hello channel I am working on a Kotlin + Spring application, and wondering if this is possible or not: there is a properties configuration:

@ConfigurationProperties("application.custom.properties")
data class SomeProperties(
    val foo: Long,
    val bar: String,
)

application.properties:

application.custom.properties.foo=1
application.custom.properties.bar=Text Here

ok, so I have another class, just a POJO, and need to get the values from that configuration properties bean

data class ObjectBuilder(
    var fooValue: Long = SomeProperties.foo,
    var barValue: String = SomeProperties.bar,
)

is there a way of getting the SomeProperties values on a non spring context?

If somebody want to experiment on a more efficient Kotlin support in Spring framework, open to get some help with an experimental Spring Framework branch that uses

kotlinx.metadata.jvm

instead of

kotlin-reflect

and

jackson-module-kogera

to get some data points on before/after https://github.com/spring-projects/spring-framework/issues/21546#issuecomment-1384418132

Hi team. please: is it possible to disable Kafka during my unit tests? I’ve created a class with a method using

@KafkaListener

annotation and when I run the functional tests, I produce a protobuf topic message and the listener works properly to consume that message. But my unit test need to test this method, and I am using this:

@Autowired
lateinit var ingestionListener: IngestionConsumerListener

to inject my listener and I want to test this method but without the Kafka in memory. But the test is trying to load the Kafka because I am getting this:

Could not resolve placeholder 'ingestion.config.topic.name' in value "#{'${ingestion.config.topic.name}'}"

that is used in my implementation:

@KafkaListener(
    id = "ingestionListener",
    topics = ["#{'\${ingestion.config.topic.name}'}"],
    groupId = "#{'\${ingestion.consumer.group.id}'}",
    concurrency = "#{'\${ingestion.config.consumer.concurrency}'}"
)
fun consumeIngestion(ingestionHttpRequest: ConsumerRecord<String, IngestionHttpRequest.HttpRequest>)

I am trying to use this kind of solution for my first unit test using Kotlin and Kafka:

@EnableAutoConfiguration(exclude = [KafkaAutoConfiguration::class])

but I am still struggling with the error above… Please any suggestion to fix that? How to test a kafka listener using Java/Kotlin without Kafka in memory? Issue: FIXED! I only needed to add all properties necessary for the UT and Kafka is not necessary at memory

Hi chat! i need help! please I have a class

data class EmailVerificationStateRequestDto (
    @field:NotBlank(message = "parameterName не указан")
    @field:Size(min = 6, max = 6, message = "parameterName должен содержать 6 алфавитно-цифровых символов" )
    @field:Pattern(regexp = "^[a-zA-Z0-9]+\$")
    val parameterName: String?,
    val email: String?
)

three validation for one field and i have this class where i can get some information about error p.s. service vy webFlux, Mono, Flux, Reactive

@ExceptionHandler(WebExchangeBindException::class)
fun handleException(bindException: WebExchangeBindException): ResponseEntity<String> {
    val validationError = ValidationError(
        bindException.fieldError?.defaultMessage
            ?: throw RuntimeException("Something wrong with validation error message")
    )
    return ResponseEntity.badRequest().body(objectMapper.writeValueAsString(validationError))
}

when i call controller method and set parameterName = “” i got 3 errors, i want get 1 error NotBlank only, not all 3 validations, how can i do this?

Hi folks, anyone getting the error:

No accessor to set property @org.springframework.data.annotation.Id() @org.springframework.data.relational.core.mapping.Column(value="id")private final int org.msensis.imahub.hub.core.internal.entities.MessageEntity.id
java.lang.UnsupportedOperationException: No accessor to set property @org.springframework.data.annotation.Id() @org.springframework.data.relational.core.mapping.Column(value="id")private final int org.msensis.imahub.hub.core.internal.entities.MessageEntity.id

While using data classes for entities? Thanks in advance for any answers

There is a need to distribute a jar to clients. However, there will be future releases of the jar. As such are there any good autoupdate software for future jar releases to the clients?

cross posting -> https://kotlinlang.slack.com/archives/C7A1U5PTM/p1674698607791439

virtual meeting Hi everyone! Join the livestream on February 14. https://kotlinlang.slack.com/archives/C0BJ0GTE2/p1675674970068069

Hey guys! I'm new to server development with spring and I was wondering if there are any helpful resources out there specifically for Kotlin language (most I've seen are for Java language). Please I'd really appreciate any pointers. Thanks

In Spring, instead of creating functions that create fake responses, is there something like what they call “factories” (in other frameworks) that can create responses with the Faker librairie ? Something like this: https://docs.adonisjs.com/guides/models/factories ?

When using webflux restcontroller, will it beneficial using coroutines suspend functions for the controllers, given that webflux is non-blocking in nature?

In my project , I got a wired issue.

// trigger a scheduled task to parse cvs
// aList is parsed from a cvs file.
aList.forEach{
    // use it.refId to query extra record from our database.
    val extra = repository.findByRefId(it.refId)
    if(it.status == 'error'{ 
        //do some update on extra by it.status condition
        extra.status = 'error'
        repository.save(extra) // A kotlin coroutines repository
    }
}

// in the last scheduled task, only one status(error) is needed to updated
// but finally after the iteration, all records are updated the error status

Hey I am new to Spring and coming from Android I wonder if Spring

Service

is equivalent of

UseCase

(Clean Architecture)?

anyone have experience using PlanetScale with Spring Boot

what are people using to validate password requirements?

Consider such code:

data class Task(val name: String, val description: String)

class CreateTeskUseCase(val repository: Repository) {
    fun execute(taskRequestModel: TaskRequestModel) {
        val task = Task(taskRequestModel.name, taskRequestModel.description)
        //...
        repository.save(task)
    }
}

This works fine, but when I want to test interaction with the repo the "dummy" factory is required to get testable

Task

instance:

class CreateTeskUseCase(val repository: Repository, val taskFactory: TaskFactory) {
    fun execute(taskRequestModel: TaskRequestModel) {
        val task = taskFactory.create(taskRequestModel.name, taskRequestModel.description)
        //...
        repository.save(task)
    }
}

class TaskFactory {
    fun create(name: String, description: String) = Task(name, description)
}

I wonder if there is a way to generate this

TaskFactory

class (perhaps using

ksp

). Something like this

@GenerateFactory

annotation?

@GenerateFactory
data class Task(val name: String, val description: String)

InteliJ IDEA presents

Could not autowire No beans of "TaskRepository" found

warning in the

UpdateTaskDescriptionUseCase

class (attached image): Here is repo class:

@Repository
class TaskRepository {
    // ...
}

The warning seems to be a false positive because the above code works fine (the repo class is injected into the use case) I wonder whats the desired solution is here. Do I need another annotation together with the repo annotation?

Is there a convenient way to make

@Component

annotations work with kotlin objects and automatically make that bean a singleton? I typically create a wrapper class to annotate as

@Component

to wrap my kotlin objects.

Hi, is it possible to use

Scheduled

annotation with suspend function without wrapping it to a runBlocking block?

Hey quick off topic question - I am learning Spring and I wonder what is the best place to ask spring specific questions?

set the channel topic: Discussions on Kotlin specific integration with Spring, not Spring in general. For Spring-generic questions, try Gitter: https://gitter.im/spring-projects/spring-boot. Spring Boot Kotlin guides: https://spring.io/guides/tutorials/spring-boot-kotlin/

Hi Channel! I don’t know if this is the right place as my question is related to AWS dynamodb with the V2 enhanced client (of course in Spring Boot + Kotlin). I’m following this blog post. I keep getting this exception from the dynamodb SDK when I try to write to dynamo -

java.lang.IllegalArgumentException: Attempt to execute an operation that requires a primary index without defining any primary key attributes in the table metadata.

. I define partition key in the data class. But it keeps complaining that I don’t have it!. Here’s the entire code:

package com.redacted.backend.monolith.app.controllers

import com.redacted.backend.monolith.config.dynamodb.createDynamoDbClient
import org.springframework.beans.factory.annotation.Value
import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration
import org.springframework.graphql.data.method.annotation.Argument
import org.springframework.graphql.data.method.annotation.MutationMapping
import org.springframework.stereotype.Controller
import org.springframework.stereotype.Repository
import software.amazon.awssdk.enhanced.dynamodb.DynamoDbEnhancedClient
import software.amazon.awssdk.enhanced.dynamodb.TableSchema
import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbBean
import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbPartitionKey
import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbSortKey

@Controller
class DogController(private val repo: DogRepository) {

    @MutationMapping
    fun createDog(@Argument dog: Dog): String {
        return repo.create(dog)
    }

}

@DynamoDbBean
data class Dog(
    @get:DynamoDbPartitionKey
    val dogId: String? = null,
    @get:DynamoDbSortKey
    val rating: Int = 0,
    val name: String? = null
)

@Configuration
class DynamoClient(
    @Value("aws.dynamodb.access-key") private val dynamoDbAccessKey: String,
    @Value("aws.dynamodb.secret-key") private val dynamoDbSecretKey: String,
    @Value("aws.dynamodb.region") private val dynamoDbRegion: String
) {

    @Bean
    fun dynamoDbClient(): DynamoDbEnhancedClient = createDynamoDbClient(
        accessKey = dynamoDbAccessKey,
        secretKey = dynamoDbSecretKey,
        region = dynamoDbRegion
    )

}

@Repository
class DogRepository(private var client: DynamoDbEnhancedClient) {

    private val table = client.table("dog_table", TableSchema.fromBean(Dog::class.java))
    fun create(dog: Dog): String {
        table.putItem(dog)
        println("Written the dog to db successfully!")
        return "Written"
    }
}

Here’s the whole error: Any help would be very much appreciated! Error message is in the 🧵

I'd like to change incoming/outgoing representation of an enum in a spring boot app. What do I miss?

public enum class Gender(@JsonValue val value: String) {
    MALE("m"), FEMALE("f");
}

The controller:

@GetMapping("/test", produces = [org.springframework.http.MediaType.APPLICATION_JSON_VALUE])
    fun gender(@RequestParam gender: Gender): Map<String, Gender> =
        when (gender) {
            Gender.MALE -> mapOf("result" to Gender.FEMALE)
            Gender.FEMALE -> mapOf("result" to Gender.MALE)
        }

For

GET localhost:8080/test?gender=m

I expect to get

{"result": "f"}

.

What's the simplest way to run a spring boot kotlin app inside docker? My attempt does not work, it freezes 😞

docker run --user $(id -u) --volume "$PWD":/home/gradle/project --workdir /home/gradle/project gradle:7-jdk17 gradle --no-daemon --no-rebuild --no-scan --no-watch-fs --no-parallel bootRun

(to which channel does this question fit?)

Hey folks, I'm trying to register a Kotlin top-level

object

as a bean in Spring and am wondering if there's a simpler way to do this. Why I'm doing this is a long story. What I've tried so far: 1. Annotate my object with

@Component

(results in Spring creating a second instance of my object) 2. Create a separate

@Configuration

class and expose my object as an

@Bean

in a method in there.

How can I configure Spring Webflux to use Kotlinx Serialization over Jackson, even though both are on classpath? I can't exclude Jackson completely due to using libs which depend on it.

Hello, I’m trying to use Micrometer Tracing in Spring Boot 3.0 with Kotlin, but I think it’s not working the way I expected. From what I read, I thought that tracing information stored in coroutines contexts would flow through the different Threads of execution. But it looks like that once the thread changes, trace information is lost. I’ve created this simple controller to test this:

@RestController
class TestController(val tracer: Tracer) {
    private val logger: Logger = LoggerFactory.getLogger(this::class.java)

    @GetMapping("/test")
    suspend fun test() {
        <http://logger.info|logger.info>("before: ${tracer.currentTraceContext().context()?.traceId()}")
        delay(50)
        <http://logger.info|logger.info>("after: ${tracer.currentTraceContext().context()?.traceId()}")
    }
}

The second log statement reports a null value for the traceId, because the Kotlin

delay

function caused a thread switch and the trace informations is lost, Can anyone help here? Why is this happening? Is it by design? Is there something I can do to guarantee that the traceId is always present?

Has anyone ever tried to run a spring boot app without the

org.jetbrains.kotlin.plugin.spring

plugin? My understanding is that the beans DSL removes some proxying so it might not require open classes? But I'm stuck at

@SpringBootApplication

because I haven't found a non-annotated equivalent.