Allow dropLataData in GBK for SamzaRunner

runners/samza/src/main/java/org/apache/beam/runners/samza/SamzaPipelineOptions.java

@@ -173,4 +173,10 @@ public ExecutorService create(PipelineOptions options) {
           new ThreadFactoryBuilder().setNameFormat("Process Element Thread-%d").build());
     }
   }
+
+  @Description("Enable/disable late data dropping in GroupByKey/Combine transforms")
+  @Default.Boolean(false)
+  boolean getDropLateData();
+
+  void setDropLateData(boolean dropLateData);
 }

runners/samza/src/main/java/org/apache/beam/runners/samza/runtime/GroupByKeyOp.java

@@ -180,11 +180,19 @@ public TimerInternals timerInternals() {
             DoFnSchemaInformation.create(),
             Collections.emptyMap());
 
+    final DoFnRunner<KeyedWorkItem<K, InputT>, KV<K, OutputT>> dropLateDataRunner =
+        pipelineOptions.getDropLateData()
+            ? DoFnRunners.lateDataDroppingRunner(
+                doFnRunner, keyedInternals.timerInternals(), windowingStrategy)
+            : doFnRunner;
+
     final SamzaExecutionContext executionContext =
         (SamzaExecutionContext) context.getApplicationContainerContext();
-    this.fnRunner =
+    final DoFnRunner<KeyedWorkItem<K, InputT>, KV<K, OutputT>> doFnRunnerWithMetrics =
         DoFnRunnerWithMetrics.wrap(
-            doFnRunner, executionContext.getMetricsContainer(), transformFullName);
+            dropLateDataRunner, executionContext.getMetricsContainer(), transformFullName);
+
+    this.fnRunner = new DoFnRunnerWithKeyedInternals<>(doFnRunnerWithMetrics, keyedInternals);
   }
 
   @Override

runners/samza/src/test/java/org/apache/beam/runners/samza/runtime/GroupByKeyOpTest.java

@@ -0,0 +1,123 @@
+/*
+ * 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.beam.runners.samza.runtime;
+
+import java.io.Serializable;
+import java.util.Arrays;
+import org.apache.beam.sdk.coders.KvCoder;
+import org.apache.beam.sdk.coders.StringUtf8Coder;
+import org.apache.beam.sdk.coders.VarIntCoder;
+import org.apache.beam.sdk.options.PipelineOptionsFactory;
+import org.apache.beam.sdk.testing.PAssert;
+import org.apache.beam.sdk.testing.TestPipeline;
+import org.apache.beam.sdk.testing.TestStream;
+import org.apache.beam.sdk.transforms.Combine;
+import org.apache.beam.sdk.transforms.Sum;
+import org.apache.beam.sdk.transforms.windowing.FixedWindows;
+import org.apache.beam.sdk.transforms.windowing.Window;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TimestampedValue;
+import org.joda.time.Duration;
+import org.joda.time.Instant;
+import org.junit.Rule;
+import org.junit.Test;
+
+/** Tests for GroupByKeyOp. */
+public class GroupByKeyOpTest implements Serializable {
+  @Rule
+  public final transient TestPipeline pipeline =
+      TestPipeline.fromOptions(
+          PipelineOptionsFactory.fromArgs("--runner=TestSamzaRunner").create());
+
+  @Rule
+  public final transient TestPipeline dropLateDataPipeline =
+      TestPipeline.fromOptions(
+          PipelineOptionsFactory.fromArgs("--runner=TestSamzaRunner", "--dropLateData=true")
+              .create());
+
+  @Test
+  public void testDefaultGbk() {
+    TestStream.Builder<Integer> testStream =
+        TestStream.create(VarIntCoder.of())
+            .addElements(TimestampedValue.of(1, new Instant(1000)))
+            .addElements(TimestampedValue.of(2, new Instant(2000)))
+            .advanceWatermarkTo(new Instant(3000))
+            .addElements(TimestampedValue.of(10, new Instant(1000)))
+            .advanceWatermarkTo(new Instant(10000));
+
+    PCollection<Integer> aggregated =
+        pipeline
+            .apply(testStream.advanceWatermarkToInfinity())
+            .apply(
+                Window.<Integer>into(FixedWindows.of(Duration.standardSeconds(3)))
+                    .accumulatingFiredPanes())
+            .apply(Combine.globally(Sum.ofIntegers()).withoutDefaults());
+
+    PAssert.that(aggregated).containsInAnyOrder(Arrays.asList(3, 10));
+
+    pipeline.run().waitUntilFinish();
+  }
+
+  @Test
+  public void testDropLateDataNonKeyed() {
+    TestStream.Builder<Integer> testStream =
+        TestStream.create(VarIntCoder.of())
+            .addElements(TimestampedValue.of(1, new Instant(1000)))
+            .addElements(TimestampedValue.of(2, new Instant(2000)))
+            .advanceWatermarkTo(new Instant(3000))
+            .addElements(TimestampedValue.of(10, new Instant(1000)))
+            .advanceWatermarkTo(new Instant(10000));
+
+    PCollection<Integer> aggregated =
+        dropLateDataPipeline
+            .apply(testStream.advanceWatermarkToInfinity())
+            .apply(
+                Window.<Integer>into(FixedWindows.of(Duration.standardSeconds(3)))
+                    .accumulatingFiredPanes())
+            .apply(Combine.globally(Sum.ofIntegers()).withoutDefaults());
+
+    PAssert.that(aggregated).containsInAnyOrder(3);
+
+    dropLateDataPipeline.run().waitUntilFinish();
+  }
+
+  @Test
+  public void testDropLateDataKeyed() {
+    TestStream.Builder<KV<String, Integer>> testStream =
+        TestStream.create(KvCoder.of(StringUtf8Coder.of(), VarIntCoder.of()))
+            .addElements(TimestampedValue.of(KV.of("a", 1), new Instant(1000)))
+            .addElements(TimestampedValue.of(KV.of("b", 2), new Instant(2000)))
+            .addElements(TimestampedValue.of(KV.of("a", 3), new Instant(2500)))
+            .advanceWatermarkTo(new Instant(3000))
+            .addElements(TimestampedValue.of(KV.of("a", 10), new Instant(1000)))
+            .advanceWatermarkTo(new Instant(10000));
+
+    PCollection<KV<String, Integer>> aggregated =
+        dropLateDataPipeline
+            .apply(testStream.advanceWatermarkToInfinity())
+            .apply(
+                Window.<KV<String, Integer>>into(FixedWindows.of(Duration.standardSeconds(3)))
+                    .accumulatingFiredPanes())
+            .apply(Sum.integersPerKey());
+
+    PAssert.that(aggregated).containsInAnyOrder(Arrays.asList(KV.of("a", 4), KV.of("b", 2)));
+
+    dropLateDataPipeline.run().waitUntilFinish();
+  }
+}