Merge branch 'dev/3.0.0' into dev/5.0.0

api/src/main/java/com/velocitypowered/api/plugin/PluginContainer.java

@@ -8,6 +8,7 @@
 package com.velocitypowered.api.plugin;
 
 import java.util.Optional;
+import java.util.concurrent.ExecutorService;
 
 /**
  * A wrapper around a plugin loaded by the proxy.
@@ -29,4 +30,12 @@ public interface PluginContainer {
   default Optional<?> getInstance() {
     return Optional.empty();
   }
+
+  /**
+   * Returns an executor service for this plugin. The executor will use a cached
+   * thread pool.
+   *
+   * @return an {@link ExecutorService} associated with this plugin
+   */
+  ExecutorService getExecutorService();
 }

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/VelocityPluginContainer.java

@@ -17,9 +17,12 @@
 
 package com.velocitypowered.proxy.plugin.loader;
 
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import com.velocitypowered.api.plugin.PluginContainer;
 import com.velocitypowered.api.plugin.PluginDescription;
 import java.util.Optional;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
 
 /**
  * Implements {@link PluginContainer}.
@@ -28,6 +31,7 @@ public class VelocityPluginContainer implements PluginContainer {
 
   private final PluginDescription description;
   private Object instance;
+  private volatile ExecutorService service;
 
   public VelocityPluginContainer(PluginDescription description) {
     this.description = description;
@@ -46,4 +50,24 @@ public Optional<?> getInstance() {
   public void setInstance(Object instance) {
     this.instance = instance;
   }
+
+  @Override
+  public ExecutorService getExecutorService() {
+    if (this.service == null) {
+      synchronized (this) {
+        if (this.service == null) {
+          String name = this.description.getName().orElse(this.description.getId());
+          this.service = Executors.unconfigurableExecutorService(
+              Executors.newCachedThreadPool(
+                new ThreadFactoryBuilder().setDaemon(true)
+                    .setNameFormat(name + " - Task Executor #%d")
+                    .build()
+              )
+          );
+        }
+      }
+    }
+
+    return this.service;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/java/VelocityPluginModule.java

@@ -25,6 +25,7 @@
 import com.velocitypowered.api.plugin.annotation.DataDirectory;
 import com.velocitypowered.api.proxy.ProxyServer;
 import java.nio.file.Path;
+import java.util.concurrent.ExecutorService;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -52,5 +53,7 @@ public void configure(Binder binder) {
         .toInstance(basePluginPath.resolve(description.getId()));
     binder.bind(PluginDescription.class).toInstance(description);
     binder.bind(PluginContainer.class).toInstance(pluginContainer);
+
+    binder.bind(ExecutorService.class).toProvider(pluginContainer::getExecutorService);
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/scheduler/VelocityScheduler.java

@@ -24,39 +24,39 @@
 import com.google.common.collect.Multimap;
 import com.google.common.collect.Multimaps;
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
+import com.velocitypowered.api.plugin.PluginContainer;
 import com.velocitypowered.api.plugin.PluginManager;
 import com.velocitypowered.api.scheduler.ScheduledTask;
 import com.velocitypowered.api.scheduler.Scheduler;
 import com.velocitypowered.api.scheduler.TaskStatus;
+import com.velocitypowered.proxy.plugin.loader.VelocityPluginContainer;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.IdentityHashMap;
+import java.util.Optional;
 import java.util.Set;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.ScheduledFuture;
-import java.util.concurrent.SynchronousQueue;
-import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import java.util.function.Consumer;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
+import org.jetbrains.annotations.VisibleForTesting;
 
 /**
  * The Velocity "scheduler", which is actually a thin wrapper around
  * {@link ScheduledExecutorService} and a dynamically-sized {@link ExecutorService}.
- * Many plugins are accustomed to the Bukkit Scheduler model although it is not relevant
+ * Many plugins are accustomed to the Bukkit Scheduler model, although it is not relevant
  * in a proxy context.
  */
 public class VelocityScheduler implements Scheduler {
 
-  private static final int MAX_SCHEDULER_POOLED_THREAD_CAP = 200;
-
   private final PluginManager pluginManager;
-  private final ExecutorService taskService;
   private final ScheduledExecutorService timerExecutionService;
   private final Multimap<Object, ScheduledTask> tasksByPlugin = Multimaps.synchronizedMultimap(
       Multimaps.newSetMultimap(new IdentityHashMap<>(), HashSet::new));
@@ -68,10 +68,6 @@ public class VelocityScheduler implements Scheduler {
    */
   public VelocityScheduler(PluginManager pluginManager) {
     this.pluginManager = pluginManager;
-    this.taskService = new ThreadPoolExecutor(1, MAX_SCHEDULER_POOLED_THREAD_CAP,
-        60L, TimeUnit.SECONDS, new SynchronousQueue<>(),
-        new ThreadFactoryBuilder().setDaemon(true)
-            .setNameFormat("Velocity Task Scheduler - #%d").build());
     this.timerExecutionService = Executors
         .newSingleThreadScheduledExecutor(new ThreadFactoryBuilder().setDaemon(true)
             .setNameFormat("Velocity Task Scheduler Timer").build());
@@ -81,16 +77,18 @@ public VelocityScheduler(PluginManager pluginManager) {
   public TaskBuilder buildTask(Object plugin, Runnable runnable) {
     checkNotNull(plugin, "plugin");
     checkNotNull(runnable, "runnable");
-    checkArgument(pluginManager.fromInstance(plugin).isPresent(), "plugin is not registered");
-    return new TaskBuilderImpl(plugin, runnable, null);
+    final Optional<PluginContainer> container = pluginManager.fromInstance(plugin);
+    checkArgument(container.isPresent(), "plugin is not registered");
+    return new TaskBuilderImpl(container.get(), runnable);
   }
 
   @Override
   public TaskBuilder buildTask(Object plugin, Consumer<ScheduledTask> consumer) {
     checkNotNull(plugin, "plugin");
     checkNotNull(consumer, "consumer");
-    checkArgument(pluginManager.fromInstance(plugin).isPresent(), "plugin is not registered");
-    return new TaskBuilderImpl(plugin, null, consumer);
+    final Optional<PluginContainer> container = pluginManager.fromInstance(plugin);
+    checkArgument(container.isPresent(), "plugin is not registered");
+    return new TaskBuilderImpl(container.get(), consumer);
   }
 
   @Override
@@ -118,22 +116,55 @@ public boolean shutdown() throws InterruptedException {
       task.cancel();
     }
     timerExecutionService.shutdown();
-    taskService.shutdown();
-    return taskService.awaitTermination(10, TimeUnit.SECONDS);
+    for (final PluginContainer container : this.pluginManager.getPlugins()) {
+      if (container instanceof VelocityPluginContainer) {
+        (container).getExecutorService().shutdown();
+      }
+    }
+
+    boolean allShutdown = true;
+    for (final PluginContainer container : this.pluginManager.getPlugins()) {
+      if (!(container instanceof VelocityPluginContainer)) {
+        continue;
+      }
+      final String id = container.getDescription().getId();
+      final ExecutorService service = (container).getExecutorService();
+
+      try {
+        if (!service.awaitTermination(10, TimeUnit.SECONDS)) {
+          service.shutdownNow();
+          Log.logger.warn("Executor for plugin {} did not shut down within 10 seconds. "
+              + "Continuing with shutdown...", id);
+          allShutdown = false;
+        }
+
+      } catch (final InterruptedException e) {
+        Log.logger.warn("Executor for plugin {} did not shut down within 10 seconds. "
+            + "Continuing with shutdown...", id);
+      }
+    }
+
+    return allShutdown;
   }
 
   private class TaskBuilderImpl implements TaskBuilder {
 
-    private final Object plugin;
+    private final PluginContainer container;
     private final Runnable runnable;
     private final Consumer<ScheduledTask> consumer;
     private long delay; // ms
     private long repeat; // ms
 
-    private TaskBuilderImpl(Object plugin, Runnable runnable, Consumer<ScheduledTask> consumer) {
-      this.plugin = plugin;
-      this.runnable = runnable;
+    private TaskBuilderImpl(PluginContainer container, Consumer<ScheduledTask> consumer) {
+      this.container = container;
       this.consumer = consumer;
+      this.runnable = null;
+    }
+
+    private TaskBuilderImpl(PluginContainer container, Runnable runnable) {
+      this.container = container;
+      this.consumer = null;
+      this.runnable = runnable;
     }
 
     @Override
@@ -162,26 +193,27 @@ public TaskBuilder clearRepeat() {
 
     @Override
     public ScheduledTask schedule() {
-      VelocityTask task = new VelocityTask(plugin, runnable, consumer, delay, repeat);
-      tasksByPlugin.put(plugin, task);
+      VelocityTask task = new VelocityTask(container, runnable, consumer, delay, repeat);
+      tasksByPlugin.put(container.getInstance().get(), task);
       task.schedule();
       return task;
     }
   }
 
-  private class VelocityTask implements Runnable, ScheduledTask {
+  @VisibleForTesting
+  class VelocityTask implements Runnable, ScheduledTask {
 
-    private final Object plugin;
+    private final PluginContainer container;
     private final Runnable runnable;
     private final Consumer<ScheduledTask> consumer;
     private final long delay;
     private final long repeat;
     private @Nullable ScheduledFuture<?> future;
     private volatile @Nullable Thread currentTaskThread;
 
-    private VelocityTask(Object plugin, Runnable runnable, Consumer<ScheduledTask> consumer,
-        long delay, long repeat) {
-      this.plugin = plugin;
+    private VelocityTask(PluginContainer container, Runnable runnable,
+        Consumer<ScheduledTask> consumer, long delay, long repeat) {
+      this.container = container;
       this.runnable = runnable;
       this.consumer = consumer;
       this.delay = delay;
@@ -199,7 +231,8 @@ void schedule() {
 
     @Override
     public Object plugin() {
-      return plugin;
+      //noinspection OptionalGetWithoutIsPresent
+      return container.getInstance().get();
     }
 
     @Override
@@ -235,7 +268,7 @@ public void cancel() {
 
     @Override
     public void run() {
-      taskService.execute(() -> {
+      container.getExecutorService().execute(() -> {
         currentTaskThread = Thread.currentThread();
         try {
           if (runnable != null) {
@@ -248,11 +281,10 @@ public void run() {
           if (e instanceof InterruptedException) {
             Thread.currentThread().interrupt();
           } else {
-            String friendlyPluginName = pluginManager.fromInstance(plugin)
-                .map(container -> container.getDescription().getName()
-                    .orElse(container.getDescription().getId()))
-                .orElse("UNKNOWN");
-            Log.logger.error("Exception in task {} by plugin {}", runnable, friendlyPluginName,
+            String friendlyPluginName = container.getDescription().getName()
+                .orElse(container.getDescription().getId());
+            Object unit = consumer == null ? runnable : consumer;
+            Log.logger.error("Exception in task {} by plugin {}", unit, friendlyPluginName,
                 e);
           }
         } finally {
@@ -265,7 +297,17 @@ public void run() {
     }
 
     private void onFinish() {
-      tasksByPlugin.remove(plugin, this);
+      tasksByPlugin.remove(plugin(), this);
+    }
+
+    public void awaitCompletion() {
+      try {
+        future.get();
+      } catch (InterruptedException e) {
+        Thread.currentThread().interrupt();
+      } catch (ExecutionException e) {
+        throw new RuntimeException(e);
+      }
     }
   }
 

proxy/src/test/java/com/velocitypowered/proxy/scheduler/VelocitySchedulerTest.java

@@ -21,6 +21,7 @@
 
 import com.velocitypowered.api.scheduler.ScheduledTask;
 import com.velocitypowered.api.scheduler.TaskStatus;
+import com.velocitypowered.proxy.scheduler.VelocityScheduler.VelocityTask;
 import com.velocitypowered.proxy.testutil.FakePluginManager;
 import java.time.Duration;
 import java.util.concurrent.CountDownLatch;
@@ -39,6 +40,7 @@ void buildTask() throws Exception {
     ScheduledTask task = scheduler.buildTask(FakePluginManager.PLUGIN_A, latch::countDown)
         .schedule();
     latch.await();
+    ((VelocityTask) task).awaitCompletion();
     assertEquals(TaskStatus.FINISHED, task.status());
   }
 
@@ -50,7 +52,6 @@ void cancelWorks() throws Exception {
         .delay(100, TimeUnit.SECONDS)
         .schedule();
     task.cancel();
-    Thread.sleep(200);
     assertEquals(3, i.get());
     assertEquals(TaskStatus.CANCELLED, task.status());
   }
@@ -70,23 +71,26 @@ void repeatTaskWorks() throws Exception {
   @Test
   void obtainTasksFromPlugin() throws Exception {
     VelocityScheduler scheduler = new VelocityScheduler(new FakePluginManager());
-    AtomicInteger i = new AtomicInteger(0);
-    CountDownLatch latch = new CountDownLatch(1);
+    CountDownLatch runningLatch = new CountDownLatch(1);
+    CountDownLatch endingLatch = new CountDownLatch(1);
 
     scheduler.buildTask(FakePluginManager.PLUGIN_A, task -> {
-      if (i.getAndIncrement() >= 1) {
-        task.cancel();
-        latch.countDown();
+      runningLatch.countDown();
+      task.cancel();
+      try {
+        endingLatch.await();
+      } catch (InterruptedException ignored) {
+        Thread.currentThread().interrupt();
       }
     }).delay(50, TimeUnit.MILLISECONDS)
         .repeat(Duration.ofMillis(5))
         .schedule();
 
-    assertEquals(scheduler.tasksByPlugin(FakePluginManager.PLUGIN_A).size(), 1);
+    runningLatch.await();
 
-    latch.await();
+    assertEquals(scheduler.tasksByPlugin(FakePluginManager.PLUGIN_A).size(), 1);
 
-    assertEquals(scheduler.tasksByPlugin(FakePluginManager.PLUGIN_A).size(), 0);
+    endingLatch.countDown();
   }
 
   @Test