Files
deer-flow/backend/packages/harness/deerflow/agents/middlewares/memory_middleware.py
T
Willem Jiang a55de566b9 refactor(backend): consolidate thread_id resolution into shared get_thread_id() utility (#2522)
Extract duplicated thread_id fallback logic from 11 files into a single
  deerflow.utils.runtime.get_thread_id() function with a documented 3-level
  cascade (runtime.context → runtime.config → get_config()).

  The module docstring also clarifies the __pregel_runtime injection pattern used in
  gateway mode.
2026-04-26 10:52:37 +08:00

96 lines
3.3 KiB
Python

"""Middleware for memory mechanism."""
import logging
from typing import override
from langchain.agents import AgentState
from langchain.agents.middleware import AgentMiddleware
from langgraph.runtime import Runtime
from deerflow.agents.memory.message_processing import detect_correction, detect_reinforcement, filter_messages_for_memory
from deerflow.agents.memory.queue import get_memory_queue
from deerflow.config.memory_config import get_memory_config
from deerflow.utils.runtime import get_thread_id
logger = logging.getLogger(__name__)
class MemoryMiddlewareState(AgentState):
"""Compatible with the `ThreadState` schema."""
pass
class MemoryMiddleware(AgentMiddleware[MemoryMiddlewareState]):
"""Middleware that queues conversation for memory update after agent execution.
This middleware:
1. After each agent execution, queues the conversation for memory update
2. Only includes user inputs and final assistant responses (ignores tool calls)
3. The queue uses debouncing to batch multiple updates together
4. Memory is updated asynchronously via LLM summarization
"""
state_schema = MemoryMiddlewareState
def __init__(self, agent_name: str | None = None):
"""Initialize the MemoryMiddleware.
Args:
agent_name: If provided, memory is stored per-agent. If None, uses global memory.
"""
super().__init__()
self._agent_name = agent_name
@override
def after_agent(self, state: MemoryMiddlewareState, runtime: Runtime) -> dict | None:
"""Queue conversation for memory update after agent completes.
Args:
state: The current agent state.
runtime: The runtime context.
Returns:
None (no state changes needed from this middleware).
"""
config = get_memory_config()
if not config.enabled:
return None
# Get thread ID from runtime context
thread_id = get_thread_id(runtime)
if not thread_id:
logger.debug("No thread_id in context, skipping memory update")
return None
# Get messages from state
messages = state.get("messages", [])
if not messages:
logger.debug("No messages in state, skipping memory update")
return None
# Filter to only keep user inputs and final assistant responses
filtered_messages = filter_messages_for_memory(messages)
# Only queue if there's meaningful conversation
# At minimum need one user message and one assistant response
user_messages = [m for m in filtered_messages if getattr(m, "type", None) == "human"]
assistant_messages = [m for m in filtered_messages if getattr(m, "type", None) == "ai"]
if not user_messages or not assistant_messages:
return None
# Queue the filtered conversation for memory update
correction_detected = detect_correction(filtered_messages)
reinforcement_detected = not correction_detected and detect_reinforcement(filtered_messages)
queue = get_memory_queue()
queue.add(
thread_id=thread_id,
messages=filtered_messages,
agent_name=self._agent_name,
correction_detected=correction_detected,
reinforcement_detected=reinforcement_detected,
)
return None