2 Get Started

2.1 Install the plugin

plugins {
    compile ":camunda:0.5.0"
}

You may want to refresh your dependencies now in order to make sure that Grails properly installs the plugin. Type on your command line

grails refresh-dependencies

2.2 Create a process definition

grails create-process [name]

As name choose a 'package and class' like name of your choice, e.g. "org.camunda.my.TestProcess". You should see the following two files generated by Grails:

| Created file grails-app/processes/org/camunda/my/TestProcess.bpmn
| Created file test/integration/org/camunda/my/TestProcessSpec.groovy

You may now want to look at the generated BPMN process definition by making use of camunda modeler. It's a minimal process, to get you started and build upon:

Furthermore you will find a 'spock' based integration spec executing and checking that process. It does have a bit more content than your typical almost empty Grails spec template...

[...]
given: "a new instance of TestProcess"
runtimeService.startProcessInstanceByKey("TestProcess")
when: "completing the user task"
def task = taskService.createTaskQuery().singleResult()
taskService.complete(task.id)
then: "the service method defined for the subsequent service task was called exactly once"
1 * sampleTestProcessService.serviceMethod(_ as Execution)
[...]

… again to get you started with typical process testing boilerplate readily adapted to your freshly created process definition and to build upon. You can directly execute that test:

2.3 Execute the integration test

Beware that this test will populate your test environment database with camunda related tables. By default, this will be a H2 in memory database preconfigured by Grails - so everything fine with that. For other databases, you will need to adapt the plugin configuration, too.

grails test-app integration: org.camunda.my.TestProcess

When executing the test you should see the following familiar output :-)

| Running 1 integration test… 1 of 1
| Completed 1 integration test, 0 failed in 0m 0s
| Tests PASSED - view reports in ./target/test-reports

Congrats! You are successfully using an embedded camunda BPM engine with the Grails framework! If you want to use camunda "behind the scenes" of your grails app that's all that is needed! But maybe you …

2.4 Wanna see camunda BPM in action?

./start-camunda.sh

Now, return to your your grails project command line, and create a 'war' file prepared to use the process engine managed by the camunda BPM tomcat container and shared with your grails app:

grails war

Move the war generated in your target folder into the camunda BPM tomcat 'webapp' folder. Open http://localhost:8080/camunda-welcome and navigate to the tasklist application. Log in with user 'demo', password 'demo' and start your new process via the (little bit hidden :-) "start process" button in the top right corner:

The sample form shows you different types of fields. You must at least select one of the values in the 'sampleRequiredSelectionField' in order to validate the start form and enable the "Start"-Button. Start the process and you should see the "Sample UserTask" of your process assigned to you as user "demo". You may want to check out the diagram pane of your process and then complete the task via the form. This will execute the subsequent service task (which logs the process variables provided by you into your tomcats logs/catalina.out file) and immediately after that finish your process instance.