refactor(api): update /config endpoint to use ConfigResponse.from_settings (#8674)

* refactor: update config response handling and import structure

- Moved EventManager import to the correct module path.
- Refactored get_config endpoint to utilize ConfigResponse.from_settings for improved clarity and maintainability.
- Updated ConfigResponse to include a class method for instantiating from Settings, enhancing the encapsulation of configuration logic.

* 📝 Add docstrings to `improve-docs-and-configsetup` (#8677)

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

* [autofix.ci] apply automated fixes

* [autofix.ci] apply automated fixes

---------

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

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

@@ -49,13 +49,12 @@ from langflow.services.database.models.flow.model import Flow, 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_telemetry_service
-from langflow.services.settings.feature_flags import FEATURE_FLAGS
 from langflow.services.telemetry.schema import RunPayload
 from langflow.utils.compression import compress_response
 from langflow.utils.version import get_version_info
 
 if TYPE_CHECKING:
-    from langflow.services.event_manager import EventManager
+    from langflow.events.event_manager import EventManager
     from langflow.services.settings.service import SettingsService
 
 router = APIRouter(tags=["Base"])
@@ -681,22 +680,13 @@ async def custom_component_update(
     code_request: UpdateCustomComponentRequest,
     user: CurrentActiveUser,
 ):
-    """Update a custom component with the provided code request.
+    """Update an existing custom component with new code and configuration.
 
-    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.
+    Processes the provided code and template updates, applies parameter changes (including those loaded from the database), updates the component's build configuration, and validates outputs. Returns the updated component node as a JSON-serializable dictionary.
 
     Raises:
-        HTTPException: If there's an error building or updating the component
-        SerializationError: If there's an error serializing the component to JSON
+        HTTPException: If an error occurs during component building or updating.
+        SerializationError: If serialization of the updated component node fails.
     """
     try:
         component = Component(_code=code_request.code)
@@ -752,14 +742,19 @@ async def custom_component_update(
         raise SerializationError.from_exception(exc, data=component_node) from exc
 
 
-@router.get("/config", response_model=ConfigResponse)
-async def get_config():
+@router.get("/config")
+async def get_config() -> ConfigResponse:
+    """Retrieve the current application configuration settings.
+
+    Returns:
+        ConfigResponse: The configuration settings of the application.
+
+    Raises:
+        HTTPException: If an error occurs while retrieving the configuration.
+    """
     try:
         settings_service: SettingsService = get_settings_service()
+        return ConfigResponse.from_settings(settings_service.settings)
 
-        return {
-            "feature_flags": FEATURE_FLAGS,
-            **settings_service.settings.model_dump(),
-        }
     except Exception as exc:
         raise HTTPException(status_code=500, detail=str(exc)) from exc

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

@@ -17,13 +17,13 @@ from langflow.graph.schema import RunOutputs
 from langflow.schema.dotdict import dotdict
 from langflow.schema.graph import Tweaks
 from langflow.schema.schema import InputType, OutputType, OutputValue
-from langflow.serialization import constants as serialization_constants
 from langflow.serialization.serialization import get_max_items_length, get_max_text_length, serialize
 from langflow.services.database.models.api_key.model import ApiKeyRead
 from langflow.services.database.models.base import orjson_dumps
 from langflow.services.database.models.flow.model import FlowCreate, FlowRead
 from langflow.services.database.models.user.model import UserRead
-from langflow.services.settings.feature_flags import FeatureFlags
+from langflow.services.settings.base import Settings
+from langflow.services.settings.feature_flags import FEATURE_FLAGS, FeatureFlags
 from langflow.services.tracing.schema import Log
 
 
@@ -395,8 +395,8 @@ class FlowDataRequest(BaseModel):
 
 class ConfigResponse(BaseModel):
     feature_flags: FeatureFlags
-    serialization_max_items_length: int = serialization_constants.MAX_ITEMS_LENGTH
-    serialization_max_text_length: int = serialization_constants.MAX_TEXT_LENGTH
+    serialization_max_items_length: int
+    serialization_max_text_length: int
     frontend_timeout: int
     auto_saving: bool
     auto_saving_interval: int
@@ -407,6 +407,31 @@ class ConfigResponse(BaseModel):
     public_flow_expiration: int
     event_delivery: Literal["polling", "streaming", "direct"]
 
+    @classmethod
+    def from_settings(cls, settings: Settings) -> "ConfigResponse":
+        """Create a ConfigResponse instance using values from a Settings object and global feature flags.
+
+        Parameters:
+            settings (Settings): The Settings object containing configuration values.
+
+        Returns:
+            ConfigResponse: An instance populated with configuration and feature flag values.
+        """
+        return cls(
+            feature_flags=FEATURE_FLAGS,
+            serialization_max_items_length=settings.max_items_length,
+            serialization_max_text_length=settings.max_text_length,
+            frontend_timeout=settings.frontend_timeout,
+            auto_saving=settings.auto_saving,
+            auto_saving_interval=settings.auto_saving_interval,
+            health_check_max_retries=settings.health_check_max_retries,
+            max_file_size_upload=settings.max_file_size_upload,
+            webhook_polling_interval=settings.webhook_polling_interval,
+            public_flow_cleanup_interval=settings.public_flow_cleanup_interval,
+            public_flow_expiration=settings.public_flow_expiration,
+            event_delivery=settings.event_delivery,
+        )
+
 
 class CancelFlowResponse(BaseModel):
     """Response model for flow build cancellation."""