If I want to use Spring retry in Java I do this, with "@BackOff". If I paste the same annotation on a Kotlin function it complains about the @ sign with "an annotation can't be used as the annotations argument, so I have to remove the @ sign which is what also happens if I convert the Java to Kotlin Why is this and will the Kotlin work without the @ sign ? Kotlin:

@Retryable(backoff = @Backoff(delay = 2222)) // won't compile
    fun doIt() {
    }

Java:

public class Delme {

    @Retryable(backoff = @Backoff(delay = 2222))
    void doIt() {

    }
}

This isn't specific to Kotlin but maybe someone knows. I cannot get spring to bind a query string to a nested object when using WebFlux. An example I threw together:

@GetMapping("/api/users")
fun getAll(user: User) = Mono.just(user)
-- snip --

data class User(
    val firstName: String,
    val address: Address
)

data class Address(
    val street: String
)

Curl:

curl '<http://localhost:8080/api/users?firstName=shawn&address.street=foo>'

500 error:

org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.expediagroup.application.User]: Constructor threw exception; nested exception is java.lang.IllegalArgumentException: Parameter specified as non-null is null: method com.expediagroup.application.User.<init>, parameter address

I am pretty sure this works with the servlet API.

I think you need

fun getAll(@RequestBody @Validated user: User).....

Can anyone help explain why my validation isn't working?

data class Credential(
        @field:JsonProperty("country_code")
        @field:Pattern(regexp = "^[A-Z]{2}$", message = "country_code must be a string of 2 capital letters i.e. DE")
        val countryCode: String? = null,
)

With

fun registerCredentials(@Validated @RequestBody credential: Credential):Credential{ 
   //...
}

I've tried

@Valid

and that doesn't work either. I don't get any error, I just ged a object with null values.

I would like to bootstrap my Spring application/context in tests programatically (not via SprintTest JUnit annotation) - any idea how to do that? Googling is failing me 🙂 Any pointers would be appreciated.

How do you extract the body from a ResponeEntity<> with type safety? getBody() has a

object?

signature, and you can work around this with

!!

. Is this the prefered method?

Is there a way in SpringWebFlux to get current Http Request object in a class apart from the controller and webfilter. Something similar to ServerRequestContext provided by Micronaut Framework. Using that i can get hold of http request during its lifecycle.

I am trying to write integration test using @transaction annotaion. My integration test uses test containers. Whenever I remove the tranasction annotation, I am able to ser data in test containers, in docker. However if i add transaction annotation, i don't see data in mysql test container. Wondering at what point does data get commited, if tranaction annotation is used at method level in a springboot integration test?

What is the functional bean equivalent of constructor injection of a value

@Value("\${some.value:default}") someValue: String

Is it possible to use spring boot with Kotlin 1.4-M3?

hello! 👋 while working on custom

FactoryBean

I’m hitting some weird (at least to me) behavior - when I create the underlying object I need to configure it with some beans retrieved from application context (factory is application context aware). Weird part is the different behavior between retrieving bean by name (works - loads necessary autoconfigs) and the type (fails -> dependent config is not loaded).

// works - dependent auto config is loaded
val targetBean = applicationContext.getBean("targetBeanName")

// blows up with no bean
val targetBean = applicationContext.getBean(TargetBean::class.java)

Any ideas?

I have a problem with spring-data / hibernate and detached entities. This isn't particularly a kotlin-problem - but since I'm doing the whole project in kotlin, and the example code is kotlin, I'm hoping, that it is still acceptable to post this here. The gist of it is, that im calling

val adminRole = roles.findByName("admin")!!
val adminUser = BackendUser("admin", adminRole
    // some more data here
)
users.save(adminUser)

and get org.hibernate.PersistentObjectException: detached entity passed to persist: my.package.name.user.UserRole More details are in this SO post: https://stackoverflow.com/questions/62874155/spring-data-hibernate-detached-entity-passed-to-persist Any help would be appreciated.

I'm having a problem with trying to use WebClient with Kotlin. I'm just trying to make a GET request, but I keep getting

org.springframework.web.reactive.function.UnsupportedMediaTypeException: Content type 'text/html;charset=utf-8' not supported for bodyType

. Here's the service:

val client = WebClient.builder()
                .baseUrl(apiUrl)
                .defaultHeader(HttpHeaders.CONTENT_TYPE, MediaType.ALL_VALUE)
                .defaultHeader("X-API-TOKEN", apiToken)
                .build()

        return client.get()
                .uri("/$directoryId/mailinglists/$mailingListId")
                .accept(MediaType.APPLICATION_JSON, MediaType.TEXT_HTML)
                .acceptCharset(Charset.forName("UTF-8"))
                .retrieve()
                .bodyToMono(GetMailingListResponse::class.java)

Here's the controller:

@GetMapping("/directories/{directoryId}/mailinglists/{mailingListId}")
    fun handle(@PathVariable directoryId: String, @PathVariable mailingListId: String): Mono<ResponseEntity<GetMailingListResponse>> {
        val resp = service.createMailingList(directoryId, mailingListId)
        return resp.map {
            body -> ResponseEntity.ok(body)
        }
    }

Any help would be appreciated.

How can I test 2nd level cache hits in a unit test? I’m using this article as a reference https://www.baeldung.com/hibernate-second-level-cache but I’m not sure how to test it because I can’t seem to get access to the Cachemanager singleton in Kotlin

Hello. I am developing spring server with kotling using VSCode. But I have problems with auto importing in vscode. Cloud anyone help me?

Hi, i'm doing an e commerce with the backend in spring and for recipes i'm returning mimeMessage emails but i'm building my htmls as strings dynamically, so it's a hard string process ... is there any library that you've used and recommend for doing this?

Hi, does anyone know if `@schedule`annotation works with kotlin `suspended`functions?

A noob question: When using Spring’s 

@Autowired

 with Kotlin, I’m confused whether this

@Autowired
private lateinit var userService: UserService

is a field injection or a setter injection. In the documentation, the Kotlin equivalent of both field and setter injection of Java were all in this fashion. I read that field injection should be avoided, and I’ll try to stick with constructor injection if possible, but I’m just trying them out to learn. If there is actually like a more stricter equivalents, I’d like to know how to write them in Kotlin. Can anyone shed some light on this to me?

soo im using spring boot with kotlin Entity

@Entity
@Table(name="storypost")
class StoryPost(
        @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
        @Column(name = "storypost_id")
        var id: Long,
        var body: String,
        var video_link: String,
        var image_link: String,
        var likes: Int,
        @ManyToOne(fetch = FetchType.EAGER)
        @JoinColumn(name = "userprofile_id")
        @JsonBackReference
        var userProfile: UserProfile?=null
)

Controller

@RestController
class StoryPostController ( val repo : StoryPostRepositories){


    @GetMapping("/storypost")
    fun getAllStoryPosts() = repo.findAll().toList()

    @PostMapping("/storypost")
    fun addStoryPost(@RequestBody userPost : StoryPost) : ResponseEntity<StoryPost>{
        repo.save(userPost)
        return ResponseEntity<StoryPost>(userPost, HttpStatus.CREATED)
    }
}

how would I include the user id when making a storypost post request? should i just put another var

user_id: Long

and then have a

val repo2 : UserRepo

to find by id?

In Sebastian's latest presentation, he mentioned we can help convert the Spring Boot samples to Kotlin to help his workload....anyone know how we can do that? https://blog.jetbrains.com/kotlin/2020/08/the-state-of-kotlin-support-in-spring/

hi there. Has anyone bumped kotlin to 1.4 in SB project already? 😃

so I’d like to make several requests to several feeds to retrieve the articles of each feed and store them in my own DB

I’ve just developed some easy RESTful APIs but never done such thing 🙂

Hello! 👋 I’m hitting a problem with conditional bean creation order - I’m writing custom bean registrar to generate and register some beans based on the configuration properties and I provide some default beans as a fallback. Basically • I got an annotation for explicit opt-in where I import my registrar and fallback config • registrar is environment aware so it can bind my properties and uses factory bean to create target beans (e.g.

BeanDefinitionBuilder.genericBeanDefinition(MyFactoryBean::class.java)

•

MyFactoryBean

is application context aware and it attempts to retrieve

FallbackBean

from context (e.g. using

applicationContext.getBean(FallbackBean::class.java)

• within a

@SpringBootTest

I’m explicitly creating

SomeBean

in a configuration class So my problem is that conditional logic (i.e.

@ConditionalOnBean

) is evaluated BEFORE attempting to create the

SomeBean

in test configuration…. Sample code in the thread. Any ideas what I might be missing?

Hey! I've been migrating a simple project from Spring MVC to Webflux (with Netty). I did a rough load test attempt locally, to see if response times were slower, but I found they actually seem to be higher (not a lot, let's say 10-15% higher). Could this be a symptom of me doing unintentional blocking or something like that?

Hi, I have a problem with spring boot 2.1.6 I tried to use kotlin bean dsl to declare beans and it works perfectly fine for the core app, but tests are failing (for tests I am using spring-boot-starter-test and kotest). I have read all the information I could find on stackoverflow and made these improvements: 1. Created

class BeansInitializer : ApplicationContextInitializer<GenericApplicationContext> {
   override fun initialize(context: GenericApplicationContext) {
       beans().initialize(context)
   }
}

2. Set context.initializer.classes=com.package.BeansInitializer in application.properties It helped a little bit, now some of the beans are created, but all beans with @ConfigurationsProperties are still not created.

hello! 👋 Is there are preferred visibility modifier for creating auto configuration libs? My co-worker insists on making those internal which seems wrong to me….

Hi guys I'm having issues with the mapstruct mapper in springboot

@Mapper
@Component
interface UserMapper {
    fun toUserDTO(user: User): UserDTO
    fun toListOfUserDTO(users: List<User>) : List<UserDTO>
    fun toUser(userDTO: UserDTO) : User
    fun toListOfUser(userDTOs: List<UserDTO>) : List<User>
}

and i'm using it in my contoller

@Autowired
lateinit var userMapper: UserMapper

It gives this error, please help

***************************

APPLICATION FAILED TO START *************************** Description: Field userMapper in com.scienta.backend_rated_ng.controller.AuthController required a bean of type 'com.scienta.backend_rated_ng.mapper.UserMapper' that could not be found. The injection point has the following annotations: - @org.springframework.beans.factory.annotation.Autowired(required=true) Action: Consider defining a bean of type 'com.scienta.backend_rated_ng.mapper.UserMapper' in your configuration. I have all my dependencies right

Hi! I'm playing around with the router dsl and its working great so far. However, I want to set up my Controller which handles thymeleaf too. I got this GET Endpoint:

@GetMapping("/")
    fun index(model: Model): String {
        model.addAttribute(....)
        return "index"
    }

and I would like to convert it to the new dsl.

router {
        accept(MediaType.TEXT_HTML).nest {
            GET("/") { index(/*model param missing*/) }
        }

Could one give me a hint how to handle the parameter

model: Model

accordingly? Thanks a lot!