Camel Test
As a simple alternative to using Spring Testing or Guice the camel-test module was introduced into the Camel 2.0 trunk so you can perform powerful Testing of your Enterprise Integration Patterns easily.
The camel-test
JAR is using JUnit. There is an alternative camel-testng
JAR (Camel 2.8 onwards) using the TestNG test framework.
Adding to your pom.xml
To get started using Camel Test you will need to add an entry to your pom.xml
JUnit
<dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-test</artifactId> <version>${camel-version}</version> <scope>test</scope> </dependency>
TestNG
Available as of Camel 2.8
<dependency> <groupId>org.apache.camel</groupId> <artifactId>camel-testng</artifactId> <version>${camel-version}</version> <scope>test</scope> </dependency>
You might also want to add slf4j and log4j to ensure nice logging messages (and maybe adding a log4j.properties file into your src/test/resources directory).
<dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <scope>test</scope> </dependency>
Writing your test
You firstly need to derive from the class CamelTestSupport and typically you will need to override the createRouteBuilder() method to create routes to be tested.
Here is an example.
Notice how you can use the various Camel binding and injection annotations to inject individual Endpoint objects - particularly the Mock endpoints which are very useful for Testing. Also you can inject producer objects such as ProducerTemplate or some application code interface for sending messages or invoking services.
JNDI
Camel uses a Registry to allow you to configure Component or Endpoint instances or Beans used in your routes. If you are not using Spring or OSGi then JNDI is used as the default registry implementation.
So you will also need to create a jndi.properties file in your src/test/resources directory so that there is a default registry available to initialise the CamelContext.
Here is an example jndi.properties file
java.naming.factory.initial = org.apache.camel.util.jndi.CamelInitialContextFactory
Dynamically assigning ports
Available as of Camel 2.7
Tests that use port numbers will fail if that port is already on use. AvailablePortFinder
provides methods for finding unused port numbers at runtime.
// Get the next available port number starting from the default starting port of 1024 int port1 = AvailablePortFinder.getNextAvailable(); /* * Get another port. Note that just getting a port number does not reserve it so * we look starting one past the last port number we got. */ int port2 = AvailablePortFinder.getNextAvailable(port1 + 1);
Setup CamelContext once per class, or per every test method
Available as of Camel 2.8
The Camel Test kit will by default setup and shutdown CamelContext per every test method in your test class. So for example if you have 3 test methods, then CamelContext is started and shutdown after each test, that is 3 times.
TestNG
This feature is also supported in camel-testng
Beware
When using this the CamelContext will keep state between tests, so have that in mind. So if your unit tests start to fail for no apparent reason, it could be due this fact. So use this feature with a bit of care.
You may want to do this once, to share the CamelContext between test methods, to speedup unit testing. This requires to use JUnit 4! In your unit test method you have to extend the org.apache.camel.test.junit4.CamelTestSupport
or the org.apache.camel.test.junit4.CamelSpringTestSupport
test class and override the isCreateCamelContextPerClass
method and return true
as shown in the following example: