Spring Boot MongoRepository findAll() returns empty array

Question

I have a Spring Boot application connected to the local Mongo database, but when I try to fetch all the documents from a collection by requesting http://localhost:8080/api/v1/users it returns an empty array. I don't have any connection errors as well. I've read that the problem could've been with collection names, but when I specified collection name (and now collection name in MongoDB is the same as in the model), it still returns an empty array. What else could've been wrong?

Model:

@Document(collection = "users")
public class User {

    @Id
    private String id;

    private String username;
    private String email;
    private String password;
    private String birthdate;

    private int chest;
    private int weight;
    private int height;
    private boolean gender;

    // constructors, getters and setters omitted
}

Controller:

@RestController
@RequestMapping("api/v1/users")
public class UserController {

    private final UserService userService;

    @Autowired
    public UserController(UserService userService) {
        this.userService = userService;
    }

    @GetMapping
    public List<User> findAll() {
        return userService.find();
    }
}

Service:

@Service
public class UserService {

    @Autowired
    private UserRepository userRepository;

    public List<User> find() {
        return userRepository.findAll();
    }
}

Repository:

public interface UserRepository extends MongoRepository<User, String> {
    public User findByEmail(String email);
}

Straight from MongoDB:

> db.users.find().pretty()
{
    "_id" : ObjectId("60002a15803d9027a459b7b6"),
    "username" : "name",
    "email" : "zaaas@sasasfa.aaa",
    "birthdate" : "1999-10-2",
    "weight" : 67,
    "height" : 175,
    "chest" : 87,
    "gender" : true,
    "__v" : 0
}
{
    "_id" : ObjectId("60002be21da6d929fa45c9f2"),
    "username" : "aye",
    "email" : "zaaas@sasasfsdsa.aaa",
    "birthdate" : "1999-10-2",
    "weight" : 65,
    "height" : 180,
    "chest" : 80,
    "gender" : true,
    "__v" : 0
}

EDIT

The problem was with my connection properties.

Before:

# application.yml, started using yaml just for better readability,
# should work as fine with application.properties
spring:
  data:
    mongodb:
      url: mongodb://localhost:27017/{dbname}

After:

# application.yml
spring:
  data:
    mongodb:
      host: localhost
      port: 27017
      database: {dbname}

Answer 1

The issue arises because the collection name is not explicitly given in your model.Can you change your code like below

@Document(collection = "User")
public class User {

    @Id
    private String id;

    private String username;
    private String email;
    private String password;
    private String birthdate;

    private int chest;
    private int weight;
    private int height;
    private boolean gender;

    // constructors, getters and setters omitted
}