Intercepting and Read JMS Messages on Red Hat AMQ

Red Hat AMQ, or its OpenSource version which is ActiveMQ, is a JMS 1.1-compliant messaging system. It consists of a broker and client-side libraries that enable remote communication among distributed client applications. Red Hat AMQ provides numerous connectivity options and can communicate with a wide variety of non-JMS clients through its support of the OpenWire and STOMP wire protocols.

So basically it’s a very reliable messaging system, but there are times where we need to capture whatever messages that comes thru AMQ for some debugging purpose. And I can see that AMQ have an interceptor feature that we can leverage to capturing JMS messages that goes thru AMQ.

https://access.redhat.com/documentation/en-us/red_hat_amq/7.2/html/using_amq_broker/interceptors

Creating an interceptor class is actually quite straight forward, lets start with a simple POM file

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.edw</groupId>
    <artifactId>AmqInterceptor</artifactId>
    <version>1.0-SNAPSHOT</version>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>8</source>
                    <target>8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>org.apache.activemq</groupId>
            <artifactId>artemis-jms-client-all</artifactId>
            <version>2.17.0</version>
        </dependency>

    </dependencies>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

</project>

And a simple java file,

package com.edw;

import org.apache.activemq.artemis.api.core.ActiveMQBuffer;
import org.apache.activemq.artemis.api.core.ActiveMQException;
import org.apache.activemq.artemis.api.core.Interceptor;
import org.apache.activemq.artemis.api.core.Message;
import org.apache.activemq.artemis.core.protocol.core.Packet;
import org.apache.activemq.artemis.core.protocol.core.impl.wireformat.SessionReceiveMessage;
import org.apache.activemq.artemis.core.protocol.core.impl.wireformat.SessionSendMessage;
import org.apache.activemq.artemis.spi.core.protocol.RemotingConnection;

import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.StandardOpenOption;
import java.util.Arrays;
import java.util.List;

public class SimpleInterceptor implements Interceptor {
    public boolean intercept(final Packet packet, final RemotingConnection connection) throws ActiveMQException {

        try {
            if (packet instanceof SessionSendMessage) {
                SessionSendMessage realPacket = (SessionSendMessage) packet;
                Message msg = realPacket.getMessage();

                if((msg.getTimestamp()>0) && msg.getUserID()!=null) {
                    ActiveMQBuffer activeMQBuffer = realPacket.getMessage().getBodyBuffer();

		    // it will write the log to a file. Dont use this, use a real logging mechanism such as slf4j
                    List<String> lines = Arrays.asList( "***** msg in *****", msg.toString(), activeMQBuffer.readNullableSimpleString().toString(), "*****");
                    Files.write(Paths.get("amq.out"), lines, 
						StandardCharsets.UTF_8, StandardOpenOption.CREATE, StandardOpenOption.APPEND);
                }
            }
            else if (packet instanceof SessionReceiveMessage) {
                SessionReceiveMessage realPacket = (SessionReceiveMessage) packet;
                Message msg = realPacket.getMessage();

                if((msg.getTimestamp()>0) && msg.getUserID()!=null) {

		    // it will write the log to a file. Dont use this, use a real logging mechanism such as slf4j
                    List<String> lines = Arrays.asList( "***** msg out *****", msg.toString(), "*****");
                    Files.write(Paths.get("amq.out"), lines, 
						StandardCharsets.UTF_8, StandardOpenOption.CREATE, StandardOpenOption.APPEND);
                }
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return true;
    }
}

Build by using below command,

mvn clean package

And put the created jar file into amq_broker_home/lib folder. Restart AMQ and we can see that messages that goes in and out of AMQ is now can be logged.

Code for this can be found here,

https://github.com/edwin/amq-message-interceptor