Adding tests

Signed-off-by: Bharathwaj G <[email protected]>

server/src/main/resources/META-INF/services/org.apache.lucene.codecs.Codec

@@ -0,0 +1 @@
+org.opensearch.index.codec.composite.Composite99Codec

server/src/test/java/org/opensearch/index/codec/CodecTests.java

@@ -48,6 +48,7 @@
 import org.opensearch.env.Environment;
 import org.opensearch.index.IndexSettings;
 import org.opensearch.index.analysis.IndexAnalyzers;
+import org.opensearch.index.codec.composite.Composite99Codec;
 import org.opensearch.index.engine.EngineConfig;
 import org.opensearch.index.mapper.MapperService;
 import org.opensearch.index.similarity.SimilarityService;
@@ -59,6 +60,8 @@
 import java.io.IOException;
 import java.util.Collections;
 
+import org.mockito.Mockito;
+
 import static org.opensearch.index.engine.EngineConfig.INDEX_CODEC_COMPRESSION_LEVEL_SETTING;
 import static org.hamcrest.Matchers.instanceOf;
 
@@ -93,6 +96,35 @@ public void testZlib() throws Exception {
         assert codec instanceof PerFieldMappingPostingFormatCodec;
     }
 
+    public void testResolveDefaultCodecsWithCompositeIndex() throws Exception {
+        CodecService codecService = createCodecService(false, true);
+        assertThat(codecService.codec("default"), instanceOf(Composite99Codec.class));
+    }
+
+    public void testDefaultWithCompositeIndex() throws Exception {
+        Codec codec = createCodecService(false, true).codec("default");
+        assertStoredFieldsCompressionEquals(Lucene99Codec.Mode.BEST_SPEED, codec);
+        assert codec instanceof Composite99Codec;
+    }
+
+    public void testBestCompressionWithCompositeIndex() throws Exception {
+        Codec codec = createCodecService(false, true).codec("best_compression");
+        assertStoredFieldsCompressionEquals(Lucene99Codec.Mode.BEST_COMPRESSION, codec);
+        assert codec instanceof Composite99Codec;
+    }
+
+    public void testLZ4WithCompositeIndex() throws Exception {
+        Codec codec = createCodecService(false, true).codec("lz4");
+        assertStoredFieldsCompressionEquals(Lucene99Codec.Mode.BEST_SPEED, codec);
+        assert codec instanceof Composite99Codec;
+    }
+
+    public void testZlibWithCompositeIndex() throws Exception {
+        Codec codec = createCodecService(false, true).codec("zlib");
+        assertStoredFieldsCompressionEquals(Lucene99Codec.Mode.BEST_COMPRESSION, codec);
+        assert codec instanceof Composite99Codec;
+    }
+
     public void testBestCompressionWithCompressionLevel() {
         final Settings settings = Settings.builder()
             .put(INDEX_CODEC_COMPRESSION_LEVEL_SETTING.getKey(), randomIntBetween(1, 6))
@@ -150,10 +182,17 @@ private void assertStoredFieldsCompressionEquals(Lucene99Codec.Mode expected, Co
     }
 
     private CodecService createCodecService(boolean isMapperServiceNull) throws IOException {
+        return createCodecService(isMapperServiceNull, false);
+    }
+
+    private CodecService createCodecService(boolean isMapperServiceNull, boolean isCompositeIndexPresent) throws IOException {
         Settings nodeSettings = Settings.builder().put(Environment.PATH_HOME_SETTING.getKey(), createTempDir()).build();
         if (isMapperServiceNull) {
             return new CodecService(null, IndexSettingsModule.newIndexSettings("_na", nodeSettings), LogManager.getLogger("test"));
         }
+        if (isCompositeIndexPresent) {
+            return buildCodecServiceWithCompositeIndex(nodeSettings);
+        }
         return buildCodecService(nodeSettings);
     }
 
@@ -176,6 +215,14 @@ private CodecService buildCodecService(Settings nodeSettings) throws IOException
         return new CodecService(service, indexSettings, LogManager.getLogger("test"));
     }
 
+    private CodecService buildCodecServiceWithCompositeIndex(Settings nodeSettings) throws IOException {
+
+        IndexSettings indexSettings = IndexSettingsModule.newIndexSettings("_na", nodeSettings);
+        MapperService service = Mockito.mock(MapperService.class);
+        Mockito.when(service.isCompositeIndexPresent()).thenReturn(true);
+        return new CodecService(service, indexSettings, LogManager.getLogger("test"));
+    }
+
     private SegmentReader getSegmentReader(Codec codec) throws IOException {
         Directory dir = newDirectory();
         IndexWriterConfig iwc = newIndexWriterConfig(null);