Feature (OpenMemory): Add support for LLM and Embedding Providers in OpenMemory (#2794)

openmemory/api/app/mcp_server.py

@@ -1,3 +1,20 @@
+"""
+MCP Server for OpenMemory with resilient memory client handling.
+
+This module implements an MCP (Model Context Protocol) server that provides
+memory operations for OpenMemory. The memory client is initialized lazily
+to prevent server crashes when external dependencies (like Ollama) are
+unavailable. If the memory client cannot be initialized, the server will
+continue running with limited functionality and appropriate error messages.
+
+Key features:
+- Lazy memory client initialization
+- Graceful error handling for unavailable dependencies
+- Fallback to database-only mode when vector store is unavailable
+- Proper logging for debugging connection issues
+- Environment variable parsing for API keys
+"""
+
 import logging
 import json
 from mcp.server.fastmcp import FastMCP
@@ -19,14 +36,17 @@ from qdrant_client import models as qdrant_models
 # Load environment variables
 load_dotenv()
 
-# Initialize MCP and memory client
+# Initialize MCP
 mcp = FastMCP("mem0-mcp-server")
 
-# Check if OpenAI API key is set
-if not os.getenv("OPENAI_API_KEY"):
-    raise Exception("OPENAI_API_KEY is not set in .env file")
-
-memory_client = get_memory_client()
+# Don't initialize memory client at import time - do it lazily when needed
+def get_memory_client_safe():
+    """Get memory client with error handling. Returns None if client cannot be initialized."""
+    try:
+        return get_memory_client()
+    except Exception as e:
+        logging.warning(f"Failed to get memory client: {e}")
+        return None
 
 # Context variables for user_id and client_name
 user_id_var: contextvars.ContextVar[str] = contextvars.ContextVar("user_id")
@@ -48,6 +68,11 @@ async def add_memories(text: str) -> str:
     if not client_name:
         return "Error: client_name not provided"
 
+    # Get memory client safely
+    memory_client = get_memory_client_safe()
+    if not memory_client:
+        return "Error: Memory system is currently unavailable. Please try again later."
+
     try:
         db = SessionLocal()
         try:
@@ -113,6 +138,7 @@ async def add_memories(text: str) -> str:
         finally:
             db.close()
     except Exception as e:
+        logging.exception(f"Error adding to memory: {e}")
         return f"Error adding to memory: {e}"
 
 
@@ -124,6 +150,12 @@ async def search_memory(query: str) -> str:
         return "Error: user_id not provided"
     if not client_name:
         return "Error: client_name not provided"
+
+    # Get memory client safely
+    memory_client = get_memory_client_safe()
+    if not memory_client:
+        return "Error: Memory system is currently unavailable. Please try again later."
+
     try:
         db = SessionLocal()
         try:
@@ -216,6 +248,12 @@ async def list_memories() -> str:
         return "Error: user_id not provided"
     if not client_name:
         return "Error: client_name not provided"
+
+    # Get memory client safely
+    memory_client = get_memory_client_safe()
+    if not memory_client:
+        return "Error: Memory system is currently unavailable. Please try again later."
+
     try:
         db = SessionLocal()
         try:
@@ -267,6 +305,7 @@ async def list_memories() -> str:
         finally:
             db.close()
     except Exception as e:
+        logging.exception(f"Error getting memories: {e}")
         return f"Error getting memories: {e}"
 
 
@@ -278,6 +317,12 @@ async def delete_all_memories() -> str:
         return "Error: user_id not provided"
     if not client_name:
         return "Error: client_name not provided"
+
+    # Get memory client safely
+    memory_client = get_memory_client_safe()
+    if not memory_client:
+        return "Error: Memory system is currently unavailable. Please try again later."
+
     try:
         db = SessionLocal()
         try:
@@ -289,7 +334,10 @@ async def delete_all_memories() -> str:
 
             # delete the accessible memories only
             for memory_id in accessible_memory_ids:
-                memory_client.delete(memory_id)
+                try:
+                    memory_client.delete(memory_id)
+                except Exception as delete_error:
+                    logging.warning(f"Failed to delete memory {memory_id} from vector store: {delete_error}")
 
             # Update each memory's state and create history entries
             now = datetime.datetime.now(datetime.UTC)
@@ -322,6 +370,7 @@ async def delete_all_memories() -> str:
         finally:
             db.close()
     except Exception as e:
+        logging.exception(f"Error deleting memories: {e}")
         return f"Error deleting memories: {e}"