Service task that runs groovy scripts from deployment resources

I have created a service task that retrieves a groovy script from the deployment resources. I am hoping someone can have a look and tell me if I am going to run into trouble :slight_smile:

This is just a first draft so the caching is rudimentary for now…

public class GroovyDeploymentResourceDelegate extends TaskActivityBehavior {
    private static final long serialVersionUID = 1L;
    private static final String LANGUAGE= "groovy";
    private static ConcurrentHashMap<String, String> cachedScripts = new ConcurrentHashMap<>();

    public void execute(DelegateExecution execution) {
        String key = execution.getProcessDefinitionId() + "::" + execution.getCurrentActivityId();
        String script = cachedScripts.get(key);
        if (script == null) {
            try {
                RepositoryService repositoryService = CommandContextUtil.getProcessEngineConfiguration().getRepositoryService();
                ProcessDefinition processDefinition = repositoryService.getProcessDefinition(execution.getProcessDefinitionId());
                String className = execution.getCurrentFlowElement().getName();
                String resourceName = className + "." + LANGUAGE;
                InputStream in = repositoryService.getResourceAsStream(processDefinition.getDeploymentId(), resourceName);
                script = IOUtils.toString(in, StandardCharsets.UTF_8);
                // Execute the script
                script += "\nnew " + className + "().execute(execution)";
                cachedScripts.put(key, script);
            } catch (Exception e) {
                throw new RuntimeException("Could not load script for " + execution.getCurrentFlowElement().getName(), e);

        new ScriptTaskActivityBehavior(script, LANGUAGE, null).execute(execution);

We’d then define a script like this:

class DoSomething implements JavaDelegate {
    def static logger = Logger.getLogger(DoSomething.class)
    def void execute(DelegateExecution execution) {"Doing something")
    def doSomethingMore() {"I get to call methods")

And just package that in DoSomething.groovy inside the zip file with the processes.

I should probably say why I am doing this. It is to improve the development process of scripts. We get to write a groovy script in the IDE and not have to copy the contents into a script task. It is also a class and is nice for unit testing in isolation. If we wanted to we can use a compiled version as well, but sticking to scripts for now for ease and flexibility of deployment.