fix(api): fix variable type handling in `Start` node.

Fix the issue that `file` and `array[file]` variable in `Start` node are recognized as `object`
type.

api/controllers/console/app/workflow.py

@@ -439,6 +439,7 @@ class DraftWorkflowNodeRunApi(Resource):
             raise ValueError("Workflow not initialized")
         files = _parse_file(draft_workflow, args.get("files"))
         workflow_service = WorkflowService()
+
         workflow_node_execution = workflow_service.run_draft_workflow_node(
             app_model=app_model,
             draft_workflow=draft_workflow,

api/core/app/app_config/entities.py

@@ -104,6 +104,7 @@ class VariableEntity(BaseModel):
     Variable Entity.
     """
 
+    # `variable` records the name of the variable in user inputs.
     variable: str
     label: str
     description: str = ""

api/core/workflow/workflow_entry.py

@@ -120,7 +120,7 @@ class WorkflowEntry:
         workflow: Workflow,
         node_id: str,
         user_id: str,
-        user_inputs: dict,
+        user_inputs: Mapping[str, Any],
         variable_pool: VariablePool,
         variable_loader: VariableLoader = DUMMY_VARIABLE_LOADER,
     ) -> tuple[BaseNode, Generator[NodeEvent | InNodeEvent, None, None]]:
@@ -326,7 +326,7 @@ class WorkflowEntry:
         cls,
         *,
         variable_mapping: Mapping[str, Sequence[str]],
-        user_inputs: dict,
+        user_inputs: Mapping[str, Any],
         variable_pool: VariablePool,
         tenant_id: str,
     ) -> None:

api/services/workflow_service.py

@@ -9,6 +9,7 @@ from uuid import uuid4
 from sqlalchemy import select
 from sqlalchemy.orm import Session
 
+from core.app.app_config.entities import VariableEntityType
 from core.app.apps.advanced_chat.app_config_manager import AdvancedChatAppConfigManager
 from core.app.apps.workflow.app_config_manager import WorkflowAppConfigManager
 from core.app.entities.app_invoke_entities import InvokeFrom
@@ -27,9 +28,11 @@ from core.workflow.nodes.enums import ErrorStrategy
 from core.workflow.nodes.event import RunCompletedEvent
 from core.workflow.nodes.event.types import NodeEvent
 from core.workflow.nodes.node_mapping import LATEST_VERSION, NODE_TYPE_CLASSES_MAPPING
+from core.workflow.nodes.start.entities import StartNodeData
 from core.workflow.workflow_entry import WorkflowEntry
 from events.app_event import app_draft_workflow_was_synced, app_published_workflow_was_updated
 from extensions.ext_database import db
+from factories.file_factory import build_from_mapping, build_from_mappings
 from models.account import Account
 from models.model import App, AppMode
 from models.tools import WorkflowToolProvider
@@ -311,7 +314,7 @@ class WorkflowService:
         app_model: App,
         draft_workflow: Workflow,
         node_id: str,
-        user_inputs: dict,
+        user_inputs: Mapping[str, Any],
         account: Account,
         query: str = "",
         files: Sequence[File] | None = None,
@@ -326,7 +329,8 @@ class WorkflowService:
             draft_var_srv.prefill_conversation_variable_default_values(draft_workflow)
 
         node_config = draft_workflow.get_node_config_by_id(node_id)
-        node_type = NodeType(node_config.get("data", {}).get("type"))
+        node_type = Workflow.get_node_type_from_node_config(node_config)
+        node_data = node_config.get("data", {})
         if node_type == NodeType.START:
             with Session(bind=db.engine) as session, session.begin():
                 draft_var_srv = WorkflowDraftVariableService(session)
@@ -335,7 +339,10 @@ class WorkflowService:
                     app=app_model,
                     workflow=draft_workflow,
                 )
-
+                start_data = StartNodeData.model_validate(node_data)
+                user_inputs = _rebuild_file_for_user_inputs_in_start_node(
+                    tenant_id=draft_workflow.tenant_id, start_node_data=start_data, user_inputs=user_inputs
+                )
                 # init variable pool
                 variable_pool = _setup_variable_pool(
                     query=query,
@@ -362,7 +369,6 @@ class WorkflowService:
             app_id=app_model.id,
         )
 
-        node_config = draft_workflow.get_node_config_by_id(node_id)
         eclosing_node_type_and_id = draft_workflow.get_enclosing_node_type_and_id(node_config)
         if eclosing_node_type_and_id:
             _, enclosing_node_id = eclosing_node_type_and_id
@@ -699,3 +705,36 @@ def _setup_variable_pool(
     )
 
     return variable_pool
+
+
+def _rebuild_file_for_user_inputs_in_start_node(
+    tenant_id: str, start_node_data: StartNodeData, user_inputs: Mapping[str, Any]
+) -> Mapping[str, Any]:
+    inputs_copy = dict(user_inputs)
+
+    for variable in start_node_data.variables:
+        if variable.type not in (VariableEntityType.FILE, VariableEntityType.FILE_LIST):
+            continue
+        if variable.variable not in user_inputs:
+            continue
+        value = user_inputs[variable.variable]
+        file = _rebuild_single_file(tenant_id=tenant_id, value=value, variable_entity_type=variable.type)
+        inputs_copy[variable.variable] = file
+    return inputs_copy
+
+
+def _rebuild_single_file(tenant_id: str, value: Any, variable_entity_type: VariableEntityType) -> File | Sequence[File]:
+    if variable_entity_type == VariableEntityType.FILE:
+        if not isinstance(value, dict):
+            raise ValueError(f"expected dict for file object, got {type(value)}")
+        return build_from_mapping(mapping=value, tenant_id=tenant_id)
+    elif variable_entity_type == VariableEntityType.FILE_LIST:
+        if not isinstance(value, list):
+            raise ValueError(f"expected list for file list object, got {type(value)}")
+        if len(value) == 0:
+            return []
+        if not isinstance(value[0], dict):
+            raise ValueError(f"expected dict for first element in the file list, got {type(value)}")
+        return build_from_mappings(mappings=value, tenant_id=tenant_id)
+    else:
+        raise Exception("unreachable")