chore: remove Langchain tools import (#3407)

api/core/rag/retrieval/output_parser/react_output.py

@@ -0,0 +1,25 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from typing import NamedTuple, Union
+
+
+@dataclass
+class ReactAction:
+    """A full description of an action for an ReactAction to execute."""
+
+    tool: str
+    """The name of the Tool to execute."""
+    tool_input: Union[str, dict]
+    """The input to pass in to the Tool."""
+    log: str
+    """Additional information to log about the action."""
+
+
+class ReactFinish(NamedTuple):
+    """The final return value of an ReactFinish."""
+
+    return_values: dict
+    """Dictionary of return values."""
+    log: str
+    """Additional information to log about the return value"""

api/core/rag/retrieval/output_parser/structured_chat.py

@@ -2,28 +2,24 @@ import json
 import re
 from typing import Union
 
-from langchain.agents.structured_chat.output_parser import StructuredChatOutputParser as LCStructuredChatOutputParser
-from langchain.agents.structured_chat.output_parser import logger
-from langchain.schema import AgentAction, AgentFinish, OutputParserException
+from core.rag.retrieval.output_parser.react_output import ReactAction, ReactFinish
 
 
-class StructuredChatOutputParser(LCStructuredChatOutputParser):
-    def parse(self, text: str) -> Union[AgentAction, AgentFinish]:
+class StructuredChatOutputParser:
+    def parse(self, text: str) -> Union[ReactAction, ReactFinish]:
         try:
             action_match = re.search(r"```(\w*)\n?({.*?)```", text, re.DOTALL)
             if action_match is not None:
                 response = json.loads(action_match.group(2).strip(), strict=False)
                 if isinstance(response, list):
-                    # gpt turbo frequently ignores the directive to emit a single action
-                    logger.warning("Got multiple action responses: %s", response)
                     response = response[0]
                 if response["action"] == "Final Answer":
-                    return AgentFinish({"output": response["action_input"]}, text)
+                    return ReactFinish({"output": response["action_input"]}, text)
                 else:
-                    return AgentAction(
+                    return ReactAction(
                         response["action"], response.get("action_input", {}), text
                     )
             else:
-                return AgentFinish({"output": text}, text)
+                return ReactFinish({"output": text}, text)
         except Exception as e:
-            raise OutputParserException(f"Could not parse LLM output: {text}")
+            raise ValueError(f"Could not parse LLM output: {text}")