Add cohere v2 default post process function

Signed-off-by: zane-neo <zaniu@amazon.com>

Author: zane-neo

common/src/main/java/org/opensearch/ml/common/connector/MLPostProcessFunction.java

@@ -17,6 +17,7 @@
 public class MLPostProcessFunction {
 
     public static final String COHERE_EMBEDDING = "connector.post_process.cohere.embedding";
+    public static final String COHERE_V2_EMBEDDING = "connector.post_process.cohere_v2.embedding";
     public static final String OPENAI_EMBEDDING = "connector.post_process.openai.embedding";
     public static final String BEDROCK_EMBEDDING = "connector.post_process.bedrock.embedding";
     public static final String BEDROCK_BATCH_JOB_ARN = "connector.post_process.bedrock.batch_job_arn";
@@ -35,13 +36,15 @@ public class MLPostProcessFunction {
         CohereRerankPostProcessFunction cohereRerankPostProcessFunction = new CohereRerankPostProcessFunction();
         JSON_PATH_EXPRESSION.put(OPENAI_EMBEDDING, "$.data[*].embedding");
         JSON_PATH_EXPRESSION.put(COHERE_EMBEDDING, "$.embeddings");
+        JSON_PATH_EXPRESSION.put(COHERE_V2_EMBEDDING, "$.embeddings.float");
         JSON_PATH_EXPRESSION.put(DEFAULT_EMBEDDING, "$[*]");
         JSON_PATH_EXPRESSION.put(BEDROCK_EMBEDDING, "$.embedding");
         JSON_PATH_EXPRESSION.put(BEDROCK_BATCH_JOB_ARN, "$");
         JSON_PATH_EXPRESSION.put(COHERE_RERANK, "$.results");
         JSON_PATH_EXPRESSION.put(DEFAULT_RERANK, "$[*]");
         POST_PROCESS_FUNCTIONS.put(OPENAI_EMBEDDING, embeddingPostProcessFunction);
         POST_PROCESS_FUNCTIONS.put(COHERE_EMBEDDING, embeddingPostProcessFunction);
+        POST_PROCESS_FUNCTIONS.put(COHERE_V2_EMBEDDING, embeddingPostProcessFunction);
         POST_PROCESS_FUNCTIONS.put(DEFAULT_EMBEDDING, embeddingPostProcessFunction);
         POST_PROCESS_FUNCTIONS.put(BEDROCK_EMBEDDING, bedrockEmbeddingPostProcessFunction);
         POST_PROCESS_FUNCTIONS.put(BEDROCK_BATCH_JOB_ARN, batchJobArnPostProcessFunction);

plugin/src/test/java/org/opensearch/ml/rest/RestBedRockInferenceIT.java

@@ -321,7 +321,7 @@ public void test_bedrockEmbeddingTypeSupportedModel_withDifferentResponseFilters
                 if (testCaseName.equals("response_filter_to_embedding_concrete_type")) {
                     assertEquals(errorMsg, 1024, ((List) ((Map<?, ?>) outputList.get(0)).get("data")).size());
                 } else {
-                    assertEquals(errorMsg, 1536, ((List) ((Map<?, ?>) outputList.get(0)).get("data")).size());
+                    assertEquals(errorMsg, 1024, ((List) ((Map<?, ?>) outputList.get(0)).get("data")).size());
                 }
             }
         }

plugin/src/test/resources/org/opensearch/ml/rest/templates/BedRockEmbeddingTypeSupportedConnectorBodies.json

@@ -100,7 +100,7 @@
     "parameters": {
       "region": "%s",
       "service_name": "bedrock",
-      "model_name": "amazon.titan-embed-text-v1"
+      "model_name": "amazon.titan-embed-text-v2:0"
     },
     "credential": {
       "access_key": "%s",