Fix: avoid ZSTD codec from overriding service codec factory. (#7037)

* Fix: enable ZSTD codec only if index.codec is set to ZSTD.

  - addresses #7012

Signed-off-by: Mulugeta Mammo <[email protected]>

* Removed custom CodecService and CodecServiceFactory classes.

  - Removed custom classes for CodecService and CodecServiceFactory.
  - Also removed PerFieldMappingPostingFormatCodec -- not required.
  - Added documentation.

Signed-off-by: Mulugeta Mammo <[email protected]>

* Bump zstd-jni version from 1.5.4-1 to 1.5.5-1.

  - Zstandard version 1.5.5 contains a bug fix for a rare corruption error
    described here: https://github.com/facebook/zstd/releases/tag/v1.5.5. The
    zstd-jni version we use here, 1.5.5-1, uses Zstandard v1.5.5.

Signed-off-by: Mulugeta Mammo <[email protected]>

---------

Signed-off-by: Mulugeta Mammo <[email protected]>

CHANGELOG.md

@@ -114,7 +114,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Bump `net.minidev:json-smart` from 2.4.7 to 2.4.10
 - Bump `org.apache.maven:maven-model` from 3.6.2 to 3.9.1
 - Bump `org.codehaus.jettison:jettison` from 1.5.3 to 1.5.4 ([#6878](https://github.com/opensearch-project/OpenSearch/pull/6878))
-- Add `com.github.luben:zstd-jni:1.5.4-1` ([#3577](https://github.com/opensearch-project/OpenSearch/pull/3577))
+- Add `com.github.luben:zstd-jni:1.5.5-1` ([#3577](https://github.com/opensearch-project/OpenSearch/pull/3577))
 - Bump: Netty from 4.1.90.Final to 4.1.91.Final , ASM 9.4 to ASM 9.5, ByteBuddy 1.14.2 to 1.14.3 ([#6981](https://github.com/opensearch-project/OpenSearch/pull/6981))
 - Bump `com.azure:azure-storage-blob` from 12.15.0 to 12.21.1
 

sandbox/plugins/custom-codecs/build.gradle

@@ -21,7 +21,7 @@ opensearchplugin {
 }
 
 dependencies {
-  api "com.github.luben:zstd-jni:1.5.4-1"
+  api "com.github.luben:zstd-jni:1.5.5-1"
 }
 
 yamlRestTest.enabled = false;

sandbox/plugins/custom-codecs/licenses/zstd-jni-1.5.5-1.jar.sha1

@@ -0,0 +1 @@
+fda1d6278299af27484e1cc3c79a060e41b7ef7e

sandbox/plugins/custom-codecs/src/main/java/org/opensearch/index/codec/customcodecs/CustomCodecPlugin.java

@@ -10,10 +10,6 @@
 
 import org.opensearch.plugins.Plugin;
 import org.opensearch.plugins.EnginePlugin;
-import org.opensearch.index.codec.CodecServiceFactory;
-import org.opensearch.index.IndexSettings;
-
-import java.util.Optional;
 
 /**
  * A plugin that implements custom codecs. Supports these codecs:
@@ -25,16 +21,6 @@
  * @opensearch.internal
  */
 public final class CustomCodecPlugin extends Plugin implements EnginePlugin {
-
-    /** Creates a new instance */
+    /** Creates a new instance. */
     public CustomCodecPlugin() {}
-
-    /**
-     * @param indexSettings is the default indexSettings
-     * @return the engine factory
-     */
-    @Override
-    public Optional<CodecServiceFactory> getCustomCodecServiceFactory(final IndexSettings indexSettings) {
-        return Optional.of(new CustomCodecServiceFactory());
-    }
 }

sandbox/plugins/custom-codecs/src/main/java/org/opensearch/index/codec/customcodecs/Lucene95CustomStoredFieldsFormat.java

@@ -61,6 +61,13 @@ public Lucene95CustomStoredFieldsFormat(Lucene95CustomCodec.Mode mode, int compr
         zstdNoDictCompressionMode = new ZstdNoDictCompressionMode(compressionLevel);
     }
 
+    /**
+      * Returns a {@link StoredFieldsReader} to load stored fields.
+      * @param directory The index directory.
+      * @param si The SegmentInfo that stores segment information.
+      * @param fn The fieldInfos.
+      * @param context The IOContext that holds additional details on the merge/search context.
+    */
     @Override
     public StoredFieldsReader fieldsReader(Directory directory, SegmentInfo si, FieldInfos fn, IOContext context) throws IOException {
         String value = si.getAttribute(MODE_KEY);
@@ -71,6 +78,12 @@ public StoredFieldsReader fieldsReader(Directory directory, SegmentInfo si, Fiel
         return impl(mode).fieldsReader(directory, si, fn, context);
     }
 
+    /**
+      * Returns a {@link StoredFieldsReader} to write stored fields.
+      * @param directory The index directory.
+      * @param si The SegmentInfo that stores segment information.
+      * @param context The IOContext that holds additional details on the merge/search context.
+    */
     @Override
     public StoredFieldsWriter fieldsWriter(Directory directory, SegmentInfo si, IOContext context) throws IOException {
         String previous = si.putAttribute(MODE_KEY, mode.name());

sandbox/plugins/custom-codecs/src/main/java/org/opensearch/index/codec/customcodecs/ZstdCodec.java

@@ -29,6 +29,7 @@ public ZstdCodec(int compressionLevel) {
         super(Mode.ZSTD, compressionLevel);
     }
 
+    /** The name for this codec. */
     @Override
     public String toString() {
         return getClass().getSimpleName();

sandbox/plugins/custom-codecs/src/main/java/org/opensearch/index/codec/customcodecs/ZstdCompressionMode.java

@@ -46,11 +46,13 @@ protected ZstdCompressionMode(int compressionLevel) {
         this.compressionLevel = compressionLevel;
     }
 
+    /** Creates a new compressor instance.*/
     @Override
     public Compressor newCompressor() {
         return new ZstdCompressor(compressionLevel);
     }
 
+    /** Creates a new decompressor instance. */
     @Override
     public Decompressor newDecompressor() {
         return new ZstdDecompressor();

sandbox/plugins/custom-codecs/src/main/java/org/opensearch/index/codec/customcodecs/ZstdNoDictCodec.java

@@ -29,6 +29,7 @@ public ZstdNoDictCodec(int compressionLevel) {
         super(Mode.ZSTDNODICT, compressionLevel);
     }
 
+    /** The name for this codec. */
     @Override
     public String toString() {
         return getClass().getSimpleName();

sandbox/plugins/custom-codecs/src/main/java/org/opensearch/index/codec/customcodecs/ZstdNoDictCompressionMode.java

@@ -41,11 +41,13 @@ protected ZstdNoDictCompressionMode(int compressionLevel) {
         this.compressionLevel = compressionLevel;
     }
 
+    /** Creates a new compressor instance.*/
     @Override
     public Compressor newCompressor() {
         return new ZstdCompressor(compressionLevel);
     }
 
+    /** Creates a new decompressor instance. */
     @Override
     public Decompressor newDecompressor() {
         return new ZstdDecompressor();