Read the current implementation and consider the following problem (vibe-kanban 25d8b973)

Currently, the HumanInput node yields a `HumanInputFormFilledEvent` event while form is submmited. However, for form level timeout, current no event about timeout is emitted. This makes the frontend UI not updated while the events of time out are sent to the frontend.

Analysis this problem, propose a way to resolve this issue.

api/core/app/apps/advanced_chat/generate_task_pipeline.py

@@ -25,6 +25,7 @@ from core.app.entities.queue_entities import (
     QueueAnnotationReplyEvent,
     QueueErrorEvent,
     QueueHumanInputFormFilledEvent,
+    QueueHumanInputFormTimeoutEvent,
     QueueIterationCompletedEvent,
     QueueIterationNextEvent,
     QueueIterationStartEvent,
@@ -692,6 +693,14 @@ class AdvancedChatAppGenerateTaskPipeline(GraphRuntimeStateSupport):
             event=event, task_id=self._application_generate_entity.task_id
         )
 
+    def _handle_human_input_form_timeout_event(
+        self, event: QueueHumanInputFormTimeoutEvent, **kwargs
+    ) -> Generator[StreamResponse, None, None]:
+        """Handle human input form timeout events."""
+        yield self._workflow_response_converter.human_input_form_timeout_to_stream_response(
+            event=event, task_id=self._application_generate_entity.task_id
+        )
+
     def _persist_human_input_extra_content(self, *, node_id: str | None = None, form_id: str | None = None) -> None:
         if not self._workflow_run_id or not self._message_id:
             return
@@ -774,6 +783,7 @@ class AdvancedChatAppGenerateTaskPipeline(GraphRuntimeStateSupport):
             QueueAdvancedChatMessageEndEvent: self._handle_advanced_chat_message_end_event,
             QueueAgentLogEvent: self._handle_agent_log_event,
             QueueHumanInputFormFilledEvent: self._handle_human_input_form_filled_event,
+            QueueHumanInputFormTimeoutEvent: self._handle_human_input_form_timeout_event,
         }
 
     def _dispatch_event(

api/core/app/apps/common/workflow_response_converter.py

@@ -9,6 +9,7 @@ from core.app.entities.app_invoke_entities import AdvancedChatAppGenerateEntity,
 from core.app.entities.queue_entities import (
     QueueAgentLogEvent,
     QueueHumanInputFormFilledEvent,
+    QueueHumanInputFormTimeoutEvent,
     QueueIterationCompletedEvent,
     QueueIterationNextEvent,
     QueueIterationStartEvent,
@@ -25,6 +26,7 @@ from core.app.entities.queue_entities import (
 from core.app.entities.task_entities import (
     AgentLogStreamResponse,
     HumanInputFormFilledResponse,
+    HumanInputFormTimeoutResponse,
     HumanInputRequiredResponse,
     IterationNodeCompletedStreamResponse,
     IterationNodeNextStreamResponse,
@@ -338,6 +340,20 @@ class WorkflowResponseConverter:
             ),
         )
 
+    def human_input_form_timeout_to_stream_response(
+        self, *, event: QueueHumanInputFormTimeoutEvent, task_id: str
+    ) -> HumanInputFormTimeoutResponse:
+        run_id = self._ensure_workflow_run_id()
+        return HumanInputFormTimeoutResponse(
+            task_id=task_id,
+            workflow_run_id=run_id,
+            data=HumanInputFormTimeoutResponse.Data(
+                node_id=event.node_id,
+                node_title=event.node_title,
+                expiration_time=int(event.expiration_time.timestamp()),
+            ),
+        )
+
     @classmethod
     def workflow_run_result_to_finish_response(
         cls,

api/core/app/apps/workflow/generate_task_pipeline.py

@@ -18,6 +18,7 @@ from core.app.entities.queue_entities import (
     QueueAgentLogEvent,
     QueueErrorEvent,
     QueueHumanInputFormFilledEvent,
+    QueueHumanInputFormTimeoutEvent,
     QueueIterationCompletedEvent,
     QueueIterationNextEvent,
     QueueIterationStartEvent,
@@ -523,6 +524,14 @@ class WorkflowAppGenerateTaskPipeline(GraphRuntimeStateSupport):
             event=event, task_id=self._application_generate_entity.task_id
         )
 
+    def _handle_human_input_form_timeout_event(
+        self, event: QueueHumanInputFormTimeoutEvent, **kwargs
+    ) -> Generator[StreamResponse, None, None]:
+        """Handle human input form timeout events."""
+        yield self._workflow_response_converter.human_input_form_timeout_to_stream_response(
+            event=event, task_id=self._application_generate_entity.task_id
+        )
+
     def _get_event_handlers(self) -> dict[type, Callable]:
         """Get mapping of event types to their handlers using fluent pattern."""
         return {
@@ -550,6 +559,7 @@ class WorkflowAppGenerateTaskPipeline(GraphRuntimeStateSupport):
             # Agent events
             QueueAgentLogEvent: self._handle_agent_log_event,
             QueueHumanInputFormFilledEvent: self._handle_human_input_form_filled_event,
+            QueueHumanInputFormTimeoutEvent: self._handle_human_input_form_timeout_event,
         }
 
     def _dispatch_event(

api/core/app/apps/workflow_app_runner.py

@@ -8,6 +8,7 @@ from core.app.entities.queue_entities import (
     AppQueueEvent,
     QueueAgentLogEvent,
     QueueHumanInputFormFilledEvent,
+    QueueHumanInputFormTimeoutEvent,
     QueueIterationCompletedEvent,
     QueueIterationNextEvent,
     QueueIterationStartEvent,
@@ -42,6 +43,7 @@ from core.workflow.graph_events import (
     NodeRunExceptionEvent,
     NodeRunFailedEvent,
     NodeRunHumanInputFormFilledEvent,
+    NodeRunHumanInputFormTimeoutEvent,
     NodeRunIterationFailedEvent,
     NodeRunIterationNextEvent,
     NodeRunIterationStartedEvent,
@@ -393,6 +395,15 @@ class WorkflowBasedAppRunner:
                     action_text=event.action_text,
                 )
             )
+        elif isinstance(event, NodeRunHumanInputFormTimeoutEvent):
+            self._publish_event(
+                QueueHumanInputFormTimeoutEvent(
+                    node_id=event.node_id,
+                    node_type=event.node_type,
+                    node_title=event.node_title,
+                    expiration_time=event.expiration_time,
+                )
+            )
         elif isinstance(event, NodeRunRetryEvent):
             node_run_result = event.node_run_result
             inputs = node_run_result.inputs

api/core/app/entities/queue_entities.py

@@ -50,6 +50,7 @@ class QueueEvent(StrEnum):
     RETRY = "retry"
     PAUSE = "pause"
     HUMAN_INPUT_FORM_FILLED = "human_input_form_filled"
+    HUMAN_INPUT_FORM_TIMEOUT = "human_input_form_timeout"
 
 
 class AppQueueEvent(BaseModel):
@@ -506,6 +507,19 @@ class QueueHumanInputFormFilledEvent(AppQueueEvent):
     action_text: str
 
 
+class QueueHumanInputFormTimeoutEvent(AppQueueEvent):
+    """
+    QueueHumanInputFormTimeoutEvent entity
+    """
+
+    event: QueueEvent = QueueEvent.HUMAN_INPUT_FORM_TIMEOUT
+
+    node_id: str
+    node_type: NodeType
+    node_title: str
+    expiration_time: datetime
+
+
 class QueueMessage(BaseModel):
     """
     QueueMessage abstract entity

api/core/app/entities/task_entities.py

@@ -87,6 +87,7 @@ class StreamEvent(StrEnum):
     AGENT_LOG = "agent_log"
     HUMAN_INPUT_REQUIRED = "human_input_required"
     HUMAN_INPUT_FORM_FILLED = "human_input_form_filled"
+    HUMAN_INPUT_FORM_TIMEOUT = "human_input_form_timeout"
 
 
 class StreamResponse(BaseModel):
@@ -305,6 +306,21 @@ class HumanInputFormFilledResponse(StreamResponse):
     data: Data
 
 
+class HumanInputFormTimeoutResponse(StreamResponse):
+    class Data(BaseModel):
+        """
+        Data entity
+        """
+
+        node_id: str
+        node_title: str
+        expiration_time: int
+
+    event: StreamEvent = StreamEvent.HUMAN_INPUT_FORM_TIMEOUT
+    workflow_run_id: str
+    data: Data
+
+
 class NodeStartStreamResponse(StreamResponse):
     """
     NodeStartStreamResponse entity

api/core/workflow/graph_events/__init__.py

@@ -39,6 +39,7 @@ from .node import (
     NodeRunExceptionEvent,
     NodeRunFailedEvent,
     NodeRunHumanInputFormFilledEvent,
+    NodeRunHumanInputFormTimeoutEvent,
     NodeRunPauseRequestedEvent,
     NodeRunRetrieverResourceEvent,
     NodeRunRetryEvent,
@@ -61,6 +62,7 @@ __all__ = [
     "NodeRunExceptionEvent",
     "NodeRunFailedEvent",
     "NodeRunHumanInputFormFilledEvent",
+    "NodeRunHumanInputFormTimeoutEvent",
     "NodeRunIterationFailedEvent",
     "NodeRunIterationNextEvent",
     "NodeRunIterationStartedEvent",

api/core/workflow/graph_events/node.py

@@ -63,5 +63,12 @@ class NodeRunHumanInputFormFilledEvent(GraphNodeEventBase):
     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")

api/core/workflow/node_events/__init__.py

@@ -14,6 +14,7 @@ from .loop import (
 )
 from .node import (
     HumanInputFormFilledEvent,
+    HumanInputFormTimeoutEvent,
     ModelInvokeCompletedEvent,
     PauseRequestedEvent,
     RunRetrieverResourceEvent,
@@ -25,6 +26,7 @@ from .node import (
 __all__ = [
     "AgentLogEvent",
     "HumanInputFormFilledEvent",
+    "HumanInputFormTimeoutEvent",
     "IterationFailedEvent",
     "IterationNextEvent",
     "IterationStartedEvent",

api/core/workflow/node_events/node.py

@@ -56,3 +56,10 @@ class HumanInputFormFilledEvent(NodeEventBase):
     rendered_content: str
     action_id: str
     action_text: str
+
+
+class HumanInputFormTimeoutEvent(NodeEventBase):
+    """Event emitted when a human input form times out."""
+
+    node_title: str
+    expiration_time: datetime

api/core/workflow/nodes/base/node.py

@@ -17,6 +17,7 @@ from core.workflow.graph_events import (
     NodeRunAgentLogEvent,
     NodeRunFailedEvent,
     NodeRunHumanInputFormFilledEvent,
+    NodeRunHumanInputFormTimeoutEvent,
     NodeRunIterationFailedEvent,
     NodeRunIterationNextEvent,
     NodeRunIterationStartedEvent,
@@ -34,6 +35,7 @@ from core.workflow.graph_events import (
 from core.workflow.node_events import (
     AgentLogEvent,
     HumanInputFormFilledEvent,
+    HumanInputFormTimeoutEvent,
     IterationFailedEvent,
     IterationNextEvent,
     IterationStartedEvent,
@@ -649,6 +651,16 @@ class Node(Generic[NodeDataT]):
             action_text=event.action_text,
         )
 
+    @_dispatch.register
+    def _(self, event: HumanInputFormTimeoutEvent):
+        return NodeRunHumanInputFormTimeoutEvent(
+            id=self.execution_id,
+            node_id=self._node_id,
+            node_type=self.node_type,
+            node_title=event.node_title,
+            expiration_time=event.expiration_time,
+        )
+
     @_dispatch.register
     def _(self, event: LoopStartedEvent) -> NodeRunLoopStartedEvent:
         return NodeRunLoopStartedEvent(

api/core/workflow/nodes/human_input/human_input_node.py

@@ -7,7 +7,12 @@ from core.app.entities.app_invoke_entities import InvokeFrom
 from core.repositories.human_input_reposotiry import HumanInputFormRepositoryImpl
 from core.workflow.entities.pause_reason import HumanInputRequired
 from core.workflow.enums import NodeExecutionType, NodeType, WorkflowNodeExecutionStatus
-from core.workflow.node_events import HumanInputFormFilledEvent, NodeRunResult, PauseRequestedEvent
+from core.workflow.node_events import (
+    HumanInputFormFilledEvent,
+    HumanInputFormTimeoutEvent,
+    NodeRunResult,
+    PauseRequestedEvent,
+)
 from core.workflow.node_events.base import NodeEventBase
 from core.workflow.node_events.node import StreamCompletedEvent
 from core.workflow.nodes.base.node import Node
@@ -245,6 +250,10 @@ class HumanInputNode(Node[HumanInputNodeData]):
             return
 
         if form.status == HumanInputFormStatus.TIMEOUT or form.expiration_time <= naive_utc_now():
+            yield HumanInputFormTimeoutEvent(
+                node_title=self._node_data.title,
+                expiration_time=form.expiration_time,
+            )
             yield StreamCompletedEvent(
                 node_run_result=NodeRunResult(
                     status=WorkflowNodeExecutionStatus.SUCCEEDED,

api/tests/unit_tests/core/app/apps/common/test_workflow_response_converter_human_input.py

@@ -1,8 +1,9 @@
+from datetime import UTC, datetime
 from types import SimpleNamespace
 
 from core.app.apps.common.workflow_response_converter import WorkflowResponseConverter
 from core.app.entities.app_invoke_entities import InvokeFrom
-from core.app.entities.queue_entities import QueueHumanInputFormFilledEvent
+from core.app.entities.queue_entities import QueueHumanInputFormFilledEvent, QueueHumanInputFormTimeoutEvent
 from core.workflow.entities.workflow_start_reason import WorkflowStartReason
 from core.workflow.runtime import GraphRuntimeState, VariablePool
 from core.workflow.system_variable import SystemVariable
@@ -60,3 +61,27 @@ def test_human_input_form_filled_stream_response_contains_rendered_content():
     assert resp.data.node_title == "Human Input"
     assert resp.data.rendered_content.startswith("# Title")
     assert resp.data.action_id == "Approve"
+
+
+def test_human_input_form_timeout_stream_response_contains_timeout_metadata():
+    converter = _build_converter()
+    converter.workflow_start_to_stream_response(
+        task_id="task-1",
+        workflow_run_id="run-1",
+        workflow_id="wf-1",
+        reason=WorkflowStartReason.INITIAL,
+    )
+
+    queue_event = QueueHumanInputFormTimeoutEvent(
+        node_id="node-1",
+        node_type="human-input",
+        node_title="Human Input",
+        expiration_time=datetime(2025, 1, 1, tzinfo=UTC),
+    )
+
+    resp = converter.human_input_form_timeout_to_stream_response(event=queue_event, task_id="task-1")
+
+    assert resp.workflow_run_id == "run-1"
+    assert resp.data.node_id == "node-1"
+    assert resp.data.node_title == "Human Input"
+    assert resp.data.expiration_time == 1735689600

api/tests/unit_tests/core/workflow/nodes/human_input/test_entities.py

@@ -80,9 +80,7 @@ class TestFormInput:
         """Test text input with constant default value."""
         default = FormInputDefault(type=PlaceholderType.CONSTANT, value="Enter your response here...")
 
-        form_input = FormInput(
+        form_input = FormInput(type=FormInputType.TEXT_INPUT, output_variable_name="user_input", default=default)
-            type=FormInputType.TEXT_INPUT, output_variable_name="user_input", default=default
-        )
 
         assert form_input.type == FormInputType.TEXT_INPUT
         assert form_input.output_variable_name == "user_input"
@@ -93,9 +91,7 @@ class TestFormInput:
         """Test text input with variable default value."""
         default = FormInputDefault(type=PlaceholderType.VARIABLE, selector=["node_123", "output_var"])
 
-        form_input = FormInput(
+        form_input = FormInput(type=FormInputType.TEXT_INPUT, output_variable_name="user_input", default=default)
-            type=FormInputType.TEXT_INPUT, output_variable_name="user_input", default=default
-        )
 
         assert form_input.default.type == PlaceholderType.VARIABLE
         assert form_input.default.selector == ["node_123", "output_var"]

api/tests/unit_tests/core/workflow/nodes/human_input/test_human_input_form_filled_event.py

@@ -7,6 +7,7 @@ from core.workflow.entities.graph_init_params import GraphInitParams
 from core.workflow.enums import NodeType
 from core.workflow.graph_events import (
     NodeRunHumanInputFormFilledEvent,
+    NodeRunHumanInputFormTimeoutEvent,
     NodeRunStartedEvent,
 )
 from core.workflow.nodes.human_input.enums import HumanInputFormStatus
@@ -86,6 +87,67 @@ def _build_node(form_content: str = "Please enter your name:\n\n{{#$output.name#
     )
 
 
+def _build_timeout_node() -> HumanInputNode:
+    system_variables = SystemVariable.empty()
+    system_variables.workflow_execution_id = str(uuid.uuid4())
+    graph_runtime_state = GraphRuntimeState(
+        variable_pool=VariablePool(system_variables=system_variables, user_inputs={}, environment_variables=[]),
+        start_at=0.0,
+    )
+    graph_init_params = GraphInitParams(
+        tenant_id="tenant",
+        app_id="app",
+        workflow_id="workflow",
+        graph_config={"nodes": [], "edges": []},
+        user_id="user",
+        user_from=UserFrom.ACCOUNT,
+        invoke_from=InvokeFrom.SERVICE_API,
+        call_depth=0,
+    )
+
+    config = {
+        "id": "node-1",
+        "type": NodeType.HUMAN_INPUT.value,
+        "data": {
+            "title": "Human Input",
+            "form_content": "Please enter your name:\n\n{{#$output.name#}}",
+            "inputs": [
+                {
+                    "type": "text_input",
+                    "output_variable_name": "name",
+                    "default": {"type": "constant", "value": ""},
+                }
+            ],
+            "user_actions": [
+                {
+                    "id": "Accept",
+                    "title": "Approve",
+                    "button_style": "default",
+                }
+            ],
+        },
+    }
+
+    fake_form = SimpleNamespace(
+        id="form-1",
+        rendered_content="content",
+        submitted=False,
+        selected_action_id=None,
+        submitted_data=None,
+        status=HumanInputFormStatus.TIMEOUT,
+        expiration_time=naive_utc_now() - datetime.timedelta(minutes=1),
+    )
+
+    repo = _FakeFormRepository(fake_form)
+    return HumanInputNode(
+        id="node-1",
+        config=config,
+        graph_init_params=graph_init_params,
+        graph_runtime_state=graph_runtime_state,
+        form_repository=repo,
+    )
+
+
 def test_human_input_node_emits_form_filled_event_before_succeeded():
     node = _build_node()
 
@@ -99,3 +161,15 @@ def test_human_input_node_emits_form_filled_event_before_succeeded():
     assert filled_event.rendered_content.endswith("Alice")
     assert filled_event.action_id == "Accept"
     assert filled_event.action_text == "Approve"
+
+
+def test_human_input_node_emits_timeout_event_before_succeeded():
+    node = _build_timeout_node()
+
+    events = list(node.run())
+
+    assert isinstance(events[0], NodeRunStartedEvent)
+    assert isinstance(events[1], NodeRunHumanInputFormTimeoutEvent)
+
+    timeout_event = events[1]
+    assert timeout_event.node_title == "Human Input"

api/tests/unit_tests/libs/_human_input/test_form_service.py

@@ -304,9 +304,7 @@ class TestFormValidation:
             "tenant_id": "tenant-abc",
             "app_id": "app-def",
             "form_content": "Test form",
-            "inputs": [
+            "inputs": [FormInput(type=FormInputType.TEXT_INPUT, output_variable_name="required_input", default=None)],
-                FormInput(type=FormInputType.TEXT_INPUT, output_variable_name="required_input", default=None)
-            ],
             "user_actions": [UserAction(id="submit", title="Submit")],
             "timeout": 1,
             "timeout_unit": TimeoutUnit.HOUR,