Solace Read connector: watermark-calculation related classes

sdks/java/io/solace/src/main/java/org/apache/beam/sdk/io/solace/read/WatermarkParameters.java

@@ -0,0 +1,88 @@
+/*
+ * 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.sdk.io.solace.read;
+
+import com.google.auto.value.AutoValue;
+import java.io.Serializable;
+import org.apache.beam.sdk.transforms.SerializableFunction;
+import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
+import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.base.Preconditions;
+import org.joda.time.Duration;
+import org.joda.time.Instant;
+
+/** {@code WatermarkParameters} contains the parameters used for watermark computation. */
+@AutoValue
+abstract class WatermarkParameters<T> implements Serializable {
+
+  private static final Duration STANDARD_WATERMARK_IDLE_DURATION_THRESHOLD =
+      Duration.standardSeconds(30);
+
+  abstract Instant getCurrentWatermark();
+
+  abstract Instant getLastSavedWatermark();
+
+  abstract Instant getLastUpdateTime();
+
+  abstract SerializableFunction<T, Instant> getTimestampFn();
+
+  abstract Duration getWatermarkIdleDurationThreshold();
+
+  abstract Builder<T> toBuilder();
+
+  static <T> Builder<T> builder() {
+    return new AutoValue_WatermarkParameters.Builder<T>()
+        .setCurrentWatermark(BoundedWindow.TIMESTAMP_MIN_VALUE)
+        .setLastSavedWatermark(BoundedWindow.TIMESTAMP_MIN_VALUE)
+        .setLastUpdateTime(Instant.now())
+        .setWatermarkIdleDurationThreshold(STANDARD_WATERMARK_IDLE_DURATION_THRESHOLD);
+  }
+
+  @AutoValue.Builder
+  abstract static class Builder<T> {
+    abstract Builder<T> setCurrentWatermark(Instant currentWatermark);
+
+    abstract Builder<T> setLastSavedWatermark(Instant eventTime);
+
+    abstract Builder<T> setLastUpdateTime(Instant now);
+
+    abstract Builder<T> setWatermarkIdleDurationThreshold(Duration watermarkIdleDurationThreshold);
+
+    abstract Builder<T> setTimestampFn(SerializableFunction<T, Instant> timestampFn);
+
+    abstract WatermarkParameters<T> build();
+  }
+
+  /**
+   * Create an instance of {@link WatermarkParameters} with a {@code SerializableFunction} to
+   * extract the event time.
+   */
+  static <T> WatermarkParameters<T> create(SerializableFunction<T, Instant> timestampFn) {
+    Preconditions.checkArgument(timestampFn != null, "timestampFn function is null");
+    return WatermarkParameters.<T>builder().setTimestampFn(timestampFn).build();
+  }
+
+  /**
+   * Specify the watermark idle duration to consider before advancing the watermark. The default
+   * watermark idle duration threshold is {@link #STANDARD_WATERMARK_IDLE_DURATION_THRESHOLD}.
+   */
+  WatermarkParameters<T> withWatermarkIdleDurationThreshold(Duration idleDurationThreshold) {
+    Preconditions.checkArgument(
+        idleDurationThreshold != null, "watermark idle duration threshold is null");
+    return toBuilder().setWatermarkIdleDurationThreshold(idleDurationThreshold).build();
+  }
+}

sdks/java/io/solace/src/main/java/org/apache/beam/sdk/io/solace/read/WatermarkPolicy.java

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+/*
+ * 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.sdk.io.solace.read;
+
+import java.io.Serializable;
+import org.apache.beam.sdk.transforms.SerializableFunction;
+import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.collect.Ordering;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.joda.time.Instant;
+
+/**
+ * A class that manages the watermark for a Solace source.
+ *
+ * <p>The watermark is calculated based on the last saved watermark, the last update time, and the
+ * watermark idle duration threshold. If the last update time is before the watermark idle duration
+ * threshold, the watermark is set to the watermark idle duration threshold. Otherwise, the
+ * watermark is set to the last saved watermark.
+ *
+ * <p>The watermark is updated when a new record is received. The last saved watermark is set to the
+ * maximum of the current last saved watermark and the value resulting from the function calculating
+ * the timestamp from the record. The last update time is set to the current time when the watermark
+ * is updated.
+ */
+class WatermarkPolicy<T> implements Serializable {
+  private WatermarkParameters<T> watermarkParameters;
+
+  static <T> WatermarkPolicy<T> create(SerializableFunction<T, Instant> timestampFunction) {
+    return new WatermarkPolicy<T>(WatermarkParameters.<T>create(timestampFunction));
+  }
+
+  private WatermarkPolicy(WatermarkParameters<T> watermarkParameters) {
+    this.watermarkParameters = watermarkParameters;
+  }
+  /**
+   * Returns the current watermark.
+   *
+   * <p>The watermark is calculated based on the last saved watermark, the last update time, and the
+   * watermark idle duration threshold. If the last update time is before the watermark idle
+   * duration threshold, the watermark is set to the watermark idle duration threshold. Otherwise,
+   * the watermark is set to the last saved watermark.
+   *
+   * @return the current watermark
+   */
+  Instant getWatermark() {
+    Instant now = Instant.now();
+    Instant watermarkIdleThreshold =
+        now.minus(watermarkParameters.getWatermarkIdleDurationThreshold());
+
+    Instant newWatermark =
+        watermarkParameters.getLastUpdateTime().isBefore(watermarkIdleThreshold)
+            ? watermarkIdleThreshold
+            : watermarkParameters.getLastSavedWatermark();
+
+    if (newWatermark.isAfter(watermarkParameters.getCurrentWatermark())) {
+      watermarkParameters =
+          watermarkParameters.toBuilder().setCurrentWatermark(newWatermark).build();
+    }
+    return watermarkParameters.getCurrentWatermark();
+  }
+
+  /**
+   * Updates the watermark based on the provided record.
+   *
+   * <p>This method updates the last saved watermark and the last update time based on the timestamp
+   * function for the provided record. The last saved watermark is set to the maximum of the current
+   * last saved watermark and the timestamp of the record. The last update time is set to the
+   * current time.
+   *
+   * @param record The record to update the watermark with.
+   */
+  void update(@Nullable T record) {
+    if (record == null) {
+      return;
+    }
+    watermarkParameters =
+        watermarkParameters
+            .toBuilder()
+            .setLastSavedWatermark(
+                Ordering.natural()
+                    .max(
+                        watermarkParameters.getLastSavedWatermark(),
+                        watermarkParameters.getTimestampFn().apply(record)))
+            .setLastUpdateTime(Instant.now())
+            .build();
+  }
+}

sdks/java/io/solace/src/main/java/org/apache/beam/sdk/io/solace/read/package-info.java

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+/*
+ * 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.
+ */
+
+/** Solace IO connector - read connector classes. */
+package org.apache.beam.sdk.io.solace.read;