DataSet Component

Testing of distributed and asynchronous processing is notoriously difficult. The Mock, Test and DataSet endpoints work great with the Camel Testing Framework to simplify your unit and integration testing using Enterprise Integration Patterns and Camel's large range of Components together with the powerful Bean Integration.

The DataSet component (available since 1.3.0) provides a mechanism to easily perform load & soak testing of your system. It works by allowing you to create DataSet instances both as a source of messages and as a way to assert that the data set is received.

Camel will use the throughput logger when sending dataset's.

URI format

dataset:name[?options]

Where name is used to find the DataSet instance in the Registry

Camel ships with a support implementation of org.apache.camel.component.dataset.DataSet, the org.apache.camel.component.dataset.DataSetSupport class, that can be used as a base for implementing your own DataSet. Camel also ships with a default implementation, the org.apache.camel.component.dataset.SimpleDataSet that can be used for testing.

Options

Option Default Description
produceDelay 3 Allows a delay in ms to be specified, which causes producers to pause in order to simulate slow producers. Uses a minimum of 3 ms delay unless you set this option to -1 to force no delay at all.
consumeDelay 0 Allows a delay in ms to be specified, which causes consumers to pause in order to simulate slow consumers.
preloadSize 0 Sets how many messages should be preloaded (sent) before the route completes its initialization.

You can append query options to the URI in the following format, ?option=value&option=value&...

Configuring DataSet

Camel will lookup in the Registry for a bean implementing the DataSet interface. So you can register your own DataSet as:

<bean id="myDataSet" class="com.mycompany.MyDataSet">
      <property name="size" value="100"/>
   </bean>

Example

For example, to test that a set of messages are sent to a queue and then consumed from the queue without losing any messages:

// send the dataset to a queue
from("dataset:foo").to("activemq:SomeQueue");

// now lets test that the messages are consumed correctly
from("activemq:SomeQueue").to("dataset:foo");

The above would look in the Registry to find the foo DataSet instance which is used to create the messages.

Then you create a DataSet implementation, such as using the SimpleDataSet as described below, configuring things like how big the data set is and what the messages look like etc.

Properties on SimpleDataSet

Property Type Description
defaultBody Object Specifies the default message body. For SimpleDataSet it is a constant payload; though if you want to create custom payloads per message, create your own derivation of DataSetSupport.
reportGroup long Specifies the number of messages to be received before reporting progress. Useful for showing progress of a large load test.
size long Specifies how many messages to send/consume.

Load testing ActiveMQ with Camel

There is an example of load testing an ActiveMQ queue using Camel in the ActiveMQ source code repository. The code lives at this location:

You can grab the code as follows:

svn co https://svn.apache.org/repos/asf/activemq/trunk/activemq-camel-loadtest/

Then try running the test case:

cd activemq-camel-loadtest
mvn clean install

To see how the test is defined, see the Spring XML file

<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-2.0.xsd
       http://camel.apache.org/schema/spring http://camel.apache.org/schema/spring/camel-spring.xsd
       http://activemq.apache.org/schema/core http://activemq.apache.org/schema/core/activemq-core.xsd
    ">

  <camelContext xmlns="http://camel.apache.org/schema/spring">

    <route>
      <!-- sends messages every 10 milliseconds -->
      <from uri="dataset:myDataSet?produceDelay=10"/>
      <to uri="activemq:test.queue"/>
    </route>

    <route>
      <from uri="activemq:test.queue"/>
      <to uri="dataset:myDataSet?produceDelay=10"/>
    </route>

  </camelContext>

  <bean id="myDataSet" class="org.apache.camel.component.dataset.SimpleDataSet">
    <property name="size" value="10000"/>
    <property name="reportCount" value="100"/>
  </bean>

  <!-- lets create an embedded broker for this test -->
  <broker xmlns="http://activemq.apache.org/schema/core" dataDirectory="target/activemq">

    <transportConnectors>
       <transportConnector uri="tcp://localhost:61616"/>
    </transportConnectors>

  </broker>

  <!-- Lets connect the Camel ActiveMQ component to the embedded broker.
    See http://activemq.apache.org/camel/activemq.html for more information.
  -->
  <bean id="activemq" class="org.apache.activemq.camel.component.ActiveMQComponent">
    <property name="brokerURL" value="tcp://localhost:61616" />
  </bean>
</beans>

See Also

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