ActiveMQ JMS Event Publisher

ActiveMQ JMS event publisher is used to publish events in map, XML, JSON, and text formats via JMS transport.

Prerequisites

Follow the steps below to set up the prerequisites before starting the configuration.

Install Apache ActiveMQ JMS.

This guide uses ActiveMQ versions 5.7.0 or below. If you want to use a later version, for instructions on the necessary changes to the configuration steps, go to Apache ActiveMQ Documentation.
Configure WSO2 CEP by adding relevant libraries to support JMS transport.
Refer the <PRODUCT_HOME>/repository/conf/jndi.properties file to register a connection factory. For example, if the connection factory JNDI name is TopicConnectionFactory, it will point the default ActiveMQ host to localhost and port to 5672 as shown below. Furthermore, add the topics to be sent to the ActiveMQ broker in the format: topic.{topicName} = {topicName}
```
connectionfactory.TopicConnectionFactory=amqp://admin:admin@clientid/test?brokerlist='tcp://localhost:5672'
topic.topicMap = topicMap
topic.topicText = topicText
```
Start ActiveMQ, and then start the product.

Creating an ActiveMQ JMS event publisher

For instructions on creating an ActiveMQ JMS event publisher, see Configuring CEP to Create Alerts.

Configuring adapter properties

Specify the Static and Dynamic Adapter Properties, when creating an ActiveMQ JMS event publisher using the management console as shown below.

ActiveMQ JMS Publisher

After entering the above adapter properties, select the Message Format which you want to apply on the published events . Also, click Advanced to define custom output mappings based on the Message Format you selected. For more information on custom output mapping types, see Publishing Events in Various Event Formats.

You can also define the respective adapter properties of the event publisher based on the transport type within the <to> element of the event publisher configuration in the <PRODUCT_HOME>/repository/deployment/server/eventpublishers/ directory as follows.

<eventPublisher name="ActiveMQJMSOutputEventAdapter" statistics="disable" trace="disable" xmlns="http://wso2.org/carbon/eventpublisher">
  .................
  <to eventAdapterType="jms">
    <property name="java.naming.factory.initial">org.apache.activemq.jndi.ActiveMQInitialContextFactory</property>
    <property name="java.naming.provider.url">tcp://localhost:61616</property>
    <property name="transport.jms.UserName">jms-user</property>
    <property encrypted="true" name="transport.jms.Password">ImE/+i4TR0c7p97CWbd8bUgfXfC8XcKWVwIwXxw+ROUFvxOR3+61S6YXqZK7dkKTLgBBFNmB2czfSiJrUz9jCYxFXSUquCfqFs8UKXx3976sjmM+giTTyPJnyCNilceF2fMPZ0abOJdq7gD+zi9IeoX14EPnZUuY9sOUOGFg7B8=</property>
    <property name="transport.jms.DestinationType">topic</property>
    <property name="transport.jms.Header">header_name1:header_value1,header_name2:header_value2</property>
    <property name="transport.jms.Destination">topicMap</property>
    <property name="transport.jms.ConnectionFactoryJNDIName">TopicConnectionFactory</property>
  </to>
</eventPublisher>

The above adapter properties are described below.

Static adapter properties

Adapter Property	Description	Configuration file property	Example
JNDI Initial Context Factory Class	The JNDI initial context factory class. The class must implement the `java.naming.spi.InitialContextFactory` interface	java.naming.factory.initial	org.apache.activemq.jndi.ActiveMQInitialContextFactory
JNDI Provider URL	URL of the JNDI provider	java.naming.provider.url	tcp://localhost:61616
Username	Valid username for the JMS connection	transport.jms.UserName	jms-user
Password	Valid password for the JMS connection	transport.jms.Password	jms-password
Connection Factory JNDI Name	The JNDI name of the connection factory	transport.jms.ConnectionFactoryJNDIName	TopicConnectionFactory
Destination Type	The sort order for messages that arrive on a specific destination	transport.jms.DestinationType	topic/queue
Destination	The topic or queue to which WSO2 CEP sends messages by publishing.	transport.jms.Destination	topicMap
Concurrent Publishers	If concurrent publishers are allowed to publish events to a JMS broker using multiple threads.	`transport.jms.ConcurrentPublishers`	allow

Dynamic adapter properties

Adapter Property	Description	Configuration file property	Example
Header	Define Transport Headers as a valid header name in a header value pair format	`transport.jms.Header`	header_name1:header_value1,header_name2:header_value2

Related samples

For more information on ActiveMQ event publisher type, see the following sample.

Sample 0059 - Publishing Map and Text Events via JMS Transport - ActiveMQ