
import javax.jms.Connection;
import javax.jms.JMSException;
import javax.jms.MessageProducer;
import javax.management.MBeanServerConnection;
import javax.management.MBeanServerInvocationHandler;
import javax.management.ObjectName;
import javax.management.remote.JMXConnector;
import javax.management.remote.JMXConnectorFactory;
import javax.management.remote.JMXServiceURL;
import org.apache.activemq.ActiveMQConnection;
import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.ActiveMQSession;
import org.apache.activemq.broker.jmx.BrokerViewMBean;
import org.apache.activemq.command.ActiveMQTextMessage;
import org.apache.activemq.openwire.OpenWireFormat;
import org.apache.activemq.transport.TransportFilter;
import org.apache.activemq.transport.TransportListener;
import org.apache.activemq.transport.failover.FailoverTransport;
import org.apache.activemq.util.ByteSequence;
public class SimpleSenderMaxSizeManager {
private static Connection conn = null;
private static boolean transportChanged;
private static Long MAX_FRAME_SIZE;
public static void main(String[] args) throws JMSException {
try {
SimpleSenderMaxSizeManager.updateMaxSize("host1");
ActiveMQConnectionFactory cf = new ActiveMQConnectionFactory(
"failover:(tcp://host1:5670,tcp://host2:5671)?randomize=false");
cf.setTransportListener(new TransportListener() {
@Override
public void transportResumed() {
if (transportChanged) {
transportChanged = false;
try {
SimpleSenderMaxSizeManager.updateMaxSize(null);
} catch (Exception e) {
}
}
}
@Override
public void transportInterupted() {
transportChanged = true;
}
@Override
public void onException(IOException error) {
}
@Override
public void onCommand(Object command) {
}
});
conn = cf.createConnection();
ActiveMQSession session = (ActiveMQSession) conn.createSession(false,
ActiveMQSession.INDIVIDUAL_ACKNOWLEDGE);
MessageProducer producer = session.createProducer(session.createQueue("TEST"));
conn.start();
ActiveMQTextMessage msg = (ActiveMQTextMessage) session.createTextMessage("test");
OpenWireFormat opf = new OpenWireFormat();
opf.setTightEncodingEnabled(true);
ByteSequence tab = opf.marshal(msg);
System.out.println(tab.length);
if (tab.length >= MAX_FRAME_SIZE) {
throw new RuntimeException(tab.length + ">=" + MAX_FRAME_SIZE);
}
producer.send(msg);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (conn != null) {
try {
conn.close();
} catch (Exception e) {
}
}
}
}
protected static void updateMaxSize(String host) throws Exception {
JMXConnector jmxc = null;
try {
String jmxHost = host;
String scheme = null;
if (conn == null) {
scheme = "tcp";
} else {
org.apache.activemq.transport.TransportFilter responseCorrelator = (TransportFilter) ((ActiveMQConnection) conn)
.getTransport();
TransportFilter mutexTransport = (TransportFilter) responseCorrelator.getNext();
FailoverTransport failoverTransport = (FailoverTransport) mutexTransport.getNext();
while (failoverTransport.getConnectedTransportURI() == null) {
try {
Thread.sleep(100);
} catch (Exception e) {
}
}
scheme = failoverTransport.getConnectedTransportURI().getScheme();
jmxHost = failoverTransport.getConnectedTransportURI().getHost();
}
JMXServiceURL url = new JMXServiceURL("service:jmx:rmi:///jndi/rmi://" + jmxHost + ":1099/jmxrmi");
Map<String, String[]> env = new HashMap<>();
String[] creds = { "admin", "admin" };
env.put(JMXConnector.CREDENTIALS, creds);
jmxc = JMXConnectorFactory.connect(url, env);
MBeanServerConnection conn = jmxc.getMBeanServerConnection();
ObjectName activeMq = new ObjectName("org.apache.activemq:type=Broker,brokerName=localhost");
BrokerViewMBean mbean = MBeanServerInvocationHandler.newProxyInstance(conn, activeMq, BrokerViewMBean.class,
true);
String value = mbean.getTransportConnectorByType(scheme);
String[] pairs = value.split("&");
for (String pair : pairs) {
if (pair.contains("wireFormat.maxFrameSize")) {
int idx = pair.indexOf("=");
System.out.println(URLDecoder.decode(pair.substring(idx + 1), "UTF-8"));
MAX_FRAME_SIZE = Long.valueOf(URLDecoder.decode(pair.substring(idx + 1), "UTF-8"));
MAX_FRAME_SIZE -= 1000;// security for JMS headers added by
// session on sending
}
}
} finally {
if (jmxc != null) {
try {
jmxc.close();
} catch (Exception e) {
}
}
}
}
}
我不相信这是可能的。您正在尝试对错误处理进行分类,以查找不会因故障转移而发生故障的异常:传输。如果超出最大客户端数量,则可能会发生相同类型的异常。
在发送声音之前检查消息大小是否可行。
是否有原因尺寸检查不符合您的要求?
public String mySendMessage(String body) {
....
if(body.length > MAX_ALLOWED) ..
throw new Exception.. or log.. or other
else
producer.send(session.createTextMessage(body));
这个问题对我来说是w e在客户端驱动程序和activemq之间创建一个我无法处理或干扰的循环。 –
关于您的问题:checkint问题在发送之前,消息的大小是我不知道activemq实例允许的最大大小是多少。在其他作品中,我可以更改activemq的配置,但我也需要更改应用程序的配置。它更容易出错。 –
如何获取邮件有效负载的大小? (请参阅我的编辑上面的一些JMS-API伪代码) –
相当不错的答案。我认为解决方案将通过JMX检查正确的框架。问题:opf.marshal(message);将序列化整个消息只是为了获得它的大小?如果我有一个巨大的消息大小,这可能是一个缺点(尽管我使用getBytes(“UTF-8”)仅用于测试。 –
是啊opf.marshal(消息);是AMQ客户端发送之前所使用的将整个消息与头部编组在一起,以获得接近真实的大小。在所有情况下,AMQ会稍后使用此方法,并且我认为这对您是否有用以确定它是否正常工作 –