Prototype EventDispatcher

mirai-core-utils/src/commonMain/kotlin/CoroutineUtils.kt

@@ -75,4 +75,17 @@ public fun CoroutineContext.childScopeContext(
 public inline fun <E : U, U : CoroutineContext.Element> CoroutineContext.getOrElse(
     key: CoroutineContext.Key<E>,
     default: () -> U
-): U = this[key] ?: default()
+): U = this[key] ?: default()
+
+public inline fun <E : CoroutineContext.Element> CoroutineContext.addIfAbsent(
+    key: CoroutineContext.Key<E>,
+    default: () -> CoroutineContext.Element
+): CoroutineContext = if (this[key] == null) this + default() else this
+
+public inline fun CoroutineContext.addNameIfAbsent(
+    name: () -> String
+): CoroutineContext = addIfAbsent(CoroutineName) { CoroutineName(name()) }
+
+public fun CoroutineContext.addNameHierarchically(
+    name: String
+): CoroutineContext = this + CoroutineName(this[CoroutineName]?.name?.plus('.')?.plus(name) ?: name)

mirai-core/src/commonMain/kotlin/network/components/EventDispatcher.kt

@@ -0,0 +1,70 @@
+/*
+ * Copyright 2019-2021 Mamoe Technologies and contributors.
+ *
+ *  此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ *  Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
+ *
+ *  https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
+package net.mamoe.mirai.internal.network.components
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.job
+import kotlinx.coroutines.launch
+import net.mamoe.mirai.event.Event
+import net.mamoe.mirai.event.broadcast
+import net.mamoe.mirai.internal.network.component.ComponentKey
+import net.mamoe.mirai.utils.MiraiLogger
+import net.mamoe.mirai.utils.addNameHierarchically
+import net.mamoe.mirai.utils.childScope
+import kotlin.coroutines.CoroutineContext
+import kotlin.coroutines.EmptyCoroutineContext
+
+internal interface EventDispatcher {
+    suspend fun broadcast(event: Event)
+    fun broadcastAsync(event: Event, additionalContext: CoroutineContext = EmptyCoroutineContext)
+
+    /**
+     * Join all jobs. Joins also jobs launched during this call.
+     */
+    suspend fun joinBroadcast()
+
+    companion object : ComponentKey<EventDispatcher>
+}
+
+
+internal class EventDispatcherImpl(
+    private val lifecycleContext: CoroutineContext,
+    private val logger: MiraiLogger,
+) : EventDispatcher,
+    CoroutineScope by lifecycleContext
+        .addNameHierarchically("EventDispatcher")
+        .childScope() {
+
+    override suspend fun broadcast(event: Event) {
+        try {
+            event.broadcast()
+        } catch (e: Exception) {
+            if (logger.isEnabled) {
+                val msg = optimizeEventToString(event)
+                logger.error(IllegalStateException("Exception while broadcasting event '$msg'", e))
+            }
+        }
+    }
+
+    override fun broadcastAsync(event: Event, additionalContext: CoroutineContext) {
+        launch(additionalContext) { broadcast(event) }
+    }
+
+    private fun optimizeEventToString(event: Event): String {
+        val qualified = event::class.java.canonicalName ?: return event.toString()
+        return qualified.substringAfter("net.mamoe.mirai.event.events.", "").ifEmpty { event.toString() }
+    }
+
+    override suspend fun joinBroadcast() {
+        for (child in coroutineContext.job.children) {
+            child.join()
+        }
+    }
+}

mirai-core/src/commonMain/kotlin/network/components/PacketHandler.kt

@@ -11,15 +11,14 @@ package net.mamoe.mirai.internal.network.components
 
 import kotlinx.coroutines.CoroutineName
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.launch
 import net.mamoe.mirai.event.BroadcastControllable
 import net.mamoe.mirai.event.CancellableEvent
 import net.mamoe.mirai.event.Event
-import net.mamoe.mirai.event.broadcast
 import net.mamoe.mirai.internal.QQAndroidBot
 import net.mamoe.mirai.internal.network.MultiPacket
 import net.mamoe.mirai.internal.network.Packet
 import net.mamoe.mirai.internal.network.component.ComponentKey
+import net.mamoe.mirai.internal.network.component.ComponentStorage
 import net.mamoe.mirai.internal.network.protocol.packet.*
 import net.mamoe.mirai.utils.MiraiLogger
 import net.mamoe.mirai.utils.cast
@@ -65,6 +64,7 @@ internal class LoggingPacketHandlerAdapter(
 
 internal class EventBroadcasterPacketHandler(
     private val targetScope: CoroutineScope,
+    private val components: ComponentStorage,
     private val logger: MiraiLogger,
 ) : PacketHandler {
 
@@ -74,7 +74,7 @@ internal class EventBroadcasterPacketHandler(
     }
 
     private val coroutineName = CoroutineName("Mirai-EventDispatcher-${logger.identity}")
-    private suspend fun impl(packet: Packet) {
+    private fun impl(packet: Packet) {
         if (packet is MultiPacket<*>) {
             for (p in packet) {
                 impl(p)
@@ -84,25 +84,11 @@ internal class EventBroadcasterPacketHandler(
             packet is CancellableEvent && packet.isCancelled -> return
             packet is BroadcastControllable && !packet.shouldBroadcast -> return
             packet is Event -> {
-                targetScope.launch(coroutineName) {
+                components[EventDispatcher].broadcastAsync(packet)
-                    try {
-                        packet.broadcast()
-                    } catch (e: Throwable) {
-                        if (logger.isEnabled) {
-                            val msg = optimizeEventToString(packet)
-                            logger.error(IllegalStateException("Exception while broadcasting event '$msg'", e))
-                        }
-                    }
-                }
             }
         }
     }
 
-    private fun optimizeEventToString(event: Event): String {
-        val qualified = event::class.java.canonicalName ?: return this.toString()
-        return qualified.substringAfter("net.mamoe.mirai.event.events.")
-    }
-
     override fun toString(): String = "EventBroadcasterPacketHandler"
 }