Make ChangeStreamOptionsBuilder support startAtOperationTime

Closes spring-projects#3460

Author: tudormarc

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ChangeStreamOptions.java

@@ -40,6 +40,7 @@
  *
  * @author Christoph Strobl
  * @author Mark Paluch
+ * @author Tudor Marc
  * @since 2.1
  */
 public class ChangeStreamOptions {
@@ -49,6 +50,7 @@ public class ChangeStreamOptions {
 	private @Nullable FullDocument fullDocumentLookup;
 	private @Nullable Collation collation;
 	private @Nullable Object resumeTimestamp;
+	private @Nullable Object startAtOperationTime;
 	private Resume resume = Resume.UNDEFINED;
 
 	protected ChangeStreamOptions() {}
@@ -96,6 +98,20 @@ public Optional<BsonTimestamp> getResumeBsonTimestamp() {
 		return Optional.ofNullable(resumeTimestamp).map(timestamp -> asTimestampOfType(timestamp, BsonTimestamp.class));
 	}
 
+	/**
+	 * @return {@link Optional#empty()} if not set.
+	 */
+	public Optional<Instant> getStartAtOperationTime() {
+		return Optional.ofNullable(startAtOperationTime).map(timestamp -> asTimestampOfType(timestamp, Instant.class));
+	}
+
+	/**
+	 * @return {@link Optional#empty()} if not set.
+	 */
+	public Optional<BsonTimestamp> getStartAtOperationTimeBson() {
+		return Optional.ofNullable(startAtOperationTime).map(timestamp -> asTimestampOfType(timestamp, BsonTimestamp.class));
+	}
+
 	/**
 	 * @return {@literal true} if the change stream should be started after the {@link #getResumeToken() token}.
 	 * @since 2.2
@@ -176,6 +192,9 @@ public boolean equals(Object o) {
 		if (!ObjectUtils.nullSafeEquals(this.resumeTimestamp, that.resumeTimestamp)) {
 			return false;
 		}
+		if (!ObjectUtils.nullSafeEquals(this.startAtOperationTime, that.startAtOperationTime)) {
+			return false;
+		}
 		return resume == that.resume;
 	}
 
@@ -186,6 +205,7 @@ public int hashCode() {
 		result = 31 * result + ObjectUtils.nullSafeHashCode(fullDocumentLookup);
 		result = 31 * result + ObjectUtils.nullSafeHashCode(collation);
 		result = 31 * result + ObjectUtils.nullSafeHashCode(resumeTimestamp);
+		result = 31 * result + ObjectUtils.nullSafeHashCode(startAtOperationTime);
 		result = 31 * result + ObjectUtils.nullSafeHashCode(resume);
 		return result;
 	}
@@ -213,6 +233,7 @@ enum Resume {
 	 * Builder for creating {@link ChangeStreamOptions}.
 	 *
 	 * @author Christoph Strobl
+	 * @author Tudor Marc
 	 * @since 2.1
 	 */
 	public static class ChangeStreamOptionsBuilder {
@@ -222,6 +243,7 @@ public static class ChangeStreamOptionsBuilder {
 		private @Nullable FullDocument fullDocumentLookup;
 		private @Nullable Collation collation;
 		private @Nullable Object resumeTimestamp;
+		private @Nullable Object startAtOperationTime;
 		private Resume resume = Resume.UNDEFINED;
 
 		private ChangeStreamOptionsBuilder() {}
@@ -351,6 +373,34 @@ public ChangeStreamOptionsBuilder resumeAt(BsonTimestamp resumeTimestamp) {
 			return this;
 		}
 
+		/**
+		 * Set the cluster startAtOperationTime to open the cursor at a particular point in time.
+		 *
+		 * @param startAtOperationTime must not be {@literal null}.
+		 * @return this.
+		 */
+		public ChangeStreamOptionsBuilder startAtOperationTime(Instant startAtOperationTime) {
+
+			Assert.notNull(startAtOperationTime, "startAtOperationTime must not be null!");
+
+			this.startAtOperationTime = startAtOperationTime;
+			return this;
+		}
+
+		/**
+		 * Set the cluster startAtOperationTime to open the cursor at a particular point in time.
+		 *
+		 * @param startAtOperationTime must not be {@literal null}.
+		 * @return this.
+		 */
+		public ChangeStreamOptionsBuilder startAtOperationTime(BsonTimestamp startAtOperationTime) {
+
+			Assert.notNull(startAtOperationTime, "startAtOperationTime must not be null!");
+
+			this.startAtOperationTime = startAtOperationTime;
+			return this;
+		}
+
 		/**
 		 * Set the resume token after which to continue emitting notifications.
 		 *
@@ -393,6 +443,7 @@ public ChangeStreamOptions build() {
 			options.fullDocumentLookup = this.fullDocumentLookup;
 			options.collation = this.collation;
 			options.resumeTimestamp = this.resumeTimestamp;
+			options.startAtOperationTime = this.startAtOperationTime;
 			options.resume = this.resume;
 
 			return options;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/ReactiveChangeStreamOperationSupport.java

@@ -33,6 +33,7 @@
 
 /**
  * @author Christoph Strobl
+ * @author Tudor Marc
  * @since 2.2
  */
 class ReactiveChangeStreamOperationSupport implements ReactiveChangeStreamOperation {
@@ -178,6 +179,8 @@ private ChangeStreamOptionsBuilder initOptionsBuilder() {
 			} else {
 				options.getResumeTimestamp().ifPresent(builder::resumeAt);
 				options.getResumeBsonTimestamp().ifPresent(builder::resumeAt);
+				options.getStartAtOperationTime().ifPresent(builder::startAtOperationTime);
+				options.getStartAtOperationTimeBson().ifPresent(builder::startAtOperationTime);
 			}
 
 			return builder;

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/messaging/ChangeStreamRequest.java

@@ -232,6 +232,7 @@ public Duration maxAwaitTime() {
 	 * Builder for creating {@link ChangeStreamRequest}.
 	 *
 	 * @author Christoph Strobl
+	 * @author Tudor Marc
 	 * @since 2.1
 	 * @see ChangeStreamOptions
 	 */
@@ -409,6 +410,22 @@ public ChangeStreamRequestBuilder<T> startAfter(BsonValue resumeToken) {
 			return this;
 		}
 
+		/**
+		 * Set the cluster startAtOperationTime to open the cursor at a particular point in time.
+		 *
+		 * @param clusterTime must not be {@literal null}.
+		 * @return this.
+		 * @see ChangeStreamOptions#getStartAtOperationTime() ()
+		 * @see ChangeStreamOptionsBuilder#startAtOperationTime(java.time.Instant)
+		 */
+		public ChangeStreamRequestBuilder<T> startAtOperationTime(Instant clusterTime) {
+
+			Assert.notNull(clusterTime, "clusterTime must not be null!");
+			this.delegate.startAtOperationTime(clusterTime);
+
+			return this;
+		}
+
 		/**
 		 * Set the {@link FullDocument} lookup to {@link FullDocument#UPDATE_LOOKUP}.
 		 *

spring-data-mongodb/src/test/java/org/springframework/data/mongodb/core/ChangeStreamOptionsUnitTests.java

@@ -18,12 +18,14 @@
 import static org.assertj.core.api.Assertions.*;
 
 import org.bson.BsonDocument;
+import org.bson.BsonTimestamp;
 import org.junit.jupiter.api.Test;
 
 /**
  * Unit tests for {@link ChangeStreamOptions}.
  *
  * @author Mark Paluch
+ * @author Tudor Marc
  */
 public class ChangeStreamOptionsUnitTests {
 
@@ -53,4 +55,12 @@ public void shouldNotReportResumeStartAfter() {
 		assertThat(options.isResumeAfter()).isFalse();
 		assertThat(options.isStartAfter()).isFalse();
 	}
+
+	@Test // DATAMONGO-2607
+	public void shouldReportStartAtOperationTime() {
+
+		ChangeStreamOptions options = ChangeStreamOptions.builder().startAtOperationTime(new BsonTimestamp()).build();
+
+		assertThat(options.getStartAtOperationTime()).isNotNull();
+	}
 }