feat(agents): add ReActAgent (#2420)

Co-authored-by: dongzhancai1 <dongzhancai1@jd.com>

examples/agents/react_agent_example.py

@@ -0,0 +1,89 @@
+import asyncio
+import logging
+import os
+import sys
+
+from typing_extensions import Annotated, Doc
+
+from dbgpt.agent import AgentContext, AgentMemory, LLMConfig, UserProxyAgent
+from dbgpt.agent.expand.react_agent import ReActAgent
+from dbgpt.agent.resource import ToolPack, tool
+
+logging.basicConfig(
+    stream=sys.stdout,
+    level=logging.INFO,
+    format="%(asctime)s | %(levelname)s | %(name)s | %(message)s",
+)
+
+
+@tool
+def terminate(
+    final_answer: Annotated[str, Doc("final literal answer about the goal")],
+) -> str:
+    """When the goal achieved, this tool must be called."""
+    return final_answer
+
+
+@tool
+def simple_calculator(first_number: int, second_number: int, operator: str) -> float:
+    """Simple calculator tool. Just support +, -, *, /."""
+    if isinstance(first_number, str):
+        first_number = int(first_number)
+    if isinstance(second_number, str):
+        second_number = int(second_number)
+    if operator == "+":
+        return first_number + second_number
+    elif operator == "-":
+        return first_number - second_number
+    elif operator == "*":
+        return first_number * second_number
+    elif operator == "/":
+        return first_number / second_number
+    else:
+        raise ValueError(f"Invalid operator: {operator}")
+
+
+@tool
+def count_directory_files(path: Annotated[str, Doc("The directory path")]) -> int:
+    """Count the number of files in a directory."""
+    if not os.path.isdir(path):
+        raise ValueError(f"Invalid directory path: {path}")
+    return len(os.listdir(path))
+
+
+async def main():
+    from dbgpt.model.proxy.llms.siliconflow import SiliconFlowLLMClient
+
+    llm_client = SiliconFlowLLMClient(
+        model_alias="Qwen/Qwen2-7B-Instruct",
+    )
+    agent_memory = AgentMemory()
+    agent_memory.gpts_memory.init(conv_id="test456")
+
+    context: AgentContext = AgentContext(conv_id="test456", gpts_app_name="ReAct")
+
+    tools = ToolPack([simple_calculator, count_directory_files, terminate])
+
+    user_proxy = await UserProxyAgent().bind(agent_memory).bind(context).build()
+
+    tool_engineer = (
+        await ReActAgent(end_action_name="terminate", max_steps=10)
+        .bind(context)
+        .bind(LLMConfig(llm_client=llm_client))
+        .bind(agent_memory)
+        .bind(tools)
+        .build()
+    )
+
+    await user_proxy.initiate_chat(
+        recipient=tool_engineer,
+        reviewer=user_proxy,
+        message="Calculate the product of 10 and 99, Count the number of files in /tmp， answer in Chinese.",
+    )
+
+    # dbgpt-vis message infos
+    print(await agent_memory.gpts_memory.app_link_chat_message("test456"))
+
+
+if __name__ == "__main__":
+    asyncio.run(main())