tj9dZddlmZddlZddlZddlZddlmZmZddl m Z ddl m Z ddl mZmZmZmZmZddlmZmZmZmZerdd lmZmZdd lmZdd lmZdd lmZGd deeeeefZ dS)z!Tool retry middleware for agents.) annotationsN) TYPE_CHECKINGAny) ToolMessage) GraphBubbleUp) OnFailureRetryOncalculate_delayshould_retry_exceptionvalidate_retry_params)AgentMiddleware AgentStateContextT ResponseT) AwaitableCallable)Command)ToolCallRequest)BaseToolc reZdZdZddefdddddd d.fdZd/dZed0d!Zd1d%Z d2d+Z d3d-Z xZ S)4ToolRetryMiddlewarea Middleware that automatically retries failed tool calls with configurable backoff. Supports retrying on specific exceptions and exponential backoff. Examples: !!! example "Basic usage with default settings (2 retries, exponential backoff)" ```python from langchain.agents import create_agent from langchain.agents.middleware import ToolRetryMiddleware agent = create_agent(model, tools=[search_tool], middleware=[ToolRetryMiddleware()]) ``` !!! example "Retry specific exceptions only" ```python from requests.exceptions import RequestException, Timeout retry = ToolRetryMiddleware( max_retries=4, retry_on=(RequestException, Timeout), backoff_factor=1.5, ) ``` !!! example "Custom exception filtering" ```python from requests.exceptions import HTTPError def should_retry(exc: Exception) -> bool: # Only retry on 5xx errors if isinstance(exc, HTTPError): return 500 <= exc.status_code < 600 return False retry = ToolRetryMiddleware( max_retries=3, retry_on=should_retry, ) ``` !!! example "Apply to specific tools with custom error handling" ```python def format_error(exc: Exception) -> str: return "Database temporarily unavailable. Please try again later." retry = ToolRetryMiddleware( max_retries=4, tools=["search_database"], on_failure=format_error, ) ``` !!! example "Apply to specific tools using `BaseTool` instances" ```python from langchain_core.tools import tool @tool def search_database(query: str) -> str: '''Search the database.''' return results retry = ToolRetryMiddleware( max_retries=4, tools=[search_database], # Pass BaseTool instance ) ``` !!! example "Constant backoff (no exponential growth)" ```python retry = ToolRetryMiddleware( max_retries=5, backoff_factor=0.0, # No exponential growth initial_delay=2.0, # Always wait 2 seconds ) ``` !!! example "Raise exception on failure" ```python retry = ToolRetryMiddleware( max_retries=2, on_failure="error", # Re-raise exception instead of returning message ) ``` Ncontinueg@g?gN@T) max_retriestoolsretry_on on_failurebackoff_factor initial_delay max_delayjitterrintrlist[BaseTool | str] | Nonerr rrrfloatrr r!boolreturnNonectt|||||dkr!d} tj| t dd}n&|dkr d} tj| t dd}||_||d |D|_nd |_g|_||_ ||_ ||_ ||_ ||_ ||_d S) uvInitialize `ToolRetryMiddleware`. Args: max_retries: Maximum number of retry attempts after the initial call. Must be `>= 0`. tools: Optional list of tools or tool names to apply retry logic to. Can be a list of `BaseTool` instances or tool name strings. If `None`, applies to all tools. retry_on: Either a tuple of exception types to retry on, or a callable that takes an exception and returns `True` if it should be retried. Default is to retry on all exceptions. on_failure: Behavior when all retries are exhausted. Options: - `'continue'`: Return a `ToolMessage` with error details, allowing the LLM to handle the failure and potentially recover. - `'error'`: Re-raise the exception, stopping agent execution. - **Custom callable:** Function that takes the exception and returns a string for the `ToolMessage` content, allowing custom error formatting. **Deprecated values** (for backwards compatibility): - `'return_message'`: Use `'continue'` instead. - `'raise'`: Use `'error'` instead. backoff_factor: Multiplier for exponential backoff. Each retry waits `initial_delay * (backoff_factor ** retry_number)` seconds. Set to `0.0` for constant delay. initial_delay: Initial delay in seconds before first retry. max_delay: Maximum delay in seconds between retries. Caps exponential backoff growth. jitter: Whether to add random jitter (`±25%`) to delay to avoid thundering herd. Raises: ValueError: If `max_retries < 0` or delays are negative. raisezion_failure='raise' is deprecated and will be removed in a future version. Use on_failure='error' instead.r) stacklevelerrorreturn_messagezuon_failure='return_message' is deprecated and will be removed in a future version. Use on_failure='continue' instead.rNcJg|] }t|ts|jn|!S) isinstancestrname).0tools d/var/www/html/CA-Chatbot/venv/lib/python3.11/site-packages/langchain/agents/middleware/tool_retry.py z0ToolRetryMiddleware.__init__..s. d d dVZ*T32G2G!QT d d d)super__init__r warningswarnDeprecationWarningr _tool_filterrrrrrr r!) selfrrrrrrr r!msg __class__s r4r8zToolRetryMiddleware.__init__sr  k=)^TTT  2  M#1a @ @ @ @ JJ + + +J  M#1a @ @ @ @#J& +   d d^c d d dD   $D    $,*" r6 tool_namer0c&|jdS||jvS)zCheck if retry logic should apply to this tool. Args: tool_name: Name of the tool being called. Returns: `True` if retry logic should apply, `False` otherwise. NT)r<)r=r@s r4_should_retry_toolz&ToolRetryMiddleware._should_retry_tools    $4D---r6exc Exception attempts_madec t|j}t|}|dkrdnd}d|d|d|d|d|d S) a6Format the failure message when retries are exhausted. Args: tool_name: Name of the tool that failed. exc: The exception that caused the failure. attempts_made: Number of attempts actually made. Returns: Formatted error message string. attemptattemptszTool 'z' failed after  z with z: z. Please try again.)type__name__r0)r@rCrEexc_typeexc_msg attempt_words r4_format_failure_messagez+ToolRetryMiddleware._format_failure_messages}99%c(($1Q$6$6yyJ  =Y = =} = =| = = = = ' = = = r6 tool_call_id str | Nonerc|jdkr|t|jr||}n||||}t|||dS)aHandle failure when all retries are exhausted. Args: tool_name: Name of the tool that failed. tool_call_id: ID of the tool call (may be `None`). exc: The exception that caused the failure. attempts_made: Number of attempts actually made. Returns: `ToolMessage` with error details. Raises: Exception: If `on_failure` is `'error'`, re-raises the exception. r+)contentrQr1status)rcallablerPr)r=r@rQrCrErTs r4_handle_failurez#ToolRetryMiddleware._handle_failuresv" ?g % %I DO $ $ Rooc**GG229c=QQG%     r6requestrhandler7Callable[[ToolCallRequest], ToolMessage | Command[Any]]ToolMessage | Command[Any]c ^|jr |jjn |jd}||s ||S|jd}t |jdzD]} ||cS#t $rt$r}|dz}t||j s||jkrCt||j |j |j |j}|dkrtj|n|||||cYd}~cSYd}~d}~wwxYwd} t%| )aIntercept tool execution and retry on failure. Args: request: Tool call request with call dict, `BaseTool`, state, and runtime. handler: Callable to execute the tool (can be called multiple times). Returns: `ToolMessage` or `Command` (the final result). Raises: RuntimeError: If the retry loop completes without returning. This should not happen. r1idrGrrr r!rN2Unexpected: retry loop completed without returning)r3r1 tool_callrBrangerrrDr rr rrr r!timesleeprW RuntimeError r=rXrYr@rQrHrCrEdelayr>s r4wrap_tool_callz"ToolRetryMiddleware.wrap_tool_call!s"*1TGL%%7;LV;T &&y11 $77## #(. T-122 ] ]G ]ww'''''     ] ] ] '! .c4=AAT---+'+':&*&8"&.#{ Eqyy 5))) // <m\\\\\\\\\\/ ]4C3s( A55D BD DDBCallable[[ToolCallRequest], Awaitable[ToolMessage | Command[Any]]]c K|jr |jjn |jd}||s||d{VS|jd}t |jdzD]} ||d{VcS#t $rt$r}|dz}t||j s||jkrIt||j |j |j |j}|dkrtj|d{Vn|||||cYd}~cSYd}~d}~wwxYwd} t%| )aIntercept and control async tool execution with retry logic. Args: request: Tool call request with call `dict`, `BaseTool`, state, and runtime. handler: Async callable to execute the tool and returns `ToolMessage` or `Command`. Returns: `ToolMessage` or `Command` (the final result). Raises: RuntimeError: If the retry loop completes without returning. This should not happen. r1Nr]rGr^rr_)r3r1r`rBrarrrDr rr rrr r!asynciorcrWrdres r4awrap_tool_callz#ToolRetryMiddleware.awrap_tool_call_s"*1TGL%%7;LV;T &&y11 * )))))))) )(. T-122 ] ]G ]$WW-----------     ] ] ] '! .c4=AAT---+'+':&*&8"&.#{ Eqyy%mE222222222 // <m\\\\\\\\\\/ ]4C3s0BD/BD*D/*D/)rr"rr#rr rrrr$rr$r r$r!r%r&r')r@r0r&r%)r@r0rCrDrEr"r&r0) r@r0rQrRrCrDrEr"r&r)rXrrYrZr&r[)rXrrYrhr&r[) rL __module__ __qualname____doc__rDr8rB staticmethodrPrWrgrk __classcell__)r?s@r4rrs__H-1&L * #"]]]]]]]]~ . . . .   \ &    @< < < < |< < < < < < < < r6r)!rn __future__rrjrbr9typingrrlangchain_core.messagesrlanggraph.errorsr"langchain.agents.middleware._retryrr r r r !langchain.agents.middleware.typesr rrrcollections.abcrrlanggraph.typesrrlangchain.toolsrrr.r6r4rzs''"""""" %%%%%%%%//////******_^^^^^^^^^^^)33333333''''''AAAAAA((((((| | | | | /*Y*?9*TU| | | | | r6