Feat: message manage (#12083)

### What problem does this PR solve?

Message CRUD.

Issue #4213 

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

common/settings.py

@@ -39,6 +39,9 @@ from rag.utils.oss_conn import RAGFlowOSS
 
 from rag.nlp import search
 
+import memory.utils.es_conn as memory_es_conn
+import memory.utils.infinity_conn as memory_infinity_conn
+
 LLM = None
 LLM_FACTORY = None
 LLM_BASE_URL = None
@@ -76,9 +79,11 @@ FEISHU_OAUTH = None
 OAUTH_CONFIG = None
 DOC_ENGINE = os.getenv('DOC_ENGINE', 'elasticsearch')
 DOC_ENGINE_INFINITY = (DOC_ENGINE.lower() == "infinity")
+MSG_ENGINE = DOC_ENGINE
 
 
 docStoreConn = None
+msgStoreConn = None
 
 retriever = None
 kg_retriever = None
@@ -256,6 +261,15 @@ def init_settings():
     else:
         raise Exception(f"Not supported doc engine: {DOC_ENGINE}")
 
+    global MSG_ENGINE, msgStoreConn
+    MSG_ENGINE = DOC_ENGINE  # use the same engine for message store
+    if MSG_ENGINE == "elasticsearch":
+        ES = get_base_config("es", {})
+        msgStoreConn = memory_es_conn.ESConnection()
+    elif MSG_ENGINE == "infinity":
+        INFINITY = get_base_config("infinity", {"uri": "infinity:23817"})
+        msgStoreConn = memory_infinity_conn.InfinityConnection()
+
     global AZURE, S3, MINIO, OSS, GCS
     if STORAGE_IMPL_TYPE in ['AZURE_SPN', 'AZURE_SAS']:
         AZURE = get_base_config("azure", {})