Instancio ile Unit Test’ler için Sahte Veri Oluşturma

By Cem Dırman On Jun 13, 2024

Unit test yazarken mock(sahte) datalar ile çalışıyoruz. Çünkü amacımız belli bir methodun görevini istediğimiz gibi yaptığını doğrulama istiyoruz.

Sahte veriler üretmek zaman zaman zahmetli bir işlem olabiliyor. Instancio tam olarak bu problemi çözüyor. Yani bizim yerimize verdiğimiz modele göre sahte datalar üretiyor.

Instancio

Instancio verileri üretirken tabii ki veri tiplerinden yararlanıyor. Bunun yanı sıra bu kütüphane ile amacımız sadece sahte data üretmek değil, verinin içeriği de önemli.

Zaten unit test yazarken çoğu durumda, amacımız yazacağımız test methoduna uygun datanın oluşması. Aksi takdirde istediğimiz test senaryonu gerçekleştiremeyiz.

Aşağıdaki bazı komutlar ile temel anlamda kullanımları görebiliriz.



Person person = Instancio.create(Person.class);

Person personWithoutAgeAndAddress = Instancio.of(personModel)
    .ignore(field(Person::getAddress))
    .create();

List<Person> list = Instancio.createList(Person.class);

List<Person> list = Instancio.ofList(Person.class).size(10).create();

Person person = Instancio.createBlank(Person.class);

// Output:
// Person[name=null, address=Address[street=null, city=null, country=null]]

Person person = Instancio.ofBlank(Person.class)
    .set(field(Address::getCountry), "Canada")
    .create();

// Output:
// Person[name=null, address=Address[street=null, city=null, country=Canada]]

Person person = Instancio.create(Person.class);

Person personWithoutAgeAndAddress = Instancio.of(personModel)

.ignore(field(Person::getAddress))

.create();

List<Person> list = Instancio.createList(Person.class);

List<Person> list = Instancio.ofList(Person.class).size(10).create();

Person person = Instancio.createBlank(Person.class);

// Output:

// Person[name=null, address=Address[street=null, city=null, country=null]]

Person person = Instancio.ofBlank(Person.class)

.set(field(Address::getCountry), "Canada")

.create();

// Output:

// Person[name=null, address=Address[street=null, city=null, country=Canada]]

JUnit 5 kullanıyorsanıza aşağıdaki dependency yeterli olacaktır.



&lt;dependency&gt;
    &lt;groupId&gt;org.instancio&lt;/groupId&gt;
    &lt;artifactId&gt;instancio-junit&lt;/artifactId&gt;
    &lt;version&gt;4.7.0&lt;/version&gt;
    &lt;scope&gt;test&lt;/scope&gt;
&lt;/dependency&gt;

<groupId>org.instancio</groupId>

<artifactId>instancio-junit</artifactId>

</dependency>

JUnit 4 için ise aşağıdaki yeterlidir.



<dependency>
    <groupId>org.instancio</groupId>
    <artifactId>instancio-core</artifactId>
    <version>4.7.0</version>
    <scope>test</scope>
</dependency>

<groupId>org.instancio</groupId>

<artifactId>instancio-core</artifactId>

</dependency>

Aşağıdaki controller için test yazmayı deneyelim.



@AllArgsConstructor
@RestController
@RequestMapping("/api/v1/customers")
public class CustomerController {

    private final CustomerService customerService;

    @PostMapping
    public void save(@RequestBody CustomerSaveRequest request) {
        customerService.save(request);
    }

    @GetMapping
    public List<Customer> getAll() {
        return customerService.getCustomerList();
    }
}

@AllArgsConstructor

@RestController

@RequestMapping("/api/v1/customers")

public class CustomerController {

private final CustomerService customerService;

@PostMapping

public void save(@RequestBody CustomerSaveRequest request) {

customerService.save(request);

}

@GetMapping

public List<Customer> getAll() {

return customerService.getCustomerList();

}

Unit Test



import com.fasterxml.jackson.databind.ObjectMapper;
import com.patika.kitapyurdumcustomerservice.dto.request.CustomerSaveRequest;
import com.patika.kitapyurdumcustomerservice.service.CustomerService;
import jakarta.ws.rs.core.MediaType;
import org.instancio.Instancio;
import org.junit.jupiter.api.Test;
import org.mockito.Mockito;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.test.web.servlet.MockMvc;

import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@WebMvcTest(CustomerController.class)
class CustomerControllerTest {

    @Autowired
    private MockMvc mockMvc;

    @MockBean
    private CustomerService customerService;

    @Test
    void save() throws Exception {

        ObjectMapper mapper = new ObjectMapper();

        String body = mapper.writeValueAsString(Instancio.create(CustomerSaveRequest.class));

        mockMvc.perform(post("/api/v1/customers")
                        .content(body)
                        .contentType(MediaType.APPLICATION_JSON))
                .andExpect(status().isOk());

        verify(customerService, times(1)).save(Mockito.any(CustomerSaveRequest.class));
    }

    @Test
    void getAll() throws Exception {

        mockMvc.perform(get("/api/v1/customers")
                        .contentType(MediaType.APPLICATION_JSON))
                .andExpect(status().isOk());

        verify(customerService, times(1)).getCustomerList();

    }

}

import com.fasterxml.jackson.databind.ObjectMapper;

import com.patika.kitapyurdumcustomerservice.dto.request.CustomerSaveRequest;

import com.patika.kitapyurdumcustomerservice.service.CustomerService;

import jakarta.ws.rs.core.MediaType;

import org.instancio.Instancio;

import org.junit.jupiter.api.Test;

import org.mockito.Mockito;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;

import org.springframework.boot.test.mock.mockito.MockBean;

import org.springframework.test.web.servlet.MockMvc;

import static org.mockito.Mockito.times;

import static org.mockito.Mockito.verify;

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;

import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

@WebMvcTest(CustomerController.class)

class CustomerControllerTest {

@Autowired

private MockMvc mockMvc;

@MockBean

private CustomerService customerService;

@Test

void save() throws Exception {

ObjectMapper mapper = new ObjectMapper();

String body = mapper.writeValueAsString(Instancio.create(CustomerSaveRequest.class));

mockMvc.perform(post("/api/v1/customers")

.content(body)

.contentType(MediaType.APPLICATION_JSON))

.andExpect(status().isOk());

verify(customerService, times(1)).save(Mockito.any(CustomerSaveRequest.class));

}

@Test

void getAll() throws Exception {

mockMvc.perform(get("/api/v1/customers")

.contentType(MediaType.APPLICATION_JSON))

.andExpect(status().isOk());

verify(customerService, times(1)).getCustomerList();

}

Aşağıdaki service class’ı için de test yazmayı deneyelim.



@Service
@RequiredArgsConstructor
@Slf4j
public class CustomerService {

    private final CustomerRepository customerRepository; 

    public void save(CustomerSaveRequest request) {

        Optional<Customer> foundCustomer = customerRepository.findByEmail(request.getEmail());

        if (foundCustomer.isPresent()) {
            log.error(ExceptionMessages.EMAIL_ALREADY_EXIST);
            throw new KitapYurdumException(ExceptionMessages.EMAIL_ALREADY_EXIST);
        }

        Customer customer = CustomerConverter.toCustomer(request);

        customerRepository.save(customer);

        log.info("customer created. {}", customer.getEmail());
    }
}

@Service

@RequiredArgsConstructor

@Slf4j

public class CustomerService {

private final CustomerRepository customerRepository;

public void save(CustomerSaveRequest request) {

Optional<Customer> foundCustomer = customerRepository.findByEmail(request.getEmail());

if (foundCustomer.isPresent()) {

log.error(ExceptionMessages.EMAIL_ALREADY_EXIST);

throw new KitapYurdumException(ExceptionMessages.EMAIL_ALREADY_EXIST);

}

Customer customer = CustomerConverter.toCustomer(request);

customerRepository.save(customer);

log.info("customer created. {}", customer.getEmail());

}

Unit Test

Bir çok durumda test verisi oluşturmak uğraştırıcı ve sıkıcı olabiliyor.Eğer özel bir veriye ihtiyacımız varsa Instancio bunun bir için de çözüm sunuyor.

Set



package com.patika.kitapyurdumcustomerservice.service;

import com.patika.kitapyurdumcustomerservice.dto.request.CustomerSaveRequest;
import com.patika.kitapyurdumcustomerservice.exception.ExceptionMessages;
import com.patika.kitapyurdumcustomerservice.exception.KitapYurdumException;
import com.patika.kitapyurdumcustomerservice.model.AccountType;
import com.patika.kitapyurdumcustomerservice.model.Customer;
import com.patika.kitapyurdumcustomerservice.repository.CustomerRepository;
import org.instancio.Instancio;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.Mockito;
import org.mockito.junit.jupiter.MockitoExtension;

import java.util.Optional;

import static org.assertj.core.api.Assertions.assertThat;
import static org.instancio.Select.field;
import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.mockito.Mockito.*;

@ExtendWith(MockitoExtension.class)
class CustomerServiceTest {

    @InjectMocks
    private CustomerService customerService;

    @Mock
    private CustomerRepository customerRepository;

    @Test
    void shouldThrowException_whenUserAlreadyExist() {

        String email = "bilisimio@gmail.com";

        //given
        CustomerSaveRequest request = Instancio.of(CustomerSaveRequest.class)
                .set(field(CustomerSaveRequest::getEmail), email)
                .set(field(CustomerSaveRequest::getName), "bilisimio")
                .create();

        Mockito.when(customerRepository.findByEmail(email))
                .thenReturn(Optional.of(Instancio.of(Customer.class)
                        .set(field(Customer::getEmail), email)
                        .set(field(Customer::getIsActive), false)
                        .set(field(Customer::getAccountType), AccountType.PLATINUM)
                        .create()));

        //when
        KitapYurdumException exception = assertThrows(KitapYurdumException.class, () -> customerService.save(request));

        //then
        assertThat(exception).hasMessage(ExceptionMessages.EMAIL_ALREADY_EXIST);
        verifyNoMoreInteractions(customerRepository);
    }
}

package com.patika.kitapyurdumcustomerservice.service;

import com.patika.kitapyurdumcustomerservice.dto.request.CustomerSaveRequest;

import com.patika.kitapyurdumcustomerservice.exception.ExceptionMessages;

import com.patika.kitapyurdumcustomerservice.exception.KitapYurdumException;

import com.patika.kitapyurdumcustomerservice.model.AccountType;

import com.patika.kitapyurdumcustomerservice.model.Customer;

import com.patika.kitapyurdumcustomerservice.repository.CustomerRepository;

import org.instancio.Instancio;

import org.junit.jupiter.api.Test;

import org.junit.jupiter.api.extension.ExtendWith;

import org.mockito.InjectMocks;

import org.mockito.Mock;

import org.mockito.Mockito;

import org.mockito.junit.jupiter.MockitoExtension;

import java.util.Optional;

import static org.assertj.core.api.Assertions.assertThat;

import static org.instancio.Select.field;

import static org.junit.jupiter.api.Assertions.assertThrows;

import static org.mockito.Mockito.*;

@ExtendWith(MockitoExtension.class)

class CustomerServiceTest {

@InjectMocks

private CustomerService customerService;

@Mock

private CustomerRepository customerRepository;

@Test

void shouldThrowException_whenUserAlreadyExist() {

String email = "[email protected]";

//given

CustomerSaveRequest request = Instancio.of(CustomerSaveRequest.class)

.set(field(CustomerSaveRequest::getEmail), email)

.set(field(CustomerSaveRequest::getName), "bilisimio")

.create();

Mockito.when(customerRepository.findByEmail(email))

.thenReturn(Optional.of(Instancio.of(Customer.class)

.set(field(Customer::getEmail), email)

.set(field(Customer::getIsActive), false)

.set(field(Customer::getAccountType), AccountType.PLATINUM)

.create()));

//when

KitapYurdumException exception = assertThrows(KitapYurdumException.class, () -> customerService.save(request));

//then

assertThat(exception).hasMessage(ExceptionMessages.EMAIL_ALREADY_EXIST);

verifyNoMoreInteractions(customerRepository);

}

Supply

supply methodu ile verdiğimiz veri tipine göre istediğimiz veriyi atayabiliriz.



 CustomerSaveRequest request = Instancio.of(CustomerSaveRequest.class)
                .set(field(CustomerSaveRequest::getEmail), email)
                .set(field(CustomerSaveRequest::getName), "bilisimio")
                .supply(all(LocalDate.class), () -> LocalDate.now()) // <strong>bütün</strong> <strong>LocalDate'lere</strong> istediğimiz değeri atayabiliriz
                .create();

CustomerSaveRequest request = Instancio.of(CustomerSaveRequest.class)

.set(field(CustomerSaveRequest::getEmail), email)

.set(field(CustomerSaveRequest::getName), "bilisimio")

.supply(all(LocalDate.class), () -> LocalDate.now()) // <strong>bütün</strong> <strong>LocalDate'lere</strong> istediğimiz değeri atayabiliriz

.create();

withNullable

Yine senaryo gereği bazı değişkenlerimiz null olabiliyor ve bu durum için de withNullable methodu kullanabiliriz.



 CustomerSaveRequest request = Instancio.of(CustomerSaveRequest.class)
                .set(field(CustomerSaveRequest::getEmail), email)
                .set(field(CustomerSaveRequest::getName), "bilisimio")
                .supply(all(LocalDate.class), () -> LocalDate.now()) // bütün LocalDate'lere istediğimiz değeri veriyoruz
                .withNullable(field(CustomerSaveRequest::getSurname))
                .withNullable(field(CustomerSaveRequest::getProvince))
                .create();

CustomerSaveRequest request = Instancio.of(CustomerSaveRequest.class)

.set(field(CustomerSaveRequest::getEmail), email)

.set(field(CustomerSaveRequest::getName), "bilisimio")

.supply(all(LocalDate.class), () -> LocalDate.now()) // bütün LocalDate'lere istediğimiz değeri veriyoruz

.withNullable(field(CustomerSaveRequest::getSurname))

.withNullable(field(CustomerSaveRequest::getProvince))

.create();

Genel olarak kendi kullandığım methodları örneklemeye çalıştım. Daha fazlası için kendi sayfasına bakabilirsiniz.

https://www.instancio.org/user-guide/#creating-objects

Faydalı olması dileğiyle.