src/backend/base/langflow/api/v1/endpoints.py

from __future__ import annotations

import asyncio
import time
from http import HTTPStatus
from typing import TYPE_CHECKING, Annotated
from uuid import UUID

import sqlalchemy as sa
from fastapi import (
    APIRouter,
    BackgroundTasks,
    Body,
    Depends,
    HTTPException,
    Request,
    UploadFile,
    status,
)
from loguru import logger
from sqlmodel import select

from langflow.api.utils import CurrentActiveUser, DbSession, parse_value
from langflow.api.v1.schemas import (
    ConfigResponse,
    CustomComponentRequest,
    CustomComponentResponse,
    InputValueRequest,
    RunResponse,
    SimplifiedAPIRequest,
    TaskStatusResponse,
    UpdateCustomComponentRequest,
    UploadFileResponse,
)
from langflow.custom.custom_component.component import Component
from langflow.custom.utils import build_custom_component_template, get_instance_name
from langflow.exceptions.api import APIException, InvalidChatInputError
from langflow.graph.graph.base import Graph
from langflow.graph.schema import RunOutputs
from langflow.helpers.flow import get_flow_by_id_or_endpoint_name
from langflow.helpers.user import get_user_by_flow_id_or_endpoint_name
from langflow.interface.initialize.loading import update_params_with_load_from_db_fields
from langflow.processing.process import process_tweaks, run_graph_internal
from langflow.schema.graph import Tweaks
from langflow.services.auth.utils import api_key_security, get_current_active_user
from langflow.services.cache.utils import save_uploaded_file
from langflow.services.database.models.flow import Flow
from langflow.services.database.models.flow.model import FlowRead
from langflow.services.database.models.flow.utils import (
    get_all_webhook_components_in_flow,
)
from langflow.services.database.models.user.model import User, UserRead
from langflow.services.deps import get_session_service, get_settings_service, get_task_service, get_telemetry_service
from langflow.services.settings.feature_flags import FEATURE_FLAGS
from langflow.services.telemetry.schema import RunPayload
from langflow.utils.version import get_version_info

if TYPE_CHECKING:
    from langflow.services.settings.service import SettingsService

router = APIRouter(tags=["Base"])


@router.get("/all", dependencies=[Depends(get_current_active_user)])
async def get_all():
    from langflow.interface.types import get_and_cache_all_types_dict

    try:
        return await get_and_cache_all_types_dict(settings_service=get_settings_service())

    except Exception as exc:
        raise HTTPException(status_code=500, detail=str(exc)) from exc


def validate_input_and_tweaks(input_request: SimplifiedAPIRequest) -> None:
    # If the input_value is not None and the input_type is "chat"
    # then we need to check the tweaks if the ChatInput component is present
    # and if its input_value is not None
    # if so, we raise an error
    if input_request.tweaks is None:
        return
    for key, value in input_request.tweaks.items():
        if "ChatInput" in key or "Chat Input" in key:
            if isinstance(value, dict):
                has_input_value = value.get("input_value") is not None
                input_value_is_chat = input_request.input_value is not None and input_request.input_type == "chat"
                if has_input_value and input_value_is_chat:
                    msg = "If you pass an input_value to the chat input, you cannot pass a tweak with the same name."
                    raise InvalidChatInputError(msg)
        elif ("Text Input" in key or "TextInput" in key) and isinstance(value, dict):
            has_input_value = value.get("input_value") is not None
            input_value_is_text = input_request.input_value is not None and input_request.input_type == "text"
            if has_input_value and input_value_is_text:
                msg = "If you pass an input_value to the text input, you cannot pass a tweak with the same name."
                raise InvalidChatInputError(msg)


async def simple_run_flow(
    flow: Flow,
    input_request: SimplifiedAPIRequest,
    *,
    stream: bool = False,
    api_key_user: User | None = None,
):
    if input_request.input_value is not None and input_request.tweaks is not None:
        validate_input_and_tweaks(input_request)
    try:
        task_result: list[RunOutputs] = []
        user_id = api_key_user.id if api_key_user else None
        flow_id_str = str(flow.id)
        if flow.data is None:
            msg = f"Flow {flow_id_str} has no data"
            raise ValueError(msg)
        graph_data = flow.data.copy()
        graph_data = process_tweaks(graph_data, input_request.tweaks or {}, stream=stream)
        graph = Graph.from_payload(graph_data, flow_id=flow_id_str, user_id=str(user_id), flow_name=flow.name)
        inputs = [
            InputValueRequest(
                components=[],
                input_value=input_request.input_value,
                type=input_request.input_type,
            )
        ]
        if input_request.output_component:
            outputs = [input_request.output_component]
        else:
            outputs = [
                vertex.id
                for vertex in graph.vertices
                if input_request.output_type == "debug"
                or (
                    vertex.is_output
                    and (input_request.output_type == "any" or input_request.output_type in vertex.id.lower())  # type: ignore[operator]
                )
            ]
        task_result, session_id = await run_graph_internal(
            graph=graph,
            flow_id=flow_id_str,
            session_id=input_request.session_id,
            inputs=inputs,
            outputs=outputs,
            stream=stream,
        )

        return RunResponse(outputs=task_result, session_id=session_id)

    except sa.exc.StatementError as exc:
        raise ValueError(str(exc)) from exc


async def simple_run_flow_task(
    flow: Flow,
    input_request: SimplifiedAPIRequest,
    *,
    stream: bool = False,
    api_key_user: User | None = None,
):
    """Run a flow task as a BackgroundTask, therefore it should not throw exceptions."""
    try:
        return await simple_run_flow(
            flow=flow,
            input_request=input_request,
            stream=stream,
            api_key_user=api_key_user,
        )

    except Exception:  # noqa: BLE001
        logger.exception(f"Error running flow {flow.id} task")


@router.post("/run/{flow_id_or_name}", response_model_exclude_none=True)  # noqa: RUF100, FAST003
async def simplified_run_flow(
    *,
    background_tasks: BackgroundTasks,
    flow: Annotated[FlowRead | None, Depends(get_flow_by_id_or_endpoint_name)],
    input_request: SimplifiedAPIRequest | None = None,
    stream: bool = False,
    api_key_user: Annotated[UserRead, Depends(api_key_security)],
) -> RunResponse:
    """Executes a specified flow by ID.

    Executes a specified flow by ID with input customization, performance enhancements through caching,
    and optional data streaming.

    ### Parameters:
    - `db` (Session): Database session for executing queries.
    - `flow_id_or_name` (str): ID or endpoint name of the flow to run.
    - `input_request` (SimplifiedAPIRequest): Request object containing input values, types, output selection, tweaks,
      and session ID.
    - `api_key_user` (User): User object derived from the provided API key, used for authentication.
    - `session_service` (SessionService): Service for managing flow sessions, essential for session reuse and caching.

    ### SimplifiedAPIRequest:
    - `input_value` (Optional[str], default=""): Input value to pass to the flow.
    - `input_type` (Optional[Literal["chat", "text", "any"]], default="chat"): Type of the input value,
      determining how the input is interpreted.
    - `output_type` (Optional[Literal["chat", "text", "any", "debug"]], default="chat"): Desired type of output,
      affecting which components' outputs are included in the response. If set to "debug", all outputs are returned.
    - `output_component` (Optional[str], default=None): Specific component output to retrieve. If provided,
      only the output of the specified component is returned. This overrides the `output_type` parameter.
    - `tweaks` (Optional[Tweaks], default=None): Adjustments to the flow's behavior, allowing for custom execution
      parameters.
    - `session_id` (Optional[str], default=None): An identifier for reusing session data, aiding in performance for
      subsequent requests.


    ### Tweaks
    A dictionary of tweaks to customize the flow execution.
    The tweaks can be used to modify the flow's parameters and components.
    Tweaks can be overridden by the input values.
    You can use Component's `id` or Display Name as key to tweak a specific component
    (e.g., `{"Component Name": {"parameter_name": "value"}}`).
    You can also use the parameter name as key to tweak all components with that parameter
    (e.g., `{"parameter_name": "value"}`).

    ### Returns:
    - A `RunResponse` object containing the execution results, including selected (or all, based on `output_type`)
      outputs of the flow and the session ID, facilitating result retrieval and further interactions in a session
      context.

    ### Raises:
    - HTTPException: 404 if the specified flow ID curl -X 'POST' \

    ### Example:
    ```bash
    curl -X 'POST' \
      'http://<your_server>/run/{flow_id}' \
      -H 'accept: application/json' \
      -H 'Content-Type: application/json' \
      -H 'x-api-key: YOU_API_KEY' \
      -H '
      -d '{
            "input_value": "Sample input",
            "input_type": "chat",
            "output_type": "chat",
            "tweaks": {},
          }'
    ```

    This endpoint provides a powerful interface for executing flows with enhanced flexibility and efficiency,
    supporting a wide range of applications by allowing for dynamic input and output configuration along with
    performance optimizations through session management and caching.
    """
    telemetry_service = get_telemetry_service()
    input_request = input_request if input_request is not None else SimplifiedAPIRequest()
    if flow is None:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Flow not found")
    start_time = time.perf_counter()
    try:
        result = await simple_run_flow(
            flow=flow,
            input_request=input_request,
            stream=stream,
            api_key_user=api_key_user,
        )
        end_time = time.perf_counter()
        background_tasks.add_task(
            telemetry_service.log_package_run,
            RunPayload(
                run_is_webhook=False,
                run_seconds=int(end_time - start_time),
                run_success=True,
                run_error_message="",
            ),
        )

    except ValueError as exc:
        background_tasks.add_task(
            telemetry_service.log_package_run,
            RunPayload(
                run_is_webhook=False,
                run_seconds=int(time.perf_counter() - start_time),
                run_success=False,
                run_error_message=str(exc),
            ),
        )
        if "badly formed hexadecimal UUID string" in str(exc):
            # This means the Flow ID is not a valid UUID which means it can't find the flow
            raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(exc)) from exc
        if "not found" in str(exc):
            raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(exc)) from exc
        raise APIException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, exception=exc, flow=flow) from exc
    except InvalidChatInputError as exc:
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(exc)) from exc
    except Exception as exc:
        background_tasks.add_task(
            telemetry_service.log_package_run,
            RunPayload(
                run_is_webhook=False,
                run_seconds=int(time.perf_counter() - start_time),
                run_success=False,
                run_error_message=str(exc),
            ),
        )
        raise APIException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, exception=exc, flow=flow) from exc

    return result


@router.post("/webhook/{flow_id_or_name}", response_model=dict, status_code=HTTPStatus.ACCEPTED)  # noqa: RUF100, FAST003
async def webhook_run_flow(
    flow: Annotated[Flow, Depends(get_flow_by_id_or_endpoint_name)],
    user: Annotated[User, Depends(get_user_by_flow_id_or_endpoint_name)],
    request: Request,
    background_tasks: BackgroundTasks,
):
    """Run a flow using a webhook request.

    Args:
        flow (Flow, optional): The flow to be executed. Defaults to Depends(get_flow_by_id).
        user (User): The flow user.
        request (Request): The incoming HTTP request.
        background_tasks (BackgroundTasks): The background tasks manager.

    Returns:
        dict: A dictionary containing the status of the task.

    Raises:
        HTTPException: If the flow is not found or if there is an error processing the request.
    """
    telemetry_service = get_telemetry_service()
    start_time = time.perf_counter()
    logger.debug("Received webhook request")
    error_msg = ""
    try:
        try:
            data = await request.body()
        except Exception as exc:
            error_msg = str(exc)
            raise HTTPException(status_code=500, detail=error_msg) from exc

        if not data:
            error_msg = "Request body is empty. You should provide a JSON payload containing the flow ID."
            raise HTTPException(status_code=400, detail=error_msg)

        try:
            # get all webhook components in the flow
            webhook_components = get_all_webhook_components_in_flow(flow.data)
            tweaks = {}

            for component in webhook_components:
                tweaks[component["id"]] = {"data": data.decode() if isinstance(data, bytes) else data}
            input_request = SimplifiedAPIRequest(
                input_value="",
                input_type="chat",
                output_type="chat",
                tweaks=tweaks,
                session_id=None,
            )

            logger.debug("Starting background task")
            background_tasks.add_task(
                simple_run_flow_task,
                flow=flow,
                input_request=input_request,
                api_key_user=user,
            )
        except Exception as exc:
            error_msg = str(exc)
            raise HTTPException(status_code=500, detail=error_msg) from exc
    finally:
        background_tasks.add_task(
            telemetry_service.log_package_run,
            RunPayload(
                run_is_webhook=True,
                run_seconds=int(time.perf_counter() - start_time),
                run_success=not error_msg,
                run_error_message=error_msg,
            ),
        )

    return {"message": "Task started in the background", "status": "in progress"}


@router.post(
    "/run/advanced/{flow_id}",
    response_model=RunResponse,
    response_model_exclude_none=True,
)
async def experimental_run_flow(
    *,
    session: DbSession,
    flow_id: UUID,
    inputs: list[InputValueRequest] | None = None,
    outputs: list[str] | None = None,
    tweaks: Annotated[Tweaks | None, Body(embed=True)] = None,
    stream: Annotated[bool, Body(embed=True)] = False,
    session_id: Annotated[None | str, Body(embed=True)] = None,
    api_key_user: Annotated[UserRead, Depends(api_key_security)],
) -> RunResponse:
    """Executes a specified flow by ID with optional input values, output selection, tweaks, and streaming capability.

    This endpoint supports running flows with caching to enhance performance and efficiency.

    ### Parameters:
    - `flow_id` (str): The unique identifier of the flow to be executed.
    - `inputs` (List[InputValueRequest], optional): A list of inputs specifying the input values and components
      for the flow. Each input can target specific components and provide custom values.
    - `outputs` (List[str], optional): A list of output names to retrieve from the executed flow.
      If not provided, all outputs are returned.
    - `tweaks` (Optional[Tweaks], optional): A dictionary of tweaks to customize the flow execution.
      The tweaks can be used to modify the flow's parameters and components.
      Tweaks can be overridden by the input values.
    - `stream` (bool, optional): Specifies whether the results should be streamed. Defaults to False.
    - `session_id` (Union[None, str], optional): An optional session ID to utilize existing session data for the flow
      execution.
    - `api_key_user` (User): The user associated with the current API key. Automatically resolved from the API key.

    ### Returns:
    A `RunResponse` object containing the selected outputs (or all if not specified) of the executed flow
    and the session ID.
    The structure of the response accommodates multiple inputs, providing a nested list of outputs for each input.

    ### Raises:
    HTTPException: Indicates issues with finding the specified flow, invalid input formats, or internal errors during
    flow execution.

    ### Example usage:
    ```json
    POST /run/{flow_id}
    x-api-key: YOUR_API_KEY
    Payload:
    {
        "inputs": [
            {"components": ["component1"], "input_value": "value1"},
            {"components": ["component3"], "input_value": "value2"}
        ],
        "outputs": ["Component Name", "component_id"],
        "tweaks": {"parameter_name": "value", "Component Name": {"parameter_name": "value"}, "component_id": {"parameter_name": "value"}}
        "stream": false
    }
    ```

    This endpoint facilitates complex flow executions with customized inputs, outputs, and configurations,
    catering to diverse application requirements.
    """  # noqa: E501
    session_service = get_session_service()
    flow_id_str = str(flow_id)
    if outputs is None:
        outputs = []
    if inputs is None:
        inputs = [InputValueRequest(components=[], input_value="")]

    if session_id:
        try:
            session_data = await session_service.load_session(session_id, flow_id=flow_id_str)
        except Exception as exc:
            raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=str(exc)) from exc
        graph, _artifacts = session_data or (None, None)
        if graph is None:
            msg = f"Session {session_id} not found"
            raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=msg)
    else:
        try:
            # Get the flow that matches the flow_id and belongs to the user
            # flow = session.query(Flow).filter(Flow.id == flow_id).filter(Flow.user_id == api_key_user.id).first()
            stmt = select(Flow).where(Flow.id == flow_id_str).where(Flow.user_id == api_key_user.id)
            flow = (await session.exec(stmt)).first()
        except sa.exc.StatementError as exc:
            # StatementError('(builtins.ValueError) badly formed hexadecimal UUID string')
            if "badly formed hexadecimal UUID string" in str(exc):
                logger.error(f"Flow ID {flow_id_str} is not a valid UUID")
                # This means the Flow ID is not a valid UUID which means it can't find the flow
                raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(exc)) from exc
            raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=str(exc)) from exc
        except Exception as exc:
            raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=str(exc)) from exc

        if flow is None:
            msg = f"Flow {flow_id_str} not found"
            raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=msg)

        if flow.data is None:
            msg = f"Flow {flow_id_str} has no data"
            raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=msg)
        try:
            graph_data = flow.data
            graph_data = process_tweaks(graph_data, tweaks or {})
            graph = Graph.from_payload(graph_data, flow_id=flow_id_str)
        except Exception as exc:
            raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=str(exc)) from exc

    try:
        task_result, session_id = await run_graph_internal(
            graph=graph,
            flow_id=flow_id_str,
            session_id=session_id,
            inputs=inputs,
            outputs=outputs,
            stream=stream,
        )
    except Exception as exc:
        raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail=str(exc)) from exc

    return RunResponse(outputs=task_result, session_id=session_id)


@router.post(
    "/predict/{flow_id}",
    dependencies=[Depends(api_key_security)],
)
@router.post(
    "/process/{flow_id}",
    dependencies=[Depends(api_key_security)],
)
async def process() -> None:
    """Endpoint to process an input with a given flow_id."""
    # Raise a depreciation warning
    logger.warning(
        "The /process endpoint is deprecated and will be removed in a future version. Please use /run instead."
    )
    raise HTTPException(
        status_code=status.HTTP_400_BAD_REQUEST,
        detail="The /process endpoint is deprecated and will be removed in a future version. "
        "Please use /run instead.",
    )


@router.get("/task/{task_id}")
async def get_task_status(task_id: str) -> TaskStatusResponse:
    task_service = get_task_service()
    task = task_service.get_task(task_id)
    result = None
    if task is None:
        raise HTTPException(status_code=404, detail="Task not found")
    if task.ready():
        result = task.result
        # If result isinstance of Exception, can we get the traceback?
        if isinstance(result, Exception):
            logger.exception(task.traceback)

        if isinstance(result, dict) and "result" in result:
            result = result["result"]
        elif hasattr(result, "result"):
            result = result.result

    if task.status == "FAILURE":
        result = str(task.result)
        logger.error(f"Task {task_id} failed: {task.traceback}")

    return TaskStatusResponse(status=task.status, result=result)


@router.post(
    "/upload/{flow_id}",
    status_code=HTTPStatus.CREATED,
    deprecated=True,
)
async def create_upload_file(
    file: UploadFile,
    flow_id: UUID,
) -> UploadFileResponse:
    """Upload a file for a specific flow (Deprecated).

    This endpoint is deprecated and will be removed in a future version.
    """
    try:
        flow_id_str = str(flow_id)
        file_path = await asyncio.to_thread(save_uploaded_file, file, folder_name=flow_id_str)

        return UploadFileResponse(
            flow_id=flow_id_str,
            file_path=file_path,
        )
    except Exception as exc:
        logger.exception("Error saving file")
        raise HTTPException(status_code=500, detail=str(exc)) from exc


# get endpoint to return version of langflow
@router.get("/version")
async def get_version():
    return get_version_info()


@router.post("/custom_component", status_code=HTTPStatus.OK)
async def custom_component(
    raw_code: CustomComponentRequest,
    user: CurrentActiveUser,
) -> CustomComponentResponse:
    component = Component(_code=raw_code.code)

    built_frontend_node, component_instance = build_custom_component_template(component, user_id=user.id)
    if raw_code.frontend_node is not None:
        built_frontend_node = component_instance.post_code_processing(built_frontend_node, raw_code.frontend_node)

    type_ = get_instance_name(component_instance)
    return CustomComponentResponse(data=built_frontend_node, type=type_)


@router.post("/custom_component/update", status_code=HTTPStatus.OK)
async def custom_component_update(
    code_request: UpdateCustomComponentRequest,
    user: CurrentActiveUser,
):
    """Update a custom component with the provided code request.

    This endpoint generates the CustomComponentFrontendNode normally but then runs the `update_build_config` method
    on the latest version of the template.
    This ensures that every time it runs, it has the latest version of the template.

    Args:
        code_request (CustomComponentRequest): The code request containing the updated code for the custom component.
        user (User, optional): The user making the request. Defaults to the current active user.

    Returns:
        dict: The updated custom component node.

    """
    try:
        component = Component(_code=code_request.code)
        component_node, cc_instance = build_custom_component_template(
            component,
            user_id=user.id,
        )

        component_node["tool_mode"] = code_request.tool_mode

        if hasattr(cc_instance, "set_attributes"):
            template = code_request.get_template()
            params = {}

            for key, value_dict in template.items():
                if isinstance(value_dict, dict):
                    value = value_dict.get("value")
                    input_type = str(value_dict.get("_input_type"))
                    params[key] = parse_value(value, input_type)

            load_from_db_fields = [
                field_name
                for field_name, field_dict in template.items()
                if isinstance(field_dict, dict) and field_dict.get("load_from_db")
            ]
            params = update_params_with_load_from_db_fields(cc_instance, params, load_from_db_fields)
            cc_instance.set_attributes(params)
        updated_build_config = code_request.get_template()
        cc_instance.update_build_config(
            build_config=updated_build_config,
            field_value=code_request.field_value,
            field_name=code_request.field,
        )
        component_node["template"] = updated_build_config
        if isinstance(cc_instance, Component):
            cc_instance.run_and_validate_update_outputs(
                frontend_node=component_node,
                field_name=code_request.field,
                field_value=code_request.field_value,
            )

    except Exception as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return component_node


@router.get("/config", response_model=ConfigResponse)
async def get_config():
    try:
        from langflow.services.deps import get_settings_service

        settings_service: SettingsService = get_settings_service()

        return {
            "feature_flags": FEATURE_FLAGS,
            **settings_service.settings.model_dump(),
        }
    except Exception as exc:
        raise HTTPException(status_code=500, detail=str(exc)) from exc