GraphAcademy

Building Neo4j Applications with Spring Data

Getting Started

The Application Domain Model

Reading Data from Neo4j

Writing Data to Neo4j

Custom Cypher for Read and Write

Next Steps

Challenge: Create Person repository and controller

Your challenge is to create a Person repository interface and controller class to access the person entities in the database. Then, you will check your work by testing the application and finding a person node.

PersonRepository

In the src/main/java/com/example/appspringdata directory, create an interface called PersonRepository.java that extends the Neo4jRepository interface with the appropriate domain and identifier types.

Completed code is available below for verification.

Click to reveal the completed PersonRepository interface code
java
import org.springframework.data.neo4j.repository.Neo4jRepository;

public interface PersonRepository extends Neo4jRepository<Person, String> {
}

PersonController

In the same directory, add a new class called PersonController.java with proper annotations (/people main endpoint) and create methods to implement findAll() and findById() for Person entities.

Completed code is available below.

Click to reveal the completed PersonController class code
java
import java.util.Optional;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.PathVariable;

@RestController
@RequestMapping("/people")
public class PersonController {
    private final PersonRepository personRepo;

    public PersonController(PersonRepository personRepo) {
        this.personRepo = personRepo;
    }

    @GetMapping()
    Iterable<Person> findAllPeople() {
        return personRepo.findAll();
    }

    @GetMapping("/{imdbId}")
    Optional<Person> findPersonById(@PathVariable String imdbId) {
        return personRepo.findById(imdbId);
    }
}

Test the application

With those pieces in place, you can now test the application. Run the application and execute the following commands in the terminal to see the results.

shell
curl 'localhost:8080/people'
curl 'localhost:8080/people/0000245'

Summary

In this lesson, you created repository and controller classes to access Person entities in the database. You also ran and tested the application, using an API to call repository methods, query the database, and return the results.

Next, you will map the relationships between Movie and Person entities.