Hello, what is the recommended orm library for kotlin spring boot? JPA, JOOQ, or something else？

Hey folks! What are the (FOSS?) options I have for enabling hot reloading in kotlin/ktor app?

Hello, sorry if this is a very basic question I have base experience as a backend developer using golang. I only moved to Kotlin recently, and I want to use a library I wrote in golang for my current project. I tried to read articles and documentations, for example this one: https://kotlinlang.org/docs/multiplatform-library.html Question: is there a good example how a proper and production ready library of a kotlin project should look like? a good simple library would do, I just need to understand how things are written in kotlin before I will be confident enough to write my old golang library to kotlin/java. It would be great if the library is simple enough to learn from. For context, the library is a utility library that can be use in all backend/frontend/android projects. Thank you in advance!

Hey guys, need some input. At a high-level, I am building a social media app with react native as the FrontEnd and for my backend I am using Kotlin, however any thoughts on if I should go with SpringBoot or KTor framework? This app is mobile first (IOS/Android) and Web 2nd.

Hey guys, i have a question. Does ktor can publish your app without cloud? Just using your own computer and server?

What is the popular library to run jobs in background on a ktor server?

Is there a way to load the ktor server environment in kotlin shell?

Hello, I hope everyone is doing good. I'm maintaining a Kotlin multiplatform library called Kotools Types and would like to make it compatible with Java in the future. The majority of types provided by this library are inline value classes, making their declarations incompatible with Java by definition. Do you have any tips for improving the Kotlin interoperability with Java? A solution could be to disable mangling by marking their declarations with the

JvmName

annotation. Another one could be to convert these inline value classes to regular ones, but we will lose their performance benefits... Also, when analyzing the binary code, I notice that using these type of classes narrows our understanding of it: the compiler replaces them by their underlying type. So I'm thinking about their tradeoff on performance and readability. Do you have any thoughts on this? Thanks!

Hello everyone 👋 I have an api-gateway written in kotlin (using ktor) for my microservices app. One of my new services is a node.js app streaming audio. I'm having difficulties in building my route to this streaming endpoint. Everything I've done on my api-gateway so far was to forward the request and copy the response from the inner service to the client. But I'm not sure how to build it for this streaming endpoint. I'm a Java and JavaScript developer but I'm trying to get in touch with Kotlin, that's why there's a mix of tech stacks in my app. I'll paste my current implementation on the thread. The message I'm getting from my api-gateway is a 504 timeout error. Therefore the large timeout.

Hola a todos, alguien a implementado el api de google drive con service account junto con sprint boot y kotlin, estoy teniendo problemas con las librerias, de antemano les agradezco.

I'm implementing this interface (see IndexRecord ) which is a container for a decoded Avro object. It feels like the natural way to represent the record is a data class but I'm getting hung up on the fact that deserializer wants to instantiate my record and iteratively call

put

on each field. Since my data class would need an empty constructor I'd have to set defaults or make all of my fields optional, but neither seems ideal. Is there some trick or alternative to data classes that I could use or should I just be using a plain old class for this instead?

Hey, a question on handling coroutines. Basically, I want to have websocket a websocket client that connects to some other server. Does it look legit or there are better ways to do it without GlobalScope Not sure what will happen when both websocket and API will try to modify same data but I guess I will find out

fun main() {
    GlobalScope.launch {
        val client = HttpClient(CIO) {
            install(WebSockets) {
                pingInterval = 40_000
                            }
        }
        println("sendingxxx")
        client.wss(host = "<http://example.com|example.com>", path = "/socket/websocket") {
        }
    }

    embeddedServer(Netty, port = 8083, host = "0.0.0.0", module = Application::module)
        .start(wait = true)
}

fun Application.module() {
    configureSecurity()
    configureSerialization()
    configureRouting()
}

can you not add websockets to the netty server? (I forgor to reply to the message above in a thread)

This message was deleted.

Hello everyone! Does ktor can help me build self own server in my computer with real time database? If so, can you send some tutorial or links. Thank you!

I posted multichannel so i leave link only one post. https://kotlinlang.slack.com/archives/C4GKV43N2/p1694159243720809

Hello everyone! Does this site still applicable until now? Or there's another solution for that connect the database that is a secure https://idiallo.com/blog/dont-connect-directly-to-your-database

I'm running into an issue where logback using

ch.qos.logback.classic.encoder.JsonEncoder

doesn't want to serialize

kotlinx.datetime.LocalDateTime

It seems that the underlying encoder uses Jackson and I'm wondering if I have to pass something special to the encoder to make it work? Can't seem to find any info online about that and wondering if someone has run across this before.

hi everyone, how do you use

either

for handler different errors

Hello I'm trying to add datadog tracer in my ktor application, but the documentation is very poor has anyone done this before?

Hello, I am trying to implement a global exception handler in spring boot kotlin, here is my code

import org.springframework.http.HttpStatus
import org.springframework.http.ResponseEntity
import org.springframework.web.bind.annotation.ControllerAdvice
import org.springframework.web.bind.annotation.ExceptionHandler
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler



@ControllerAdvice
class GlobalExceptionHandler {

    @ExceptionHandler(Exception::class)
    fun handleGenericException(ex: Exception): ResponseEntity<Any> {
        val errorMessage = "An unexpected error occurred: ${ex.message}"
        return ResponseEntity(errorMessage, HttpStatus.INTERNAL_SERVER_ERROR)
    }

    @ExceptionHandler(value = [ArithmeticException::class])
    fun handleArithmeticException(ex: ArithmeticException): ResponseEntity<Any> {
        val errorMessage = "An arithmetic error occurred: ${ex.message}"
        return ResponseEntity(errorMessage, HttpStatus.INTERNAL_SERVER_ERROR)
    }

    @ExceptionHandler(RuntimeException::class)
    fun handleRuntimeException(exception: RuntimeException): ResponseEntity<Any> {
        return ResponseEntity
            .status(HttpStatus.INTERNAL_SERVER_ERROR)
            .body("abc bab")
    }

}

Issue I am facing right now is that when i throw an exception in my controller, it is not invoking the GlobalExceptionHandler, here is the controller code.

package com.example.balancesservice


import org.apache.http.HttpStatus
import org.springframework.http.HttpStatusCode
import org.springframework.http.ResponseEntity
import org.springframework.web.bind.annotation.GetMapping
import org.springframework.web.bind.annotation.RestController
import org.springframework.web.server.ResponseStatusException

@RestController
class HealthController {

    @GetMapping("/health")
    fun healthCheck(): String {
            throw Exception("Div by zero not all")

    }
}

Can anyone please guide?

Hello everyone!

@khan husnain try to remove handleGenericException method

I'm getting this error when trying to generate code using protobuf the users class always seems to generate by default and i'm not sure why even if i rename the class or package in the protobuf file. I don't have a class named users anywhere else

Hi everyone, I released a Kotlin GCP PubSub library today, it has several different modules to integrate with KotlinX Coroutines, KotlinX Serialization, and Ktor 🥳 Hope you enjoy it, any feedback is welcome! https://github.com/nomisRev/kotlin-gcp-pubsub

Any thoughts, best practices around objects vs. top level function declarations for related but independent functions? I'm assuming there's some overhead in creating a static object but is it negligible? The benefit feels like slightly better development experience being able to have auto complete when using the functions.

Hi I am trying to use context receivers with Exposed in order to pass the transaction What would be great, would be to have optionally a transaction in the context, something like

context(Transaction?)
fun doStatementReuseOrCreateTransaction(statement: suspend Transaction.() -> Unit) {
  if (this@Transaction == null) {
    openTransaction {
      statement()
    }
  } else statement()
}

However as soon as I make the context optional (with the

?

) then intellij is lost and doesn't understand

this@Transaction

anymore is there any way to make it work?

Hello... there is no channel for Kotlin-DL, so if there anyone that can help with this in Spring boot, i will be really thankful... I'm trying to find a way to use `tensorflow`model in

Spring Boot

, I loaded the model successfully, and created the needed tensor, but I can't make a call to get the result from the model because of this error:

Caused by: org.tensorflow.exceptions.TFInvalidArgumentException: Expects arg[0] to be float but uint8 is provided

I checked the model signature and it was like this:

Method: "tensorflow/serving/predict"
    Inputs:
        "input_1": dtype=DT_FLOAT, shape=(-1, 299, 299, 3)
    Outputs:
        "dense_3": dtype=DT_FLOAT, shape=(-1, 41)

Signature for "__saved_model_init_op":
    Outputs:
        "__saved_model_init_op": dtype=DT_INVALID, shape=()

my tensor details are

DT_UINT8 tensor with shape [299, 299, 3]

. When I changed my tensor data type into float like this:

val imageShape = TFloat32.tensorOf(runner.fetch(decodeImage).run()[0].shape())
        val reshape = tf.reshape(
            decodeImage,
            tf.array(
                -1.0f,
                imageShape[0].getFloat(),
                imageShape[1].getFloat(),
                imageShape[2].getFloat())
            )

I got this error:

org.tensorflow.exceptions.TFInvalidArgumentException: Value for attr 'Tshape' of float is not in the list of allowed values: int32, int64

how can I fix this problem? if someone is curious how I loaded the model, created the tensor and called it, here is the code below Loading the model in `TFServices`:

fun model(): SavedModelBundle  {
        return SavedModelBundle
            .loader("/home/saher/kotlin/Spring/machinelearning/src/main/resources/pd/")
            .withRunOptions(RunOptions.getDefaultInstance())
            .load()
    }

Building the Tensor and calling the model

val graph = Graph()
        val session = Session(graph)
        val tf = Ops.create(graph)
        val fileName = tf.constant("/home/***/src/main/resources/keyframe_1294.jpg")
        val readFile = tf.io.readFile(fileName)
        val runner = session.runner()
        val decodingOptions = DecodeJpeg.channels(3)
        val decodeImage = tf.image.decodeJpeg(readFile.contents(), decodingOptions)
        val imageShape = runner.fetch(decodeImage).run()[0].shape()
        val reshape = tf.reshape(
            decodeImage,
            tf.array(
                -1,
                imageShape.asArray()[0],
                imageShape.asArray()[1],
                imageShape.asArray()[2])
            )
        val tensor = runner.fetch(reshape).run()[0]
        val inputMap = mutableMapOf("input_tensor" to tensor)
        println(tensor.shape())
        println(tensor.dataType())
        println(tensor.asRawTensor())
        val result = tfService.model().function("serving_default").call(inputMap)

regards

Assuming you have an internal service (ie inaccessible by the public), is there any benefit to having the health check run on a different port from the service? I feel like if it runs on a completely different port, it's less able to detect whether there's a problem with the actual service. Yet having a service and health port is something I see recommended quite frequently.

Hello, hope everyone is doing good. Does Kotlin has a Long Term Support (LTS) version like Java ? I can't find any resource on this topic...