在 Mule 4 中调用 groovy 方法

Question

I have built a complete groovy project with JPA repo for data persistence operations. Now I want to invoke the methods from the script in Mule 4 without changing anything in the groovy project.

eg. CustomerService.groovy (pseudo code)

import com.example.dao.CustomerDao.groovy
... other imports...

@Service
class CustomerService {
@Autowired
CustomerDao cDao

@Transactional
publid Customer createCustomer(Customer customer) {
    return cDao.save(customer)
}

... other methods...
}

CustomerDao.groovy

import spring.JPA  (the original import path may vary)

@Repository
class CustomerDao implements JPARepository<Customer, Integer> {
}

This project is working in Mule 3. In Mule 3 we have an Invoke component which could be used to invoke the methods from the groovy script. The Mule 4 the Invoke component is compatible only with Java and not groovy.

The Scripting module's ' Execute ' component can invoke a groovy script but not sure how to invoke the method. Is the any work around for this in Mule 4?

Problems occured as of now

1. In ' Execute ' component if I import another file I get the error as

Unalbe to resolve class com.example.dao.CustomerDao
@ line 3 column 1,
import com.example.dao.CustomerDao.groovy
^

Found a solution for similar problem https://help.mulesoft.com/s/article/Compilation-exception-in-Mule4-x-when-using-Groovy-script-with-Import-statement but unable to implement it.

In the article, he developer had an issue with an apache dependency, which he/she could get from mvn repo. I am trying to import a groovy file which I have developed. So unable to add it in the dependency. I tried adding the groovy project in my local repo and fetch it but it didn't work. Moreover, when this Mule 4 application will be deployed on CloudHub it will have an issue as it won't be able to access my local repo.

Need a solution to add a spring-groovy project to Mule 4

Thanks:)

Answer 1

The problem is that the Groovy script executed by the Scripting Module is trying to import a class, which is not in Java's classpath. So it throws the error. The class is in another Groovy source file. What you can do is to compile the Groovy code into an actual Java class. You can try one the methods described in the Groovy documentation to integrate a Maven plugin with your Mule application pom.xml file.

Another alternative if you have a large number of Groovy classes is to create a separate project to build a Jar library, then use the solution from the KB article you mentioned.