Add namespace type support to ChangeStreamDocument.

driver-core/src/main/com/mongodb/client/model/changestream/ChangeStreamDocument.java

@@ -46,6 +46,11 @@ public final class ChangeStreamDocument<TDocument> {
     @BsonId()
     private final BsonDocument resumeToken;
     private final BsonDocument namespaceDocument;
+
+    @BsonProperty("nsType")
+    private final String namespaceTypeString;
+    @BsonIgnore
+    private final NamespaceType namespaceType;
     private final BsonDocument destinationNamespaceDocument;
     private final TDocument fullDocument;
     private final TDocument fullDocumentBeforeChange;
@@ -66,9 +71,10 @@ public final class ChangeStreamDocument<TDocument> {
     /**
      * Creates a new instance
      *
-     * @param operationTypeString the operation type
+     * @param operationType the operation type
      * @param resumeToken the resume token
      * @param namespaceDocument the BsonDocument representing the namespace
+     * @param namespaceType the namespace type
      * @param destinationNamespaceDocument the BsonDocument representing the destinatation namespace
      * @param fullDocument the full document
      * @param fullDocumentBeforeChange the full document before change
@@ -85,9 +91,10 @@ public final class ChangeStreamDocument<TDocument> {
      */
     @BsonCreator
     public ChangeStreamDocument(
-            @Nullable @BsonProperty("operationType") final String operationTypeString,
+            @Nullable @BsonProperty("operationType") final String operationType,
             @BsonProperty("resumeToken") final BsonDocument resumeToken,
             @Nullable @BsonProperty("ns") final BsonDocument namespaceDocument,
+            @Nullable @BsonProperty("nsType") final String  namespaceType,
             @Nullable @BsonProperty("to") final BsonDocument destinationNamespaceDocument,
             @Nullable @BsonProperty("fullDocument") final TDocument fullDocument,
             @Nullable @BsonProperty("fullDocumentBeforeChange") final TDocument fullDocumentBeforeChange,
@@ -101,12 +108,14 @@ public ChangeStreamDocument(
             @Nullable @BsonProperty final BsonDocument extraElements) {
         this.resumeToken = resumeToken;
         this.namespaceDocument = namespaceDocument;
+        this.namespaceTypeString = namespaceType;
+        this.namespaceType = namespaceTypeString == null ? null : NamespaceType.fromString(namespaceType);
         this.destinationNamespaceDocument = destinationNamespaceDocument;
         this.fullDocumentBeforeChange = fullDocumentBeforeChange;
         this.documentKey = documentKey;
         this.fullDocument = fullDocument;
         this.clusterTime = clusterTime;
-        this.operationTypeString = operationTypeString;
+        this.operationTypeString = operationType;
         this.operationType = operationTypeString == null ? null : OperationType.fromString(operationTypeString);
         this.updateDescription = updateDescription;
         this.txnNumber = txnNumber;
@@ -134,6 +143,8 @@ public BsonDocument getResumeToken() {
      *
      * @return the namespace. If the namespaceDocument is null or if it is missing either the 'db' or 'coll' keys,
      * then this will return null.
+     * @see #getNamespaceType()
+     * @see #getNamespaceTypeString()
      */
     @BsonIgnore
     @Nullable
@@ -156,13 +167,49 @@ public MongoNamespace getNamespace() {
      *
      * @return the namespaceDocument
      * @since 3.8
+     * @see #getNamespaceType()
+     * @see #getNamespaceTypeString()
      */
     @BsonProperty("ns")
     @Nullable
     public BsonDocument getNamespaceDocument() {
         return namespaceDocument;
     }
 
+    /**
+     * Returns the type of the newly created namespace object as a String, derived from the "nsType" field in a change stream document.
+     * <p>
+     * This method is useful when using a driver release that has not yet been updated to include a newer namespace type in the
+     * {@link NamespaceType} enum.  In that case, {@link #getNamespaceType()} will return {@link NamespaceType#OTHER} and this method can
+     * be used to retrieve the actual namespace type as a string value.
+     * <p>
+     * May return null only if <code>$changeStreamSplitLargeEvent</code> is used.
+     *
+     * @return the namespace type as a string
+     * @since 5.6
+     * @mongodb.server.release 8.1
+     * @see #getNamespaceType()
+     * @see #getNamespaceDocument()
+     */
+    @Nullable
+    public String getNamespaceTypeString() {
+        return namespaceTypeString;
+    }
+
+    /**
+     * Returns the type of the newly created namespace object, derived from the "nsType" field in a change stream document.
+     *
+     * @return the namespace type.
+     * @since 5.6
+     * @mongodb.server.release 8.1
+     * @see #getNamespaceTypeString()
+     * @see #getNamespaceDocument()
+     */
+    @Nullable
+    public NamespaceType getNamespaceType() {
+        return namespaceType;
+    }
+
     /**
      * Returns the destination namespace, derived from the "to" field in a change stream document.
      *

driver-core/src/main/com/mongodb/client/model/changestream/NamespaceType.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2008-present MongoDB, Inc.
+ *
+ * Licensed 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 com.mongodb.client.model.changestream;
+
+import com.mongodb.lang.Nullable;
+
+/**
+ * Represents the type of the newly created namespace object in change stream events.
+ * <p>
+ * Only present for operations of type {@code create} and when the {@code showExpandedEvents}
+ * change stream option is enabled.
+ * </p>
+ *
+ * @since 5.6
+ * @mongodb.server.release 8.1
+ */
+public enum NamespaceType {
+    COLLECTION("collection"),
+    TIMESERIES("timeseries"),
+    VIEW("view"),
+    /**
+     * The other namespace type.
+     *
+     * <p>A placeholder for newer namespace types issued by the server.
+     * Users encountering OTHER namespace types are advised to update the driver to get the actual namespace type.</p>
+     *
+     * @since 5.6
+     */
+    OTHER("other");
+
+    private final String value;
+    NamespaceType(final String namespaceTypeName) {
+        this.value = namespaceTypeName;
+    }
+
+    /**
+     * @return the String representation of the namespace type
+     */
+    public String getValue() {
+        return value;
+    }
+
+    /**
+     * Returns the ChangeStreamNamespaceType from the string value.
+     *
+     * @param namespaceTypeName the string value.
+     * @return the namespace type.
+     */
+    public static NamespaceType fromString(@Nullable final String namespaceTypeName) {
+        if (namespaceTypeName != null) {
+            for (NamespaceType namespaceType : NamespaceType.values()) {
+                if (namespaceTypeName.equals(namespaceType.value)) {
+                    return namespaceType;
+                }
+            }
+        }
+        return OTHER;
+    }
+
+    @Override
+    public String toString() {
+        return "NamespaceType{"
+                + "value='" + value + "'"
+                + "}";
+    }
+}

driver-core/src/main/com/mongodb/client/model/changestream/OperationType.java

@@ -16,6 +16,8 @@
 
 package com.mongodb.client.model.changestream;
 
+import com.mongodb.lang.Nullable;
+
 /**
  * The {@code $changeStream} operation type.
  *
@@ -95,9 +97,9 @@ public String getValue() {
      * Returns the ChangeStreamOperationType from the string value.
      *
      * @param operationTypeName the string value.
-     * @return the read concern
+     * @return the operation type.
      */
-    public static OperationType fromString(final String operationTypeName) {
+    public static OperationType fromString(@Nullable final String operationTypeName) {
         if (operationTypeName != null) {
             for (OperationType operationType : OperationType.values()) {
                 if (operationTypeName.equals(operationType.value)) {

driver-core/src/test/unit/com/mongodb/client/model/changestream/ChangeStreamDocumentCodecSpecification.groovy

@@ -61,6 +61,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                 new ChangeStreamDocument<Document>(OperationType.INSERT.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         null,
                         Document.parse('{_id: 1, userName: "alice123", name: "Alice"}'),
                         null,
@@ -73,6 +74,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                 new ChangeStreamDocument<Document>(OperationType.UPDATE.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         null,
                         null,
                         null,
@@ -84,6 +86,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                 new ChangeStreamDocument<Document>(OperationType.UPDATE.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         null,
                         Document.parse('{_id: 1, userName: "alice123", name: "Alice"}'),
                         Document.parse('{_id: 1, userName: "alice1234", name: "Alice"}'),
@@ -96,6 +99,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                 new ChangeStreamDocument<Document>(OperationType.REPLACE.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         null,
                         Document.parse('{_id: 1, userName: "alice123", name: "Alice"}'),
                         Document.parse('{_id: 1, userName: "alice1234", name: "Alice"}'),
@@ -106,6 +110,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                 new ChangeStreamDocument<Document>(OperationType.DELETE.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         null,
                         null,
                         Document.parse('{_id: 1, userName: "alice123", name: "Alice"}'),
@@ -116,6 +121,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                 new ChangeStreamDocument<Document>(OperationType.DROP.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         null,
                         null,
                         null,
@@ -126,6 +132,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                 new ChangeStreamDocument<Document>(OperationType.RENAME.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         BsonDocument.parse('{db: "engineering", coll: "people"}'),
                         null,
                         null,
@@ -140,6 +147,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                         null,
                         null,
                         null,
+                        null,
                         new BsonTimestamp(1234, 2),
                         null, null, null, null, null, null
                 ),
@@ -150,12 +158,14 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
                         null,
                         null,
                         null,
+                        null,
                         new BsonTimestamp(1234, 2),
                         null, null, null, null, null, null
                 ),
                 new ChangeStreamDocument<Document>(OperationType.INSERT.value,
                         BsonDocument.parse('{token: true}'),
                         BsonDocument.parse('{db: "engineering", coll: "users"}'),
+                        NamespaceType.COLLECTION.value,
                         null,
                         Document.parse('{_id: 1, userName: "alice123", name: "Alice"}'),
                         null,
@@ -180,6 +190,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    },
+   nsType: 'collection',
    documentKey: {
       userName: 'alice123',
       _id: 1
@@ -204,6 +215,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    },
+   nsType: 'collection',
    documentKey: {
       _id: 1
    },
@@ -225,6 +237,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    },
+   nsType: 'collection',
    documentKey: {
       _id: 1
    },
@@ -261,6 +274,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    },
+   nsType: 'collection',
    documentKey: {
       _id: 1
    },
@@ -285,6 +299,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    },
+   nsType: 'collection',
    documentKey: {
       _id: 1
    },
@@ -304,6 +319,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    }
+   nsType: 'collection',
 }
 ''',
                 '''
@@ -315,6 +331,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    },
+   nsType: 'collection',
    to: {
       db: 'engineering',
       coll: 'people'
@@ -347,6 +364,7 @@ class ChangeStreamDocumentCodecSpecification extends Specification {
       db: 'engineering',
       coll: 'users'
    },
+   nsType: 'collection',
    documentKey: {
       userName: 'alice123',
       _id: 1