Refactor Compressors from CompressorFactory to CompressorRegistry for extensibility (opensearch-project#9262)

* Refactor Compressors from CompressorFactory to CompressorRegistry for extensibility

This commit refactors the CompressorFactory static singleton
class and CompressorType enum to a formal CompressorRegistry and enables
downstream implementations to register their own compression
implementations for use in compressing Blob stores and MediaType data.
This is different from Lucene's Codec compression extension points which
expose different compression implementations for Lucene's Stored Fields.

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

* fix missing javadoc and relocate the common compress to compress package

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

* fix deprecated case

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

* fix typo in compress build.gradle

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

* PR cleanup

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

* PR changes

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

* update with initial annotations

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

* remove NONE singleton in CompressorRegistry and remove static block init

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>

---------

Signed-off-by: Nicholas Walter Knize <nknize@apache.org>
Signed-off-by: Kiran Reddy <kkreddy@amazon.com>

Author: nknize

gradle/missing-javadoc.gradle

@@ -166,6 +166,7 @@ configure([
 configure([
   project(":libs:opensearch-common"),
   project(":libs:opensearch-core"),
+  project(":libs:opensearch-compress"),
   project(":plugins:events-correlation-engine"),
   project(":server")
 ]) {

libs/compress/build.gradle

@@ -0,0 +1,38 @@
+/*
+ * 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.
+ *
+ * Modifications Copyright OpenSearch Contributors. See
+ * GitHub history for details.
+ */
+
+apply plugin: 'opensearch.build'
+apply plugin: 'opensearch.publish'
+
+base {
+  archivesName = 'opensearch-compress'
+}
+
+dependencies {
+  api project(':libs:opensearch-common')
+  api project(':libs:opensearch-core')
+
+  //zstd
+  api "com.github.luben:zstd-jni:${versions.zstd}"
+
+  testImplementation(project(":test:framework")) {
+    // tests use the locally compiled version of server
+    exclude group: 'org.opensearch', module: 'opensearch-compress'
+  }
+}
+
+tasks.named('forbiddenApisMain').configure {
+  // :libs:opensearch-compress does not depend on server
+  // TODO: Need to decide how we want to handle for forbidden signatures with the changes to server
+  replaceSignatureFiles 'jdk-signatures'
+}
+
+jarHell.enabled = false

server/licenses/zstd-jni-1.5.5-3.jar.sha1 renamed to libs/compress/licenses/zstd-jni-1.5.5-3.jar.sha1

@@ -6,13 +6,14 @@
  * compatible open source license.
  */
 
-package org.opensearch.common.compress;
+package org.opensearch.compress;
 
 import com.github.luben.zstd.RecyclingBufferPool;
 import com.github.luben.zstd.ZstdInputStreamNoFinalizer;
 import com.github.luben.zstd.ZstdOutputStreamNoFinalizer;
+import org.opensearch.common.annotation.PublicApi;
 import org.opensearch.core.common.bytes.BytesReference;
-import org.opensearch.core.common.compress.Compressor;
+import org.opensearch.core.compress.Compressor;
 
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
@@ -24,7 +25,8 @@
 /**
  * {@link Compressor} implementation based on the ZSTD compression algorithm.
  *
- * @opensearch.internal
+ * @opensearch.api - registered name requires BWC support
+ * @opensearch.experimental - class methods might change
  */
 public class ZstdCompressor implements Compressor {
     // An arbitrary header that we use to identify compressed streams
@@ -33,6 +35,14 @@ public class ZstdCompressor implements Compressor {
     // a XContent
     private static final byte[] HEADER = new byte[] { 'Z', 'S', 'T', 'D', '\0' };
 
+    /**
+     * The name to register the compressor by
+     *
+     * @opensearch.api - requires BWC support
+     */
+    @PublicApi(since = "2.10.0")
+    public static final String NAME = "ZSTD";
+
     private static final int LEVEL = 3;
 
     private static final int BUFFER_SIZE = 4096;

server/licenses/zstd-jni-LICENSE.txt renamed to libs/compress/licenses/zstd-jni-LICENSE.txt

@@ -6,5 +6,7 @@
  * compatible open source license.
  */
 
-/** Classes for core compress module */
-package org.opensearch.core.common.compress;
+/**
+ * Concrete {@link org.opensearch.core.compress.Compressor} implementations
+ */
+package org.opensearch.compress;

server/licenses/zstd-jni-NOTICE.txt renamed to libs/compress/licenses/zstd-jni-NOTICE.txt

@@ -0,0 +1,32 @@
+/*
+ * 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.compress.spi;
+
+import org.opensearch.compress.ZstdCompressor;
+import org.opensearch.core.compress.Compressor;
+import org.opensearch.core.compress.spi.CompressorProvider;
+
+import java.util.AbstractMap.SimpleEntry;
+import java.util.Map.Entry;
+import java.util.List;
+
+/**
+ * Additional "optional" compressor implementations provided by the opensearch compress library
+ *
+ * @opensearch.internal
+ */
+public class CompressionProvider implements CompressorProvider {
+
+    /** Returns the concrete {@link Compressor}s provided by the compress library */
+    @SuppressWarnings({ "unchecked", "rawtypes" })
+    @Override
+    public List<Entry<String, Compressor>> getCompressors() {
+        return List.of(new SimpleEntry<>(ZstdCompressor.NAME, new ZstdCompressor()));
+    }
+}

server/src/main/java/org/opensearch/common/compress/ZstdCompressor.java renamed to libs/compress/src/main/java/org/opensearch/compress/ZstdCompressor.java

@@ -0,0 +1,15 @@
+/*
+ * 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.
+ */
+
+/**
+ * Service Provider Interface for registering concrete {@link org.opensearch.core.compress.Compressor}
+ * implementations.
+ *
+ * See {@link org.opensearch.compress.ZstdCompressor}
+ */
+package org.opensearch.compress.spi;

libs/core/src/main/java/org/opensearch/core/common/compress/package-info.java renamed to libs/compress/src/main/java/org/opensearch/compress/package-info.java

@@ -0,0 +1,13 @@
+/*
+ * 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.
+ */
+
+/**
+ * This is the compress library for registering optional
+ * {@link org.opensearch.core.compress.Compressor} implementations
+ */
+package org.opensearch;