import dataclasses import datetime import logging from collections.abc import Mapping, Sequence from enum import StrEnum from typing import Any, ClassVar from sqlalchemy import Engine, orm, select from sqlalchemy.dialects.postgresql import insert from sqlalchemy.orm import Session from sqlalchemy.sql.expression import and_, or_ from core.app.entities.app_invoke_entities import InvokeFrom from core.file.models import File from core.variables import Segment, StringSegment, Variable from core.variables.consts import MIN_SELECTORS_LENGTH from core.variables.segments import ArrayFileSegment, FileSegment from core.variables.types import SegmentType from core.workflow.constants import CONVERSATION_VARIABLE_NODE_ID, ENVIRONMENT_VARIABLE_NODE_ID, SYSTEM_VARIABLE_NODE_ID from core.workflow.enums import SystemVariableKey from core.workflow.nodes import NodeType from core.workflow.nodes.variable_assigner.common.helpers import get_updated_variables from core.workflow.variable_loader import VariableLoader from factories.file_factory import StorageKeyLoader from factories.variable_factory import build_segment, segment_to_variable from models import App, Conversation from models.enums import DraftVariableType from models.workflow import Workflow, WorkflowDraftVariable, WorkflowNodeExecutionModel, is_system_variable_editable _logger = logging.getLogger(__name__) @dataclasses.dataclass(frozen=True) class WorkflowDraftVariableList: variables: list[WorkflowDraftVariable] total: int | None = None class WorkflowDraftVariableError(Exception): pass class VariableResetError(WorkflowDraftVariableError): pass class UpdateNotSupportedError(WorkflowDraftVariableError): pass class DraftVarLoader(VariableLoader): # This implements the VariableLoader interface for loading draft variables. # # ref: core.workflow.variable_loader.VariableLoader # Database engine used for loading variables. _engine: Engine # Application ID for which variables are being loaded. _app_id: str _tenant_id: str _fallback_variables: Sequence[Variable] def __init__( self, engine: Engine, app_id: str, tenant_id: str, fallback_variables: Sequence[Variable] | None = None, ) -> None: self._engine = engine self._app_id = app_id self._tenant_id = tenant_id self._fallback_variables = fallback_variables or [] def _selector_to_tuple(self, selector: Sequence[str]) -> tuple[str, str]: return (selector[0], selector[1]) def load_variables(self, selectors: list[list[str]]) -> list[Variable]: if not selectors: return [] # Map each selector (as a tuple via `_selector_to_tuple`) to its corresponding Variable instance. variable_by_selector: dict[tuple[str, str], Variable] = {} with Session(bind=self._engine, expire_on_commit=False) as session: srv = WorkflowDraftVariableService(session) draft_vars = srv.get_draft_variables_by_selectors(self._app_id, selectors) for draft_var in draft_vars: segment = draft_var.get_value() variable = segment_to_variable( segment=segment, selector=draft_var.get_selector(), id=draft_var.id, name=draft_var.name, description=draft_var.description, ) selector_tuple = self._selector_to_tuple(variable.selector) variable_by_selector[selector_tuple] = variable # Important: files: list[File] = [] for draft_var in draft_vars: value = draft_var.get_value() if isinstance(value, FileSegment): files.append(value.value) elif isinstance(value, ArrayFileSegment): files.extend(value.value) with Session(bind=self._engine) as session: storage_key_loader = StorageKeyLoader(session, tenant_id=self._tenant_id) storage_key_loader.load_storage_keys(files) return list(variable_by_selector.values()) class WorkflowDraftVariableService: _session: Session def __init__(self, session: Session) -> None: self._session = session def get_variable(self, variable_id: str) -> WorkflowDraftVariable | None: return self._session.query(WorkflowDraftVariable).filter(WorkflowDraftVariable.id == variable_id).first() def get_draft_variables_by_selectors( self, app_id: str, selectors: Sequence[list[str]], ) -> list[WorkflowDraftVariable]: ors = [] for selector in selectors: assert len(selector) >= MIN_SELECTORS_LENGTH, f"Invalid selector to get: {selector}" node_id, name = selector[:2] ors.append(and_(WorkflowDraftVariable.node_id == node_id, WorkflowDraftVariable.name == name)) # NOTE(QuantumGhost): Although the number of `or` expressions may be large, as long as # each expression includes conditions on both `node_id` and `name` (which are covered by the unique index), # PostgreSQL can efficiently retrieve the results using a bitmap index scan. # # Alternatively, a `SELECT` statement could be constructed for each selector and # combined using `UNION` to fetch all rows. # Benchmarking indicates that both approaches yield comparable performance. variables = ( self._session.query(WorkflowDraftVariable).where(WorkflowDraftVariable.app_id == app_id, or_(*ors)).all() ) return variables def list_variables_without_values(self, app_id: str, page: int, limit: int) -> WorkflowDraftVariableList: criteria = WorkflowDraftVariable.app_id == app_id total = None query = self._session.query(WorkflowDraftVariable).filter(criteria) if page == 1: total = query.count() variables = ( # Do not load the `value` field. query.options(orm.defer(WorkflowDraftVariable.value)) .order_by(WorkflowDraftVariable.created_at.desc()) .limit(limit) .offset((page - 1) * limit) .all() ) return WorkflowDraftVariableList(variables=variables, total=total) def _list_node_variables(self, app_id: str, node_id: str) -> WorkflowDraftVariableList: criteria = ( WorkflowDraftVariable.app_id == app_id, WorkflowDraftVariable.node_id == node_id, ) query = self._session.query(WorkflowDraftVariable).filter(*criteria) variables = query.order_by(WorkflowDraftVariable.created_at.desc()).all() return WorkflowDraftVariableList(variables=variables) def list_node_variables(self, app_id: str, node_id: str) -> WorkflowDraftVariableList: return self._list_node_variables(app_id, node_id) def list_conversation_variables(self, app_id: str) -> WorkflowDraftVariableList: return self._list_node_variables(app_id, CONVERSATION_VARIABLE_NODE_ID) def list_system_variables(self, app_id: str) -> WorkflowDraftVariableList: return self._list_node_variables(app_id, SYSTEM_VARIABLE_NODE_ID) def get_conversation_variable(self, app_id: str, name: str) -> WorkflowDraftVariable | None: return self._get_variable(app_id=app_id, node_id=CONVERSATION_VARIABLE_NODE_ID, name=name) def get_system_variable(self, app_id: str, name: str) -> WorkflowDraftVariable | None: return self._get_variable(app_id=app_id, node_id=SYSTEM_VARIABLE_NODE_ID, name=name) def get_node_variable(self, app_id: str, node_id: str, name: str) -> WorkflowDraftVariable | None: return self._get_variable(app_id, node_id, name) def _get_variable(self, app_id: str, node_id: str, name: str) -> WorkflowDraftVariable | None: variable = ( self._session.query(WorkflowDraftVariable) .where( WorkflowDraftVariable.app_id == app_id, WorkflowDraftVariable.node_id == node_id, WorkflowDraftVariable.name == name, ) .first() ) return variable def update_variable( self, variable: WorkflowDraftVariable, name: str | None = None, value: Segment | None = None, ) -> WorkflowDraftVariable: if not variable.editable: raise UpdateNotSupportedError(f"variable not support updating, id={variable.id}") if name is not None: variable.set_name(name) if value is not None: variable.set_value(value) variable.last_edited_at = datetime.datetime.now(datetime.UTC).replace(tzinfo=None) self._session.flush() return variable def _reset_conv_var(self, workflow: Workflow, variable: WorkflowDraftVariable) -> WorkflowDraftVariable | None: conv_var_by_name = {i.name: i for i in workflow.conversation_variables} conv_var = conv_var_by_name.get(variable.name) if conv_var is None: self._session.delete(instance=variable) self._session.flush() _logger.warning( "Conversation variable not found for draft variable, id=%s, name=%s", variable.id, variable.name ) return None variable.set_value(conv_var) variable.last_edited_at = None self._session.add(variable) self._session.flush() return variable def _reset_node_var_or_sys_var( self, workflow: Workflow, variable: WorkflowDraftVariable ) -> WorkflowDraftVariable | None: # If a variable does not allow updating, it makes no sence to resetting it. if not variable.editable: return variable # No execution record for this variable, delete the variable instead. if variable.node_execution_id is None: self._session.delete(instance=variable) self._session.flush() _logger.warning("draft variable has no node_execution_id, id=%s, name=%s", variable.id, variable.name) return None query = select(WorkflowNodeExecutionModel).where(WorkflowNodeExecutionModel.id == variable.node_execution_id) node_exec = self._session.scalars(query).first() if node_exec is None: _logger.warning( "Node exectution not found for draft variable, id=%s, name=%s, node_execution_id=%s", variable.id, variable.name, variable.node_execution_id, ) self._session.delete(instance=variable) self._session.flush() return None outputs_dict = node_exec.outputs_dict or {} # a sentinel value used to check the absent of the output variable key. absent = object() if variable.get_variable_type() == DraftVariableType.NODE: # Get node type for proper value extraction node_config = workflow.get_node_config_by_id(variable.node_id) node_type = workflow.get_node_type_from_node_config(node_config) # Note: Based on the implementation in `_build_from_variable_assigner_mapping`, # VariableAssignerNode (both v1 and v2) can only create conversation draft variables. # For consistency, we should simply return when processing VARIABLE_ASSIGNER nodes. # # This implementation must remain synchronized with the `_build_from_variable_assigner_mapping` # and `save` methods. if node_type == NodeType.VARIABLE_ASSIGNER: return variable output_value = outputs_dict.get(variable.name, absent) else: output_value = outputs_dict.get(f"sys.{variable.name}", absent) # We cannot use `is None` to check the existence of an output variable here as # the value of the output may be `None`. if output_value is absent: # If variable not found in execution data, delete the variable self._session.delete(instance=variable) self._session.flush() return None value_seg = WorkflowDraftVariable.build_segment_with_type(variable.value_type, output_value) # Extract variable value using unified logic variable.set_value(value_seg) variable.last_edited_at = None # Reset to indicate this is a reset operation self._session.flush() return variable def reset_variable(self, workflow: Workflow, variable: WorkflowDraftVariable) -> WorkflowDraftVariable | None: variable_type = variable.get_variable_type() if variable_type == DraftVariableType.CONVERSATION: return self._reset_conv_var(workflow, variable) else: return self._reset_node_var_or_sys_var(workflow, variable) def delete_variable(self, variable: WorkflowDraftVariable): self._session.delete(variable) def delete_workflow_variables(self, app_id: str): ( self._session.query(WorkflowDraftVariable) .filter(WorkflowDraftVariable.app_id == app_id) .delete(synchronize_session=False) ) def delete_node_variables(self, app_id: str, node_id: str): return self._delete_node_variables(app_id, node_id) def _delete_node_variables(self, app_id: str, node_id: str): self._session.query(WorkflowDraftVariable).where( WorkflowDraftVariable.app_id == app_id, WorkflowDraftVariable.node_id == node_id, ).delete() def _get_conversation_id_from_draft_variable(self, app_id: str) -> str | None: draft_var = self._get_variable( app_id=app_id, node_id=SYSTEM_VARIABLE_NODE_ID, name=str(SystemVariableKey.CONVERSATION_ID), ) if draft_var is None: return None segment = draft_var.get_value() if not isinstance(segment, StringSegment): _logger.warning( "sys.conversation_id variable is not a string: app_id=%s, id=%s", app_id, draft_var.id, ) return None return segment.value def get_or_create_conversation( self, account_id: str, app: App, workflow: Workflow, ) -> str: """ get_or_create_conversation creates and returns the ID of a conversation for debugging. If a conversation already exists, as determined by the following criteria, its ID is returned: - The system variable `sys.conversation_id` exists in the draft variable table, and - A corresponding conversation record is found in the database. If no such conversation exists, a new conversation is created and its ID is returned. """ conv_id = self._get_conversation_id_from_draft_variable(workflow.app_id) if conv_id is not None: conversation = ( self._session.query(Conversation) .filter( Conversation.id == conv_id, Conversation.app_id == workflow.app_id, ) .first() ) # Only return the conversation ID if it exists and is valid (has a correspond conversation record in DB). if conversation is not None: return conv_id conversation = Conversation( app_id=workflow.app_id, app_model_config_id=app.app_model_config_id, model_provider=None, model_id="", override_model_configs=None, mode=app.mode, name="Draft Debugging Conversation", inputs={}, introduction="", system_instruction="", system_instruction_tokens=0, status="normal", invoke_from=InvokeFrom.DEBUGGER.value, from_source="console", from_end_user_id=None, from_account_id=account_id, ) self._session.add(conversation) self._session.flush() return conversation.id def prefill_conversation_variable_default_values(self, workflow: Workflow): """""" draft_conv_vars: list[WorkflowDraftVariable] = [] for conv_var in workflow.conversation_variables: draft_var = WorkflowDraftVariable.new_conversation_variable( app_id=workflow.app_id, name=conv_var.name, value=conv_var, description=conv_var.description, ) draft_conv_vars.append(draft_var) _batch_upsert_draft_varaible( self._session, draft_conv_vars, policy=_UpsertPolicy.IGNORE, ) class _UpsertPolicy(StrEnum): IGNORE = "ignore" OVERWRITE = "overwrite" def _batch_upsert_draft_varaible( session: Session, draft_vars: Sequence[WorkflowDraftVariable], policy: _UpsertPolicy = _UpsertPolicy.OVERWRITE, ) -> None: if not draft_vars: return None # Although we could use SQLAlchemy ORM operations here, we choose not to for several reasons: # # 1. The variable saving process involves writing multiple rows to the # `workflow_draft_variables` table. Batch insertion significantly improves performance. # 2. Using the ORM would require either: # # a. Checking for the existence of each variable before insertion, # resulting in 2n SQL statements for n variables and potential concurrency issues. # b. Attempting insertion first, then updating if a unique index violation occurs, # which still results in n to 2n SQL statements. # # Both approaches are inefficient and suboptimal. # 3. We do not need to retrieve the results of the SQL execution or populate ORM # model instances with the returned values. # 4. Batch insertion with `ON CONFLICT DO UPDATE` allows us to insert or update all # variables in a single SQL statement, avoiding the issues above. # # For these reasons, we use the SQLAlchemy query builder and rely on dialect-specific # insert operations instead of the ORM layer. stmt = insert(WorkflowDraftVariable).values([_model_to_insertion_dict(v) for v in draft_vars]) if policy == _UpsertPolicy.OVERWRITE: stmt = stmt.on_conflict_do_update( index_elements=WorkflowDraftVariable.unique_app_id_node_id_name(), set_={ # Refresh creation timestamp to ensure updated variables # appear first in chronologically sorted result sets. "created_at": stmt.excluded.created_at, "updated_at": stmt.excluded.updated_at, "last_edited_at": stmt.excluded.last_edited_at, "description": stmt.excluded.description, "value_type": stmt.excluded.value_type, "value": stmt.excluded.value, "visible": stmt.excluded.visible, "editable": stmt.excluded.editable, "node_execution_id": stmt.excluded.node_execution_id, }, ) elif _UpsertPolicy.IGNORE: stmt = stmt.on_conflict_do_nothing(index_elements=WorkflowDraftVariable.unique_app_id_node_id_name()) else: raise Exception("Invalid value for update policy.") session.execute(stmt) def _model_to_insertion_dict(model: WorkflowDraftVariable) -> dict[str, Any]: d: dict[str, Any] = { "app_id": model.app_id, "last_edited_at": None, "node_id": model.node_id, "name": model.name, "selector": model.selector, "value_type": model.value_type, "value": model.value, "node_execution_id": model.node_execution_id, } if model.visible is not None: d["visible"] = model.visible if model.editable is not None: d["editable"] = model.editable if model.created_at is not None: d["created_at"] = model.created_at if model.updated_at is not None: d["updated_at"] = model.updated_at if model.description is not None: d["description"] = model.description return d def _build_segment_for_serialized_values(v: Any) -> Segment: """ Reconstructs Segment objects from serialized values, with special handling for FileSegment and ArrayFileSegment types. This function should only be used when: 1. No explicit type information is available 2. The input value is in serialized form (dict or list) It detects potential file objects in the serialized data and properly rebuilds the appropriate segment type. """ return build_segment(WorkflowDraftVariable.rebuild_file_types(v)) class DraftVariableSaver: # _DUMMY_OUTPUT_IDENTITY is a placeholder output for workflow nodes. # Its sole possible value is `None`. # # This is used to signal the execution of a workflow node when it has no other outputs. _DUMMY_OUTPUT_IDENTITY: ClassVar[str] = "__dummy__" _DUMMY_OUTPUT_VALUE: ClassVar[None] = None # _EXCLUDE_VARIABLE_NAMES_MAPPING maps node types and versions to variable names that # should be excluded when saving draft variables. This prevents certain internal or # technical variables from being exposed in the draft environment, particularly those # that aren't meant to be directly edited or viewed by users. _EXCLUDE_VARIABLE_NAMES_MAPPING: dict[NodeType, frozenset[str]] = { NodeType.LLM: frozenset(["finish_reason"]), NodeType.LOOP: frozenset(["loop_round"]), } # Database session used for persisting draft variables. _session: Session # The application ID associated with the draft variables. # This should match the `Workflow.app_id` of the workflow to which the current node belongs. _app_id: str # The ID of the node for which DraftVariableSaver is saving output variables. _node_id: str # The type of the current node (see NodeType). _node_type: NodeType # _node_execution_id: str # _enclosing_node_id identifies the container node that the current node belongs to. # For example, if the current node is an LLM node inside an Iteration node # or Loop node, then `_enclosing_node_id` refers to the ID of # the containing Iteration or Loop node. # # If the current node is not nested within another node, `_enclosing_node_id` is # `None`. _enclosing_node_id: str | None def __init__( self, session: Session, app_id: str, node_id: str, node_type: NodeType, node_execution_id: str, enclosing_node_id: str | None = None, ): # Important: `node_execution_id` parameter refers to the primary key (`id`) of the # WorkflowNodeExecutionModel/WorkflowNodeExecution, not their `node_execution_id` # field. These are distinct database fields with different purposes. self._session = session self._app_id = app_id self._node_id = node_id self._node_type = node_type self._node_execution_id = node_execution_id self._enclosing_node_id = enclosing_node_id def _create_dummy_output_variable(self): return WorkflowDraftVariable.new_node_variable( app_id=self._app_id, node_id=self._node_id, name=self._DUMMY_OUTPUT_IDENTITY, node_execution_id=self._node_execution_id, value=build_segment(self._DUMMY_OUTPUT_VALUE), visible=False, editable=False, ) def _should_save_output_variables_for_draft(self) -> bool: if self._enclosing_node_id is not None and self._node_type != NodeType.VARIABLE_ASSIGNER: # Currently we do not save output variables for nodes inside loop or iteration. return False return True def _build_from_variable_assigner_mapping(self, process_data: Mapping[str, Any]) -> list[WorkflowDraftVariable]: draft_vars: list[WorkflowDraftVariable] = [] updated_variables = get_updated_variables(process_data) or [] for item in updated_variables: selector = item.selector if len(selector) < MIN_SELECTORS_LENGTH: raise Exception("selector too short") # NOTE(QuantumGhost): only the following two kinds of variable could be updated by # VariableAssigner: ConversationVariable and iteration variable. # We only save conversation variable here. if selector[0] != CONVERSATION_VARIABLE_NODE_ID: continue segment = WorkflowDraftVariable.build_segment_with_type(segment_type=item.value_type, value=item.new_value) draft_vars.append( WorkflowDraftVariable.new_conversation_variable( app_id=self._app_id, name=item.name, value=segment, ) ) # Add a dummy output variable to indicate that this node is executed. draft_vars.append(self._create_dummy_output_variable()) return draft_vars def _build_variables_from_start_mapping(self, output: Mapping[str, Any]) -> list[WorkflowDraftVariable]: draft_vars = [] has_non_sys_variables = False for name, value in output.items(): value_seg = _build_segment_for_serialized_values(value) node_id, name = self._normalize_variable_for_start_node(name) # If node_id is not `sys`, it means that the variable is a user-defined input field # in `Start` node. if node_id != SYSTEM_VARIABLE_NODE_ID: draft_vars.append( WorkflowDraftVariable.new_node_variable( app_id=self._app_id, node_id=self._node_id, name=name, node_execution_id=self._node_execution_id, value=value_seg, visible=True, editable=True, ) ) has_non_sys_variables = True else: if name == SystemVariableKey.FILES: # Here we know the type of variable must be `array[file]`, we # just build files from the value. files = [File.model_validate(v) for v in value] if files: value_seg = WorkflowDraftVariable.build_segment_with_type(SegmentType.ARRAY_FILE, files) else: value_seg = ArrayFileSegment(value=[]) draft_vars.append( WorkflowDraftVariable.new_sys_variable( app_id=self._app_id, name=name, node_execution_id=self._node_execution_id, value=value_seg, editable=self._should_variable_be_editable(node_id, name), ) ) if not has_non_sys_variables: draft_vars.append(self._create_dummy_output_variable()) return draft_vars def _normalize_variable_for_start_node(self, name: str) -> tuple[str, str]: if not name.startswith(f"{SYSTEM_VARIABLE_NODE_ID}."): return self._node_id, name _, name_ = name.split(".", maxsplit=1) return SYSTEM_VARIABLE_NODE_ID, name_ def _build_variables_from_mapping(self, output: Mapping[str, Any]) -> list[WorkflowDraftVariable]: draft_vars = [] for name, value in output.items(): if not self._should_variable_be_saved(name): _logger.debug( "Skip saving variable as it has been excluded by its node_type, name=%s, node_type=%s", name, self._node_type, ) continue if isinstance(value, Segment): value_seg = value else: value_seg = _build_segment_for_serialized_values(value) draft_vars.append( WorkflowDraftVariable.new_node_variable( app_id=self._app_id, node_id=self._node_id, name=name, node_execution_id=self._node_execution_id, value=value_seg, visible=self._should_variable_be_visible(self._node_id, self._node_type, name), ) ) return draft_vars def save( self, process_data: Mapping[str, Any] | None = None, outputs: Mapping[str, Any] | None = None, ): draft_vars: list[WorkflowDraftVariable] = [] if outputs is None: outputs = {} if process_data is None: process_data = {} if not self._should_save_output_variables_for_draft(): return if self._node_type == NodeType.VARIABLE_ASSIGNER: draft_vars = self._build_from_variable_assigner_mapping(process_data=process_data) elif self._node_type == NodeType.START: draft_vars = self._build_variables_from_start_mapping(outputs) else: draft_vars = self._build_variables_from_mapping(outputs) _batch_upsert_draft_varaible(self._session, draft_vars) @staticmethod def _should_variable_be_editable(node_id: str, name: str) -> bool: if node_id in (CONVERSATION_VARIABLE_NODE_ID, ENVIRONMENT_VARIABLE_NODE_ID): return False if node_id == SYSTEM_VARIABLE_NODE_ID and not is_system_variable_editable(name): return False return True @staticmethod def _should_variable_be_visible(node_id: str, node_type: NodeType, name: str) -> bool: if node_type in NodeType.IF_ELSE: return False if node_id == SYSTEM_VARIABLE_NODE_ID and not is_system_variable_editable(name): return False return True def _should_variable_be_saved(self, name: str) -> bool: exclude_var_names = self._EXCLUDE_VARIABLE_NAMES_MAPPING.get(self._node_type) if exclude_var_names is None: return True return name not in exclude_var_names