[GitHub] [samza] bkonold commented on a change in pull request #1385: SAMZA-2550: Move side input processing to use RunLoop

[GitBox <gi...@apache.org>]

bkonold commented on a change in pull request #1385:
URL: https://github.com/apache/samza/pull/1385#discussion_r456763967



##########
File path: samza-core/src/main/java/org/apache/samza/storage/SideInputTask.java
##########
@@ -0,0 +1,124 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.samza.storage;
+
+import java.util.Collections;
+import java.util.Set;
+import org.apache.samza.checkpoint.OffsetManager;
+import org.apache.samza.container.RunLoopTask;
+import org.apache.samza.container.TaskInstanceMetrics;
+import org.apache.samza.container.TaskName;
+import org.apache.samza.scheduler.EpochTimeScheduler;
+import org.apache.samza.system.IncomingMessageEnvelope;
+import org.apache.samza.system.SystemStreamPartition;
+import org.apache.samza.task.ReadableCoordinator;
+import org.apache.samza.task.TaskCallback;
+import org.apache.samza.task.TaskCallbackFactory;
+
+
+/**
+ * This class encapsulates the processing logic for side input streams. It is executed by {@link org.apache.samza.container.RunLoop}
+ */
+public class SideInputTask implements RunLoopTask {
+  private final TaskName taskName;
+  private final Set<SystemStreamPartition> taskSSPs;
+  private final TaskSideInputHandler taskSideInputHandler;
+  private final TaskInstanceMetrics metrics;
+
+  public SideInputTask(
+      TaskName taskName,
+      Set<SystemStreamPartition> taskSSPs,
+      TaskSideInputHandler taskSideInputHandler,
+      TaskInstanceMetrics metrics) {
+    this.taskName = taskName;
+    this.taskSSPs = taskSSPs;
+    this.taskSideInputHandler = taskSideInputHandler;
+    this.metrics = metrics;
+  }
+
+  @Override
+  public TaskName taskName() {
+    return this.taskName;
+  }
+
+  @Override
+  public void process(IncomingMessageEnvelope envelope, ReadableCoordinator coordinator,
+      TaskCallbackFactory callbackFactory) {
+    TaskCallback callback = callbackFactory.createCallback();
+    this.metrics.processes().inc();
+    try {
+      this.taskSideInputHandler.process(envelope);
+      this.metrics.messagesActuallyProcessed().inc();

Review comment:
       No, the only existing side input metrics were emitted out of system consumers, and those will remain the same as the SystemConsumers instance remains the same but is just passed into RunLoop.
   
   The metrics (after this change) tracked in SamzaContainerMetrics and TaskInstanceMetrics are new. Can add this to the API section if you'd like, but there are no backwards incompatibilities.




----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org