diff --git a/server/src/main/java/org/opensearch/common/cache/tier/BytesReferenceSerializer.java b/server/src/main/java/org/opensearch/common/cache/tier/BytesReferenceSerializer.java new file mode 100644 index 0000000000000..3ac30b09bddca --- /dev/null +++ b/server/src/main/java/org/opensearch/common/cache/tier/BytesReferenceSerializer.java @@ -0,0 +1,42 @@ +/* + * SPDX-License-Identifier: Apache-2.0 + * + * The OpenSearch Contributors require contributions made to + * this file be licensed under the Apache-2.0 license or a + * compatible open source license. + */ + +package org.opensearch.common.cache.tier; + +import org.opensearch.core.common.bytes.BytesArray; +import org.opensearch.core.common.bytes.BytesReference; + +import java.util.Arrays; + +/** + * A serializer which transforms BytesReference to byte[]. + * The type of BytesReference is NOT preserved after deserialization, but nothing in opensearch should care. + */ +public class BytesReferenceSerializer implements Serializer { + // This class does not get passed to ehcache itself, so it's not required that classes match after deserialization. + + public BytesReferenceSerializer() {} + + @Override + public byte[] serialize(BytesReference object) { + return BytesReference.toBytes(object); + } + + @Override + public BytesReference deserialize(byte[] bytes) { + if (bytes == null) { + return null; + } + return new BytesArray(bytes); + } + + @Override + public boolean equals(BytesReference object, byte[] bytes) { + return Arrays.equals(serialize(object), bytes); + } +} diff --git a/server/src/test/java/org/opensearch/common/cache/tier/BytesReferenceSerializerTests.java b/server/src/test/java/org/opensearch/common/cache/tier/BytesReferenceSerializerTests.java new file mode 100644 index 0000000000000..af81f04149ae6 --- /dev/null +++ b/server/src/test/java/org/opensearch/common/cache/tier/BytesReferenceSerializerTests.java @@ -0,0 +1,67 @@ +/* + * SPDX-License-Identifier: Apache-2.0 + * + * The OpenSearch Contributors require contributions made to + * this file be licensed under the Apache-2.0 license or a + * compatible open source license. + */ + +package org.opensearch.common.cache.tier; + +import org.opensearch.common.Randomness; +import org.opensearch.common.bytes.ReleasableBytesReference; +import org.opensearch.common.util.BigArrays; +import org.opensearch.common.util.PageCacheRecycler; +import org.opensearch.core.common.bytes.BytesArray; +import org.opensearch.core.common.bytes.BytesReference; +import org.opensearch.core.common.bytes.CompositeBytesReference; +import org.opensearch.core.common.util.ByteArray; +import org.opensearch.test.OpenSearchTestCase; + +import java.util.Random; + +public class BytesReferenceSerializerTests extends OpenSearchTestCase { + public void testEquality() throws Exception { + BytesReferenceSerializer ser = new BytesReferenceSerializer(); + // Test that values are equal before and after serialization, for each implementation of BytesReference. + byte[] bytesValue = new byte[1000]; + Random rand = Randomness.get(); + rand.nextBytes(bytesValue); + + BytesReference ba = new BytesArray(bytesValue); + byte[] serialized = ser.serialize(ba); + assertTrue(ser.equals(ba, serialized)); + BytesReference deserialized = ser.deserialize(serialized); + assertEquals(ba, deserialized); + + ba = new BytesArray(new byte[] {}); + serialized = ser.serialize(ba); + assertTrue(ser.equals(ba, serialized)); + deserialized = ser.deserialize(serialized); + assertEquals(ba, deserialized); + + BytesReference cbr = CompositeBytesReference.of(new BytesArray(bytesValue), new BytesArray(bytesValue)); + serialized = ser.serialize(cbr); + assertTrue(ser.equals(cbr, serialized)); + deserialized = ser.deserialize(serialized); + assertEquals(cbr, deserialized); + + // We need the PagedBytesReference to be larger than the page size (16 KB) in order to actually create it + byte[] pbrValue = new byte[PageCacheRecycler.PAGE_SIZE_IN_BYTES * 2]; + rand.nextBytes(pbrValue); + ByteArray arr = BigArrays.NON_RECYCLING_INSTANCE.newByteArray(pbrValue.length); + arr.set(0L, pbrValue, 0, pbrValue.length); + assert !arr.hasArray(); + BytesReference pbr = BytesReference.fromByteArray(arr, pbrValue.length); + serialized = ser.serialize(pbr); + assertTrue(ser.equals(pbr, serialized)); + deserialized = ser.deserialize(serialized); + assertEquals(pbr, deserialized); + + BytesReference rbr = new ReleasableBytesReference(new BytesArray(bytesValue), ReleasableBytesReference.NO_OP); + serialized = ser.serialize(rbr); + assertTrue(ser.equals(rbr, serialized)); + deserialized = ser.deserialize(serialized); + assertEquals(rbr, deserialized); + } +}