Retry with exponential back off using flow

Retry.kt

import kotlinx.coroutines.*
import kotlinx.coroutines.flow.*
import java.io.IOException
import kotlin.math.pow

fun <T> Flow<T>.retryWithExponentialBackoff(
    times: Int,
    initialDelay: Long,
    factor: Double
): Flow<T> =
    retryWhen { cause, attempt ->
        if (cause is IOException && attempt < times) {
            val delayTime = (initialDelay * factor.pow(attempt.toDouble())).toLong()
            println("Retrying in ${delayTime}ms due to: ${cause.message}")
            delay(delayTime)
            true
        } else {
            false
        }
    }

fun main() = runBlocking<Unit> {
    val retryTimes = 3
    val initialDelay = 1000L // 1 second
    val factor = 2.0

    getRandomNumberFlow()
        .retryWithExponentialBackoff(retryTimes, initialDelay, factor)
        .catch { e -> println("Failed after $retryTimes retries due to: ${e.message}") }
        .collect { value -> println("Collected value: $value") }
}

fun getRandomNumberFlow(): Flow<Int> = flow {
    emit((1..10).random())
    throw IOException("IO error occurred!")
}