refactor: move workflow package to dify_graph (#32844)

api/dify_graph/graph_events/node.py

@@ -0,0 +1,97 @@
+from collections.abc import Sequence
+from datetime import datetime
+
+from pydantic import Field
+
+from core.rag.entities.citation_metadata import RetrievalSourceMetadata
+from dify_graph.entities import AgentNodeStrategyInit
+from dify_graph.entities.pause_reason import PauseReason
+
+from .base import GraphNodeEventBase
+
+
+class NodeRunStartedEvent(GraphNodeEventBase):
+    node_title: str
+    predecessor_node_id: str | None = None
+    agent_strategy: AgentNodeStrategyInit | None = None
+    start_at: datetime = Field(..., description="node start time")
+
+    # FIXME(-LAN-): only for ToolNode
+    provider_type: str = ""
+    provider_id: str = ""
+
+
+class NodeRunStreamChunkEvent(GraphNodeEventBase):
+    # Spec-compliant fields
+    selector: Sequence[str] = Field(
+        ..., description="selector identifying the output location (e.g., ['nodeA', 'text'])"
+    )
+    chunk: str = Field(..., description="the actual chunk content")
+    is_final: bool = Field(default=False, description="indicates if this is the last chunk")
+
+
+class NodeRunRetrieverResourceEvent(GraphNodeEventBase):
+    retriever_resources: Sequence[RetrievalSourceMetadata] = Field(..., description="retriever resources")
+    context: str = Field(..., description="context")
+
+
+class NodeRunSucceededEvent(GraphNodeEventBase):
+    start_at: datetime = Field(..., description="node start time")
+
+
+class NodeRunFailedEvent(GraphNodeEventBase):
+    error: str = Field(..., description="error")
+    start_at: datetime = Field(..., description="node start time")
+
+
+class NodeRunExceptionEvent(GraphNodeEventBase):
+    error: str = Field(..., description="error")
+    start_at: datetime = Field(..., description="node start time")
+
+
+class NodeRunRetryEvent(NodeRunStartedEvent):
+    error: str = Field(..., description="error")
+    retry_index: int = Field(..., description="which retry attempt is about to be performed")
+
+
+class NodeRunHumanInputFormFilledEvent(GraphNodeEventBase):
+    """Emitted when a HumanInput form is submitted and before the node finishes."""
+
+    node_title: str = Field(..., description="HumanInput node title")
+    rendered_content: str = Field(..., description="Markdown content rendered with user inputs.")
+    action_id: str = Field(..., description="User action identifier chosen in the form.")
+    action_text: str = Field(..., description="Display text of the chosen action button.")
+
+
+class NodeRunHumanInputFormTimeoutEvent(GraphNodeEventBase):
+    """Emitted when a HumanInput form times out."""
+
+    node_title: str = Field(..., description="HumanInput node title")
+    expiration_time: datetime = Field(..., description="Form expiration time")
+
+
+class NodeRunPauseRequestedEvent(GraphNodeEventBase):
+    reason: PauseReason = Field(..., description="pause reason")
+
+
+def is_node_result_event(event: GraphNodeEventBase) -> bool:
+    """
+    Check if an event is a final result event from node execution.
+
+    A result event indicates the completion of a node execution and contains
+    runtime information such as inputs, outputs, or error details.
+
+    Args:
+        event: The event to check
+
+    Returns:
+        True if the event is a node result event (succeeded/failed/paused), False otherwise
+    """
+    return isinstance(
+        event,
+        (
+            NodeRunSucceededEvent,
+            NodeRunFailedEvent,
+            NodeRunPauseRequestedEvent,
+        ),
+    )