- transport connectors which consist of transport channels and wire formats TODO: add a link to a page explaining what transport connectors are how to configure and use them.
- network connectors using network channels or discovery TODO: add a link to a page explaining what network connectors are how to configure and use them.
- discovery agents TODO: add a link to a page explaining what discovery agents are how to configure and use them.
- persistence providers & locations TODO: add a link to a page explaining what persistence providers are how to configure and use them.
- custom message containers (such as last image caching etc)
We use XBean to perform the XML configuration.
For details of the XML see the Xml Reference
Be careful with broker names and URIsMake sure you do not use any strange characters in the names of brokers as they are converted to URIs which do not allow things like underscores in them etc.
Examples
The default ActiveMQ configuration: current default config.
xml<beans
xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://activemq.apache.org/schema/core http://activemq.apache.org/schema/core/activemq-core.xsd">
<!-- Allows us to use system properties as variables in this configuration file -->
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="locations">
<value>file:${activemq.conf}/credentials.properties</value>
</property>
</bean>
<!-- Allows accessing the server log -->
<bean id="logQuery" class="io.fabric8.insight.log.log4j.Log4jLogQuery"
lazy-init="false" scope="singleton"
init-method="start" destroy-method="stop">
</bean>
<!--
The <broker> element is used to configure the ActiveMQ broker.
-->
<broker xmlns="http://activemq.apache.org/schema/core" brokerName="localhost" dataDirectory="${activemq.data}">
<destinationPolicy>
<policyMap>
<policyEntries>
<policyEntry topic=">" >
<!-- The constantPendingMessageLimitStrategy is used to prevent
slow topic consumers to block producers and affect other consumers
by limiting the number of messages that are retained
For more information, see:
http://activemq.apache.org/slow-consumer-handling.html
-->
<pendingMessageLimitStrategy>
<constantPendingMessageLimitStrategy limit="1000"/>
</pendingMessageLimitStrategy>
</policyEntry>
</policyEntries>
</policyMap>
</destinationPolicy>
<!--
The managementContext is used to configure how ActiveMQ is exposed in
JMX. By default, ActiveMQ uses the MBean server that is started by
the JVM. For more information, see:
http://activemq.apache.org/jmx.html
-->
<managementContext>
<managementContext createConnector="false"/>
</managementContext>
<!--
Configure message persistence for the broker. The default persistence
mechanism is the KahaDB store (identified by the kahaDB tag).
For more information, see:
http://activemq.apache.org/persistence.html
-->
<persistenceAdapter>
<kahaDB directory="${activemq.data}/kahadb"/>
</persistenceAdapter>
<!--
The systemUsage controls the maximum amount of space the broker will
use before disabling caching and/or slowing down producers. For more information, see:
http://activemq.apache.org/producer-flow-control.html
-->
<systemUsage>
<systemUsage>
<memoryUsage>
<memoryUsage percentOfJvmHeap="70" />
</memoryUsage>
<storeUsage>
<storeUsage limit="100 gb"/>
</storeUsage>
<tempUsage>
<tempUsage limit="50 gb"/>
</tempUsage>
</systemUsage>
</systemUsage>
<!--
The transport connectors expose ActiveMQ over a given protocol to
clients and other brokers. For more information, see:
http://activemq.apache.org/configuring-transports.html
-->
<transportConnectors>
<!-- DOS protection, limit concurrent connections to 1000 and frame size to 100MB -->
<transportConnector name="openwire" uri="tcp://0.0.0.0:61616?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/>
<transportConnector name="amqp" uri="amqp://0.0.0.0:5672?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/>
<transportConnector name="stomp" uri="stomp://0.0.0.0:61613?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/>
<transportConnector name="mqtt" uri="mqtt://0.0.0.0:1883?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/>
<transportConnector name="ws" uri="ws://0.0.0.0:61614?maximumConnections=1000&wireFormat.maxFrameSize=104857600"/>
</transportConnectors>
<!-- destroy the spring context on shutdown to stop jetty -->
<shutdownHooks>
<bean xmlns="http://www.springframework.org/schema/beans" class="org.apache.activemq.hooks.SpringContextHook" />
</shutdownHooks>
</broker>
<!--
Enable web consoles, REST and Ajax APIs and demos
The web consoles requires by default login, you can disable this in the jetty.xml file
Take a look at ${ACTIVEMQ_HOME}/conf/jetty.xml for more details
-->
<import resource="jetty.xml"/>
</beans>From a binary distribution there is an activemq script allowing you to run a Message Broker as a stand alone process from the command line easily providing the $ACTIVEMQ_HOME/bin directory is on your PATH.
Configuring embedded brokers
You can also use the XML Configuration to configure embedded brokers. For example using the JNDI configuration mechanism you can do the following
BrokerXmlConfigFromJNDITest
Or of you want to explicitly configure the embedded broker via Java code you can do the following
BrokerXmlConfigTest
User Submitted Configurations
We have a page which allows users to submit details of their configurations.
Background
Since ActiveMQ has so many strategy pattern plugins for transports, wire formats, persistence and many other things, we wanted to leave the configuration format open so that you the developer can configure and extend ActiveMQ in any direction you wish.
So we use the Spring XML configuration file format, which allows any beans / POJOs to be wired together and configured. However often Spring's XML can be kinda verbose at times, so we have implemented an ActiveMQ extension to the Spring XML which knows about the common, standard ActiveMQ things you're likely to do (e.g. tags like connector, wireFormat, serverTransport, persistence) - but at any time you can fall back to the normal Spring way of doing things (with tags like bean, property etc).
To see documentation of the XML file we use or to get access to the XSD/DTD see the Xml Reference