add subscribeAsync

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## 0.5.14
 
+* `Coroutines`
+    * `subscribeSafelyWithoutExceptions` got new parameter `onException` by analogue with `safelyWithoutExceptions`
+    * New extensions `Flow#subscribeAsync` and subsequent analogs of `subscribe` with opportunity to set up custom marker
+
 ## 0.5.13
 
 * `Common`:

coroutines/src/commonMain/kotlin/dev/inmo/micro_utils/coroutines/FlowSubscription.kt

@@ -4,6 +4,8 @@ package dev.inmo.micro_utils.coroutines
 
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.flow.*
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
 
 /**
  * Shortcut for chain if [Flow.onEach] and [Flow.launchIn]
@@ -29,9 +31,10 @@ inline fun <T> Flow<T>.subscribeSafely(
  */
 inline fun <T> Flow<T>.subscribeSafelyWithoutExceptions(
     scope: CoroutineScope,
+    noinline onException: ExceptionHandler<T?> = defaultSafelyWithoutExceptionHandlerWithNull,
     noinline block: suspend (T) -> Unit
 ) = subscribe(scope) {
-    safelyWithoutExceptions {
+    safelyWithoutExceptions(onException) {
         block(it)
     }
 }

coroutines/src/commonMain/kotlin/dev/inmo/micro_utils/coroutines/FlowSubscriptionAsync.kt

@@ -0,0 +1,118 @@
+package dev.inmo.micro_utils.coroutines
+
+import kotlinx.coroutines.*
+import kotlinx.coroutines.channels.*
+import kotlinx.coroutines.flow.*
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+
+private class SubscribeAsyncReceiver<T>(
+    val scope: CoroutineScope,
+    output: suspend SubscribeAsyncReceiver<T>.(T) -> Unit
+) {
+    private val dataChannel: Channel<T> = Channel(Channel.UNLIMITED)
+    val channel: SendChannel<T>
+        get() = dataChannel
+
+    init {
+        scope.launchSafelyWithoutExceptions {
+            for (data in dataChannel) {
+                output(data)
+            }
+        }
+    }
+
+    fun isEmpty(): Boolean = dataChannel.isEmpty
+}
+
+private sealed interface AsyncSubscriptionCommand<T, M> {
+    suspend operator fun invoke(markersMap: MutableMap<M, SubscribeAsyncReceiver<T>>)
+}
+private data class AsyncSubscriptionCommandData<T, M>(
+    val data: T,
+    val scope: CoroutineScope,
+    val markerFactory: suspend (T) -> M,
+    val block: suspend (T) -> Unit,
+    val onEmpty: suspend (M) -> Unit
+) : AsyncSubscriptionCommand<T, M> {
+    override suspend fun invoke(markersMap: MutableMap<M, SubscribeAsyncReceiver<T>>) {
+        val marker = markerFactory(data)
+        markersMap.getOrPut(marker) {
+            SubscribeAsyncReceiver(scope) {
+                safelyWithoutExceptions { block(it) }
+                if (isEmpty()) {
+                    onEmpty(marker)
+                }
+            }
+        }.channel.send(data)
+    }
+}
+
+private data class AsyncSubscriptionCommandClearReceiver<T, M>(
+    val marker: M
+) : AsyncSubscriptionCommand<T, M> {
+    override suspend fun invoke(markersMap: MutableMap<M, SubscribeAsyncReceiver<T>>) {
+        val receiver = markersMap[marker]
+        if (receiver ?.isEmpty() == true) {
+            markersMap.remove(marker)
+            receiver.scope.cancel()
+        }
+    }
+}
+
+fun <T, M> Flow<T>.subscribeAsync(
+    scope: CoroutineScope,
+    markerFactory: suspend (T) -> M,
+    block: suspend (T) -> Unit
+): Job {
+    val subscope = scope.LinkedSupervisorScope()
+    val markersMap = mutableMapOf<M, SubscribeAsyncReceiver<T>>()
+    val actor = subscope.actor<AsyncSubscriptionCommand<T, M>>(Channel.UNLIMITED) {
+        it.invoke(markersMap)
+    }
+
+    val job = subscribeSafelyWithoutExceptions(subscope) { data ->
+        val dataCommand = AsyncSubscriptionCommandData(data, subscope, markerFactory, block) { marker ->
+            actor.send(
+                AsyncSubscriptionCommandClearReceiver(marker)
+            )
+        }
+        actor.send(dataCommand)
+    }
+
+    job.invokeOnCompletion { subscope.cancel() }
+
+    return job
+}
+
+inline fun <T, M> Flow<T>.subscribeSafelyAsync(
+    scope: CoroutineScope,
+    noinline markerFactory: suspend (T) -> M,
+    noinline onException: ExceptionHandler<Unit> = defaultSafelyExceptionHandler,
+    noinline block: suspend (T) -> Unit
+) = subscribeAsync(scope, markerFactory) {
+    safely(onException) {
+        block(it)
+    }
+}
+
+inline fun <T, M> Flow<T>.subscribeSafelyWithoutExceptionsAsync(
+    scope: CoroutineScope,
+    noinline markerFactory: suspend (T) -> M,
+    noinline onException: ExceptionHandler<T?> = defaultSafelyWithoutExceptionHandlerWithNull,
+    noinline block: suspend (T) -> Unit
+) = subscribeAsync(scope, markerFactory) {
+    safelyWithoutExceptions(onException) {
+        block(it)
+    }
+}
+
+inline fun <T, M> Flow<T>.subscribeSafelySkippingExceptionsAsync(
+    scope: CoroutineScope,
+    noinline markerFactory: suspend (T) -> M,
+    noinline block: suspend (T) -> Unit
+) = subscribeAsync(scope, markerFactory) {
+    safelyWithoutExceptions({ /* do nothing */}) {
+        block(it)
+    }
+}