Now that you can communicate between your controller and your data access layer, you’ve bridged the gap between an end user of your API and the database.

One of the fastest ways to test this functionality is by implementing some GET endpoints in the controller. The GET request should be used to retrieve information out of your database, so it makes sense that a GET request should trigger repository methods like .findAll() or .findById(Integer id).

Continuing the example of the Person model, our PersonController may include some @GetMappings to accomplish this:

import java.lang.Iterable;
import java.util.Optional;

import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.GetMapping;

import com.codecademy.people.entities.Person;
import com.codecademy.people.repositories.PersonRepository;

@RestController
public class PersonController {

  private final PersonRepository personRepository;

  public PersonController(final PersonRepository personRepository) {
    this.personRepository = personRepository;
  }

  @GetMapping("/people")
  public Iterable<Person> getAllPeople() {
    return this.personRepository.findAll();
  }

  @GetMapping("/people/{id}")
  public Optional<Person> getPersonById(@PathVariable("id") Integer id) {
    return this.personRepository.findById(id);
  }

}

In this example, the "/people" endpoint of this API will fetch all Person entries from the PersonRepository using the .findAll() method offered by the CrudRepository. It returns an Iterable, which is just a simplified interface for a collection in Java. Note that the Iterable has a type parameter, Person.

You would test this functionality by making a GET request with curl, or even navigating to that endpoint in a web browser!

curl localhost:4001/people

# [
#   {
#     "id": 1,
#     "eyeColor": "green",
#     "name": "Tammy Green",
#     "age": 31
#   },
#   {
#     "id": 2,
#     "eyeColor": "hazel",
#     "name": "Rashid Jordan",
#     "age": 14
#   },
#   {
#     "id": 3,
#     "eyeColor": "brown",
#     "name": "Aneeqa Kumar",
#     "age": 23
#   }
# ]

If, at any point, you see an error like “Failed to connect to localhost port 4001: Connection refused”, your Spring server may be malfunctioning. Fix all errors in your code, and run your code before executing the command pkill ein in the terminal to reset the server. Your browser will disconnect and reconnect to Codecademy.