Introduce BsonUtil.mutableDeepCopy

bson/src/main/org/bson/internal/BsonUtil.java

@@ -0,0 +1,73 @@
+/*
+ * 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 org.bson.internal;
+
+import org.bson.BsonArray;
+import org.bson.BsonBinary;
+import org.bson.BsonDocument;
+import org.bson.BsonJavaScriptWithScope;
+import org.bson.BsonValue;
+
+/**
+ * <p>This class is not part of the public API and may be removed or changed at any time</p>
+ */
+public final class BsonUtil {
+    public static BsonDocument mutableDeepCopy(final BsonDocument original) {
+        BsonDocument copy = new BsonDocument(original.size());
+        original.forEach((key, value) -> copy.put(key, mutableDeepCopy(value)));
+        return copy;
+    }
+
+    private static BsonArray mutableDeepCopy(final BsonArray original) {
+        BsonArray copy = new BsonArray(original.size());
+        original.forEach(element -> copy.add(mutableDeepCopy(element)));
+        return copy;
+    }
+
+    private static BsonBinary mutableDeepCopy(final BsonBinary original) {
+        return new BsonBinary(original.getType(), original.getData().clone());
+    }
+
+    private static BsonJavaScriptWithScope mutableDeepCopy(final BsonJavaScriptWithScope original) {
+        return new BsonJavaScriptWithScope(original.getCode(), mutableDeepCopy(original.getScope()));
+    }
+
+    private static <T extends BsonValue> T mutableDeepCopy(final T original) {
+        BsonValue copy;
+        switch (original.getBsonType()) {
+            case DOCUMENT:
+                copy = mutableDeepCopy(original.asDocument());
+                break;
+            case ARRAY:
+                copy = mutableDeepCopy(original.asArray());
+                break;
+            case BINARY:
+                copy = mutableDeepCopy(original.asBinary());
+                break;
+            case JAVASCRIPT_WITH_SCOPE:
+                copy = mutableDeepCopy(original.asJavaScriptWithScope());
+                break;
+            default:
+                copy = original;
+        }
+        @SuppressWarnings("unchecked")
+        T result = (T) copy;
+        return result;
+    }
+
+    private BsonUtil() {
+    }
+}

bson/src/test/unit/org/bson/internal/BsonUtilTest.java

@@ -0,0 +1,131 @@
+/*
+ * 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 org.bson.internal;
+
+import org.bson.BsonArray;
+import org.bson.BsonBinary;
+import org.bson.BsonDocument;
+import org.bson.BsonDocumentWrapper;
+import org.bson.BsonJavaScriptWithScope;
+import org.bson.BsonValue;
+import org.bson.RawBsonArray;
+import org.bson.RawBsonDocument;
+import org.bson.conversions.Bson;
+import org.junit.jupiter.api.Test;
+
+import java.nio.charset.StandardCharsets;
+import java.util.AbstractMap.SimpleImmutableEntry;
+import java.util.Map.Entry;
+
+import static java.util.Arrays.asList;
+import static java.util.Collections.singletonList;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotSame;
+
+final class BsonUtilTest {
+    @Test
+    public void mutableDeepCopy() {
+        Entry<String, BsonBinary> originalBsonBinaryEntry = new SimpleImmutableEntry<>(
+                "bsonBinary",
+                new BsonBinary("bsonBinary".getBytes(StandardCharsets.UTF_8))
+        );
+        Entry<String, BsonJavaScriptWithScope> originalBsonJavaScriptWithScopeEntry = new SimpleImmutableEntry<>(
+                "bsonJavaScriptWithScopeEntry",
+                new BsonJavaScriptWithScope("\"use strict\";", new BsonDocument())
+        );
+        Entry<String, RawBsonDocument> originalRawBsonDocumentEntry = new SimpleImmutableEntry<>(
+                "rawBsonDocument",
+                RawBsonDocument.parse("{rawBsonDocument: 'rawBsonDocument_value'}")
+        );
+        Entry<String, BsonDocumentWrapper<RawBsonDocument>> originalBsonDocumentWrapperEntry = new SimpleImmutableEntry<>(
+                "bsonDocumentWrapper",
+                new BsonDocumentWrapper<>(originalRawBsonDocumentEntry.getValue(), Bson.DEFAULT_CODEC_REGISTRY.get(RawBsonDocument.class))
+        );
+        Entry<String, BsonDocument> originalBsonDocumentEntry = new SimpleImmutableEntry<>(
+                "bsonDocument",
+                new BsonDocument()
+                        .append(originalBsonBinaryEntry.getKey(), originalBsonBinaryEntry.getValue())
+                        .append(originalBsonJavaScriptWithScopeEntry.getKey(), originalBsonJavaScriptWithScopeEntry.getValue())
+                        .append(originalRawBsonDocumentEntry.getKey(), originalRawBsonDocumentEntry.getValue())
+                        .append(originalBsonDocumentWrapperEntry.getKey(), originalBsonDocumentWrapperEntry.getValue())
+        );
+        Entry<String, BsonArray> originalBsonArrayEntry = new SimpleImmutableEntry<>(
+                "bsonArray",
+                new BsonArray(singletonList(new BsonArray()))
+        );
+        Entry<String, RawBsonArray> originalRawBsonArrayEntry = new SimpleImmutableEntry<>(
+                "rawBsonArray",
+                rawBsonArray(
+                        originalBsonBinaryEntry.getValue(),
+                        originalBsonJavaScriptWithScopeEntry.getValue(),
+                        originalRawBsonDocumentEntry.getValue(),
+                        originalBsonDocumentWrapperEntry.getValue(),
+                        originalBsonDocumentEntry.getValue(),
+                        originalBsonArrayEntry.getValue())
+        );
+        BsonDocument original = new BsonDocument()
+                .append(originalBsonBinaryEntry.getKey(), originalBsonBinaryEntry.getValue())
+                .append(originalBsonJavaScriptWithScopeEntry.getKey(), originalBsonJavaScriptWithScopeEntry.getValue())
+                .append(originalRawBsonDocumentEntry.getKey(), originalRawBsonDocumentEntry.getValue())
+                .append(originalBsonDocumentWrapperEntry.getKey(), originalBsonDocumentWrapperEntry.getValue())
+                .append(originalBsonDocumentEntry.getKey(), originalBsonDocumentEntry.getValue())
+                .append(originalBsonArrayEntry.getKey(), originalBsonArrayEntry.getValue())
+                .append(originalRawBsonArrayEntry.getKey(), originalRawBsonArrayEntry.getValue());
+        BsonDocument copy = BsonUtil.mutableDeepCopy(original);
+        assertEqualNotSameAndMutable(original, copy);
+        original.forEach((key, value) -> assertEqualNotSameAndMutable(value, copy.get(key)));
+        // check nested document
+        String nestedDocumentKey = originalBsonDocumentEntry.getKey();
+        BsonDocument originalNestedDocument = original.getDocument(nestedDocumentKey);
+        BsonDocument copyNestedDocument = copy.getDocument(nestedDocumentKey);
+        assertEqualNotSameAndMutable(originalNestedDocument, copyNestedDocument);
+        originalNestedDocument.forEach((key, value) -> assertEqualNotSameAndMutable(value, copyNestedDocument.get(key)));
+        // check nested array
+        String nestedArrayKey = originalRawBsonArrayEntry.getKey();
+        BsonArray originalNestedArray = original.getArray(nestedArrayKey);
+        BsonArray copyNestedArray = copy.getArray(nestedArrayKey);
+        assertEqualNotSameAndMutable(originalNestedArray, copyNestedArray);
+        for (int i = 0; i < originalNestedArray.size(); i++) {
+            assertEqualNotSameAndMutable(originalNestedArray.get(i), copyNestedArray.get(i));
+        }
+    }
+
+    private static RawBsonArray rawBsonArray(final BsonValue... elements) {
+        return (RawBsonArray) new RawBsonDocument(
+                new BsonDocument("a", new BsonArray(asList(elements))), Bson.DEFAULT_CODEC_REGISTRY.get(BsonDocument.class))
+                .get("a");
+    }
+
+    private static void assertEqualNotSameAndMutable(final Object expected, final Object actual) {
+        assertEquals(expected, actual);
+        assertNotSame(expected, actual);
+        Class<?> actualClass = actual.getClass();
+        if (expected instanceof BsonDocument) {
+            assertEquals(BsonDocument.class, actualClass);
+        } else if (expected instanceof BsonArray) {
+            assertEquals(BsonArray.class, actualClass);
+        } else if (expected instanceof BsonBinary) {
+            assertEquals(BsonBinary.class, actualClass);
+        } else if (expected instanceof BsonJavaScriptWithScope) {
+            assertEquals(BsonJavaScriptWithScope.class, actualClass);
+        } else {
+            org.bson.assertions.Assertions.fail("Unexpected " + expected.getClass().toString());
+        }
+    }
+
+    private BsonUtilTest() {
+    }
+}

driver-core/src/main/com/mongodb/internal/client/model/AbstractConstructibleBson.java

@@ -27,6 +27,8 @@
 import java.util.Optional;
 import java.util.function.Consumer;
 
+import static org.bson.internal.BsonUtil.mutableDeepCopy;
+
 /**
  * A {@link Bson} that allows constructing new instances via {@link #newAppended(String, Object)} instead of mutating {@code this}.
  * See {@link #AbstractConstructibleBson(Bson, Document)} for the note on mutability.
@@ -141,7 +143,7 @@ public String toString() {
     }
 
     static BsonDocument newMerged(final BsonDocument base, final BsonDocument appended) {
-        BsonDocument result = base.clone();
+        BsonDocument result = mutableDeepCopy(base);
         result.putAll(appended);
         return result;
     }

driver-reactive-streams/src/main/com/mongodb/reactivestreams/client/internal/vault/ClientEncryptionImpl.java

@@ -63,6 +63,7 @@
 import static java.lang.String.format;
 import static java.util.Arrays.asList;
 import static java.util.Collections.singletonList;
+import static org.bson.internal.BsonUtil.mutableDeepCopy;
 
 /**
  * <p>This class is not part of the public API and may be removed or changed at any time</p>
@@ -223,7 +224,7 @@ public Publisher<BsonDocument> createEncryptedCollection(final MongoDatabase dat
             return Mono.defer(() -> {
                 // `Mono.defer` results in `maybeUpdatedEncryptedFields` and `dataKeyMightBeCreated` (mutable state)
                 // being created once per `Subscriber`, which allows the produced `Mono` to support multiple `Subscribers`.
-                BsonDocument maybeUpdatedEncryptedFields = encryptedFields.clone();
+                BsonDocument maybeUpdatedEncryptedFields = mutableDeepCopy(encryptedFields);
                 AtomicBoolean dataKeyMightBeCreated = new AtomicBoolean();
                 Iterable<Mono<BsonDocument>> publishersOfUpdatedFields = () -> maybeUpdatedEncryptedFields.get("fields").asArray()
                         .stream()

driver-sync/src/main/com/mongodb/client/internal/ClientEncryptionImpl.java

@@ -58,6 +58,7 @@
 import static java.lang.String.format;
 import static java.util.Arrays.asList;
 import static java.util.Collections.singletonList;
+import static org.bson.internal.BsonUtil.mutableDeepCopy;
 
 /**
  * <p>This class is not part of the public API and may be removed or changed at any time</p>
@@ -207,7 +208,7 @@ public BsonDocument createEncryptedCollection(final MongoDatabase database, fina
                 dataKeyOptions.masterKey(masterKey);
             }
             String keyIdBsonKey = "keyId";
-            BsonDocument maybeUpdatedEncryptedFields = encryptedFields.clone();
+            BsonDocument maybeUpdatedEncryptedFields = mutableDeepCopy(encryptedFields);
             // only the mutability of `dataKeyMightBeCreated` is important, it does not need to be thread-safe
             AtomicBoolean dataKeyMightBeCreated = new AtomicBoolean();
             try {