I have a multi module SpringBoot app with gradle and kotlin, trying spring-data-r2dbc. If i use #Repository annotation over my Repository class, #Autowired DatabaseClient is null. But if i change annotation to #Component, #Autowired works and I do successfull call to database. Any idea why #Autowire isn't working with #Repository annotation?
Database configuration class:
#Configuration
open class DatabaseConfiguration(
#Value("\${spring.data.mssql.host}") private val host: String,
// #Value("\${spring.data.mssql.port}") private val port: Int,
#Value("\${spring.data.mssql.database}") private val database: String,
#Value("\${spring.data.mssql.username}") private val username: String,
#Value("\${spring.data.mssql.password}") private val password: String)
: AbstractR2dbcConfiguration() {
#Bean
override fun connectionFactory(): ConnectionFactory {
return MssqlConnectionFactory(
MssqlConnectionConfiguration.builder()
.host(host)
//.port(port)
.database(database)
.username(username)
.password(password).build()
)
}
}
Main class:
#SpringBootApplication
#EnableR2dbcRepositories
class MultigradleApplication
Repository class (in module "data"):
#Repository
open class TestRepo() {
#Autowired
lateinit var client: DatabaseClient
fun getAll() : Flux<PersonDTO> {
return client.execute("SELECT * FROM Person.Person")
.`as`(PersonDTO::class.java)
.fetch()
.all()
}
}
The problem was that I injected PersonService as its IPersonService interface into my Controller, but I didn't have an interface for TestRepo and injected it directly. When I added ITestRepo interface to TestRepo and injected it into the service as ITestRepo, everything started working.
Related
Let me show what I mean by code.
Interface:
interface MyInterface {
}
I have 2 implementation classes:
#Singleton
class Implementation1 #Inject constructor(
private val gson: Gson,
) : MyInterface {
}
#Singleton
class Implementation2 #Inject constructor(
#ApplicationContext private val context: Context,
) : MyInterface {
}
I need a repository class with list of implementations of MyInterface:
#Singleton
class MyRepository #Inject constructor(
private val implementations: List<MyInterface>,
) {
}
Problem part: I am trying to inject as below:
#InstallIn(SingletonComponent::class)
#Module
object MyDiModule {
#Provides
fun providesImplementations(
imp1: Implementation1,
imp2: Implementation2,
): List<MyInterface> {
return listOf(imp1, imp2)
}
}
But I get compilation error:
/home/sayantan/AndroidStudioProjects/example/app/build/generated/hilt/component_sources/debug/com/example/ExampleApplication_HiltComponents.java:188: error: [Dagger/MissingBinding] java.util.List<? extends com.example.MyInterface> cannot be provided without an #Provides-annotated method.
public abstract static class SingletonC implements FragmentGetContextFix.FragmentGetContextFixEntryPoint,
^
Any way to achieve this?
This might be late but would like to drop my thoughts.
Firstly, you need to annotate your #Provides methods in the module class because dagger would certainly throw an error of multiple bindings of MyInterface.
For example:
enum class ImplType {
Impl1, Impl2
}
#Qualifier
#Retention(AnnotationRetention.RUNTIME)
annotation class ImplTypeAnnotation(val type: ImplType)
#Singleton
#Provides
#ImplTypeAnnotation(ImplType.Impl1)
fun provideImplementation1(impl1: Implementation1): MyInterface
// Do the same for Implementation2
Secondly, once these are done, you need to individually inject them into the Repository class. e.g.
class MyRepository #Inject constructor(
#ImplTypeAnnotation(ImplType.Impl1) private val implementation1: MyInterface,
#ImplTypeAnnotation(ImplType.Impl2) private val implementation2: MyInterface
) {
// get the implementations as list here using Kotlin listOf()
}
NB: I'm not sure if providing List<MyInterface> would work.
Hope this helps!
I do not know how correct this answer is, but it works for me, so posting as answer.
This can be done using the annotation #JvmSuppressWildcards.
In the above example, everything is fine, I just need to add this annotation to the class where the dependencies are being injected, i.e. the MyRepository class.
#JvmSuppressWildcards
#Singleton
class MyRepository #Inject constructor(
private val implementations: List<MyInterface>,
) {
}
I was seeing the same problem in the project I've been working on, but moving from List<> to Array<> seemed to fix it for me.
So in your case the hilt injection would look like:
#Provides
fun providesImplementations(
imp1: Implementation1,
imp2: Implementation2,
): Array<MyInterface> {
return arrayOf(imp1, imp2)
}
Then used with:
#Singleton
class MyRepository #Inject constructor(
private val implementations: Array<MyInterface>,
) {
}
I'm writing tests for my Controller class. I have configuration class which looks like this :
#Configuration
#Import(RoomRepository.class)
public class TestConfig {
#MockBean
RoomRepository roomRepository;
#Bean
ReservationService reservationService() {
return new ReservationService(roomRepository);
}
}
In controller test class I'm injecting config class :
#WebMvcTest(ReservationController.class)
#Import({TestConfig.class})
class ReservationControllerTest { ... }
Everything works well except one thing. I need "real" room repository - not mock. When I try to #Autowired that repository I'm receiving an error that it's interface, not class (which is quite obvious). How can I initialize working instance of RoomRepository ?
You can do it like this:
private RoomRepository roomRepository;
#Autowired
public YourClassName(RoomRepository roomRepository){
this.roomRepository = roomRepository
}
I am trying to write unit tests for a Spring boot service using JUnit 4 and Mockito.
I used constructor based dependency injection for my service, The Signature is:
class VbServiceImp(val jdbcTemplate: NamedParameterJdbcTemplate,
val nuanceService: NuanceService,
val conf: AppConfigProps,
val eventService: EventServiceImp,
val audioTrimService: AudioTrimServiceIF,
val vbNuanceStagingDeletionsService: VbNuanceStagingDeletionsService) : VbService {...}
in another part of the application This service gets injected into a controller and somehow spring just magically knows what to inject without me specifying this (Any idea how this works/explanation would be appreciated, guess it's based on component scan?)
example:
class VbController(val vbService: VbService) {...}
Now in my VBServiceImpl Unit test class I try to mock all the above dependencies before declaring vBService in order to manually inject all dependencies into VBService during declaration.
the relevant part of my test class looks like this:
#RunWith(SpringRunner::class)
#ContextConfiguration()
class VBServiceTests {
#MockBean
val jdbcTemplate: NamedParameterJdbcTemplate = mock()
#MockBean
val nuanceService: NuanceService = mock()
#MockBean
val appconfigProps: AppConfigProps = AppConfigProps()
#MockBean
val eventService: EventServiceImp = mock()
#MockBean
val audioTrimService: AudioTrimService = mock()
#MockBean
val vbNuanceStagingDeletionsService: VbNuanceStagingDeletionsService = mock()
val vbService: VbServiceImp = VbServiceImp(jdbcTemplate, nuanceService, appconfigProps, eventService, audioTrimService, vbNuanceStagingDeletionsService)
#SpyBean
val vbServiceSpy: VbServiceImp = Mockito.spy(vbService)
#Before
fun setup() {
initMocks(this)
}
When I run a test I get the exception below. If I understand this correctly there is already a bean of type jdbcTemplate in the application context and therefore I can't define the #Mockbean jdbcTemplate above?
exception:
private final org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate com.cc.ff.vb.service.VBServiceTests.jdbcTemplate cannot have an existing value
So now the issue is: If I removed the #MockBean jdbcTemplate variable then I can't inject jdbcTemplate when I declare vbService in my test class. So how could I get around this/make this work?
Just to check I removed the jdbcTemplate parameter from the vbService class constructor and changed it to a #Autowired field injected class variable and provided the mock class using #TestConfig. This worked however then the exception popped up on the next constructor parameter (NuanceService)
i'm out of ideas and google hasn't returned anything of value. Do I remove all constructor injected dependencies and then make them field injected using #Autowired and then provide the beans in the nested #TestConfig annotated class or is there a better/cleaner way? AFAIK field based injection is supposed to be bad practice?
example of providing correct bean for testing #Autowired field injected jdbcTemplate variable:
#TestConfiguration
class testConfig {
#Bean
fun jdbcTemplate(): NamedParameterJdbcTemplate {
return mock<NamedParameterJdbcTemplate>()
}
}
This is how I ended up making it work:
#TestConfiguration
class testConfig {
#Bean
fun jdbcTemplate(): NamedParameterJdbcTemplate {
return mock<NamedParameterJdbcTemplate>()
}
#Bean
fun nuanceService(): NuanceService {
return mock<NuanceService>()
}
#Bean
fun appConfigProps(): AppConfigProps {
return mock<AppConfigProps>()
}
#Bean
fun eventService(): EventServiceImp {
return mock<EventServiceImp>()
}
#Bean
fun audioTrimService(): AudioTrimService {
return mock<AudioTrimService>()
}
#Bean
fun vbNuanceStagingDeletionService(): VbNuanceStagingDeletionsService {
return mock<VbNuanceStagingDeletionsService>()
}
}
#MockBean
lateinit var nuanceService: NuanceService
#SpyBean
lateinit var vbServiceSpy: VbServiceImp
I'm still not sure if this is the best/optimal way of going about this so would appreciate some more details...
I have working kotlin service, but when i try to write test for it i get stuck because i cant get all my services initialized no matter what...
#RunWith(SpringRunner::class)
class DataServiceTest {
#InjectMocks
private lateinit var DataService : DataService
#Mock
private lateinit var updateDataService: UpdateDataService
#Test
fun shouldUpdateCustomerEmail() {
DataService.setNewCustomerEmail("221722", ApiEmail("test#test.org"))
}
}
which calls DataService class:
#Autowired
private lateinit var updateDataService: UpdateDataService
.....
fun setNewCustomerEmail(id: String, email: ApiEmail) {
updateDataService.setNewCustomerEmail(id, email)
}
which calls UpdateDataService class:
#Service
open class UpdateDataService {
#Autowired
private lateinit var addressRepository: AddressRepository
fun setNewCustomerEmail(id: String, email: ApiEmail) {
val AddressList = getCustomerAddressList(id)
mapNewEmailToAddressList(AddressList, email)
cusAddressRepository.saveAll(AddressList)
}
fun getCustomerCusbaAddressList(id: String) : List<Address> {
return addressRepository.findAddressByCustomerId( id )
}
fun mapNewEmailToAddressList(cusbaAddressList : List<Address>, email: ApiEmail) {
AddressList.map { DataUtil.trimAddressFields( it ) }
AddressList.map { it.email = email.email }
}
}
I've tried lots of different #RunWith() properties and lots of different ways to Autowire / Mock / InjectMocks but to no avail.
Problem:
At the moment with this code. AddressRepository will be uninitialized when test gets to UpdateDataService.class in line. return addressRepository.findAddressByCustomerId( id )
Question:
How do i wire all these services in such way that services are loaded when app is running, but also test would know how to wire these services and repository ?
Using Spring Boot Test you can operate context easily
#RunWith(SpringRunner::class)
#SpringBootTest
class DataServiceTest
or provide a #TestConfiguration
Is it possible to do something like following in Kotlin?
#Autowired
internal var mongoTemplate: MongoTemplate
#Autowired
internal var solrClient: SolrClient
Recommended approach to do Dependency Injection in Spring is constructor injection:
#Component
class YourBean(
private val mongoTemplate: MongoTemplate,
private val solrClient: SolrClient
) {
// code
}
Prior to Spring 4.3 constructor should be explicitly annotated with Autowired:
#Component
class YourBean #Autowired constructor(
private val mongoTemplate: MongoTemplate,
private val solrClient: SolrClient
) {
// code
}
In rare cases, you might like to use field injection, and you can do it with the help of lateinit:
#Component
class YourBean {
#Autowired
private lateinit var mongoTemplate: MongoTemplate
#Autowired
private lateinit var solrClient: SolrClient
}
Constructor injection checks all dependencies at bean creation time and all injected fields is val, at other hand lateinit injected fields can be only var, and have little runtime overhead. And to test class with constructor, you don't need reflection.
Links:
Documentation on lateinit
Documentation on constructors
Developing Spring Boot applications with Kotlin
Yes, java annotations are supported in Kotlin mostly as in Java.
One gotcha is annotations on the primary constructor requires the explicit 'constructor' keyword:
From https://kotlinlang.org/docs/reference/annotations.html
If you need to annotate the primary constructor of a class, you need to add the constructor keyword to the constructor declaration, and add the annotations before it:
class Foo #Inject constructor(dependency: MyDependency) {
// ...
}
You can also autowire dependencies through the constructor. Remember to annotate your dependencies with #Configuration, #Component, #Service etc
import org.springframework.stereotype.Component
#Component
class Foo (private val dependency: MyDependency) {
//...
}
like that
#Component class Girl( #Autowired var outfit: Outfit)
If you want property injection but don't like lateinit var, here is my solution using property delegate:
private lateinit var ctx: ApplicationContext
#Component
private class CtxVarConfigurer : ApplicationContextAware {
override fun setApplicationContext(context: ApplicationContext) {
ctx = context
}
}
inline fun <reified T : Any> autowired(name: String? = null) = Autowired(T::class.java, name)
class Autowired<T : Any>(private val javaType: Class<T>, private val name: String?) {
private val value by lazy {
if (name == null) {
ctx.getBean(javaType)
} else {
ctx.getBean(name, javaType)
}
}
operator fun getValue(thisRef: Any?, property: KProperty<*>): T = value
}
Then you can use the much better by delegate syntax:
#Service
class MyService {
private val serviceToBeInjected: ServiceA by autowired()
private val ambiguousBean: AmbiguousService by autowired("qualifier")
}