YueGuobin f688a2d5c0 feat(agent): enhance message handling with ID generation and format conversion
- Add message ID generation for initial HumanMessage creation
- Implement message converters for LangChain/OpenAI format interoperability
- Update documentation with detailed message format specifications
- Refactor AgentService to use centralized message conversion utilities
- Ensure tool_calls format compliance with OpenAI API standards
2026-03-04 23:05:43 +08:00

241 lines
7.4 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
#
# This file is part of GNS3 Server.
#
# GNS3 Server is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
"""
Message format converters for OpenAI-compatible message format.
Converts between LangChain messages and OpenAI-compatible format.
"""
import json
import uuid
from datetime import datetime
from typing import Dict, Any
def _ensure_string(content: Any) -> str:
"""Ensure content is a string, converting dicts/lists to JSON if needed."""
if isinstance(content, str):
return content
elif isinstance(content, (dict, list)):
return json.dumps(content, ensure_ascii=False, indent=2)
else:
return str(content)
def convert_langchain_to_openai(lc_message) -> Dict[str, Any]:
"""
Convert LangChain message to OpenAI-compatible format.
Args:
lc_message: LangChain message (HumanMessage, AIMessage, SystemMessage, ToolMessage)
Returns:
Dictionary in OpenAI-compatible format
"""
from langchain_core.messages import HumanMessage, AIMessage, SystemMessage, ToolMessage
# Generate message ID
msg_id = getattr(lc_message, 'id', None)
if msg_id is None:
msg_id = str(uuid.uuid4())
# Get timestamp
timestamp = getattr(lc_message, 'created_at', None)
if timestamp is None:
timestamp = datetime.utcnow().isoformat()
elif hasattr(timestamp, 'isoformat'):
timestamp = timestamp.isoformat()
# Base message structure
base_msg = {
"id": msg_id,
"created_at": timestamp,
"metadata": {}
}
# Convert based on message type
if isinstance(lc_message, HumanMessage):
return {
**base_msg,
"role": "user",
"content": lc_message.content
}
elif isinstance(lc_message, AIMessage):
msg = {
**base_msg,
"role": "assistant",
"content": lc_message.content
}
# Handle tool calls - convert to OpenAI format
if hasattr(lc_message, 'tool_calls') and lc_message.tool_calls:
tool_calls = []
for tc in lc_message.tool_calls:
# Convert to dict if it's an object
tc_dict = tc if isinstance(tc, dict) else tc.model_dump()
tool_calls.append({
"id": tc_dict.get("id", str(uuid.uuid4())),
"type": "function",
"function": {
"name": tc_dict.get("name", ""),
"arguments": tc_dict.get("args", {})
}
})
msg["tool_calls"] = tool_calls
return msg
elif isinstance(lc_message, ToolMessage):
return {
**base_msg,
"role": "tool",
"content": _ensure_string(lc_message.content),
"name": getattr(lc_message, 'name', ''),
"tool_call_id": getattr(lc_message, 'tool_call_id', '')
}
elif isinstance(lc_message, SystemMessage):
return {
**base_msg,
"role": "system",
"content": lc_message.content
}
else:
# Fallback for unknown message types
return {
**base_msg,
"role": "unknown",
"content": str(lc_message)
}
def convert_openai_to_langchain(msg: Dict[str, Any]):
"""
Convert OpenAI-compatible format to LangChain message.
Args:
msg: Dictionary in OpenAI-compatible format
Returns:
LangChain message
"""
from langchain_core.messages import HumanMessage, AIMessage, ToolMessage, SystemMessage
role = msg.get("role", "user")
content = msg.get("content", "")
if role == "user":
return HumanMessage(content=content, id=msg.get("id"))
elif role == "assistant":
ai_msg = AIMessage(content=content, id=msg.get("id"))
# Restore tool calls if present
if "tool_calls" in msg and msg["tool_calls"]:
tool_calls = []
for tc in msg["tool_calls"]:
tool_calls.append({
"id": tc.get("id", str(uuid.uuid4())),
"name": tc.get("function", {}).get("name", ""),
"args": tc.get("function", {}).get("arguments", {})
})
ai_msg.tool_calls = tool_calls
return ai_msg
elif role == "tool":
return ToolMessage(
content=content,
name=msg.get("name", ""),
tool_call_id=msg.get("tool_call_id", "")
)
elif role == "system":
return SystemMessage(content=content)
else:
# Fallback to HumanMessage for unknown roles
return HumanMessage(content=content)
def convert_stream_event_to_openai(event: Dict[str, Any]) -> Dict[str, Any]:
"""
Convert LangGraph streaming event to OpenAI-compatible format.
Args:
event: LangGraph streaming event
Returns:
Dictionary in OpenAI-compatible streaming response format
"""
event_type = event.get("event", "")
if event_type == "on_chat_model_stream":
chunk = event.get("data", {}).get("chunk", {})
content = getattr(chunk, 'content', '')
if content:
return {
"type": "content",
"content": content,
"message_id": event.get("metadata", {}).get("msg_id")
}
# Check for tool call chunks
if hasattr(chunk, 'tool_call_chunks') and chunk.tool_call_chunks:
for tc_chunk in chunk.tool_call_chunks:
tc_id = getattr(tc_chunk, 'id', None)
tc_name = getattr(tc_chunk, 'name', None)
tc_args = getattr(tc_chunk, 'args', None)
if tc_id:
return {
"type": "tool_call",
"tool_call": {
"id": tc_id,
"type": "function",
"function": {
"name": tc_name or "",
"arguments": tc_args or ""
}
}
}
elif event_type == "on_tool_start":
return {
"type": "tool_start",
"tool_name": event.get("name", ""),
"metadata": event.get("metadata", {})
}
elif event_type == "on_tool_end":
tool_output = event.get("data", {}).get("output", "")
# Convert dict or list output to JSON string for serialization
if isinstance(tool_output, (dict, list)):
tool_output = json.dumps(tool_output, ensure_ascii=False, indent=2)
return {
"type": "tool_end",
"tool_output": tool_output,
"tool_name": event.get("name", ""),
"metadata": event.get("metadata", {})
}
# Default empty response
return {"type": "unknown"}