refactor: strip external imports in workflow template transform (#32017)

api/.importlinter

@@ -136,7 +136,6 @@ ignore_imports =
     core.workflow.nodes.llm.llm_utils -> models.provider
     core.workflow.nodes.llm.llm_utils -> services.credit_pool_service
     core.workflow.nodes.llm.node -> core.tools.signature
-    core.workflow.nodes.template_transform.template_transform_node -> configs
     core.workflow.nodes.tool.tool_node -> core.callback_handler.workflow_tool_callback_handler
     core.workflow.nodes.tool.tool_node -> core.tools.tool_engine
     core.workflow.nodes.tool.tool_node -> core.tools.tool_manager

api/core/app/workflow/node_factory.py

@@ -47,6 +47,7 @@ class DifyNodeFactory(NodeFactory):
         code_providers: Sequence[type[CodeNodeProvider]] | None = None,
         code_limits: CodeNodeLimits | None = None,
         template_renderer: Jinja2TemplateRenderer | None = None,
+        template_transform_max_output_length: int | None = None,
         http_request_http_client: HttpClientProtocol | None = None,
         http_request_tool_file_manager_factory: Callable[[], ToolFileManager] = ToolFileManager,
         http_request_file_manager: FileManagerProtocol | None = None,
@@ -68,6 +69,9 @@ class DifyNodeFactory(NodeFactory):
             max_object_array_length=dify_config.CODE_MAX_OBJECT_ARRAY_LENGTH,
         )
         self._template_renderer = template_renderer or CodeExecutorJinja2TemplateRenderer()
+        self._template_transform_max_output_length = (
+            template_transform_max_output_length or dify_config.TEMPLATE_TRANSFORM_MAX_LENGTH
+        )
         self._http_request_http_client = http_request_http_client or ssrf_proxy
         self._http_request_tool_file_manager_factory = http_request_tool_file_manager_factory
         self._http_request_file_manager = http_request_file_manager or file_manager
@@ -122,6 +126,7 @@ class DifyNodeFactory(NodeFactory):
                 graph_init_params=self.graph_init_params,
                 graph_runtime_state=self.graph_runtime_state,
                 template_renderer=self._template_renderer,
+                max_output_length=self._template_transform_max_output_length,
             )
 
         if node_type == NodeType.HTTP_REQUEST:

api/core/workflow/nodes/template_transform/template_transform_node.py

@@ -1,7 +1,6 @@
 from collections.abc import Mapping, Sequence
 from typing import TYPE_CHECKING, Any
 
-from configs import dify_config
 from core.workflow.enums import NodeType, WorkflowNodeExecutionStatus
 from core.workflow.node_events import NodeRunResult
 from core.workflow.nodes.base.node import Node
@@ -16,12 +15,13 @@ if TYPE_CHECKING:
     from core.workflow.entities import GraphInitParams
     from core.workflow.runtime import GraphRuntimeState
 
-MAX_TEMPLATE_TRANSFORM_OUTPUT_LENGTH = dify_config.TEMPLATE_TRANSFORM_MAX_LENGTH
+DEFAULT_TEMPLATE_TRANSFORM_MAX_OUTPUT_LENGTH = 400_000
 
 
 class TemplateTransformNode(Node[TemplateTransformNodeData]):
     node_type = NodeType.TEMPLATE_TRANSFORM
     _template_renderer: Jinja2TemplateRenderer
+    _max_output_length: int
 
     def __init__(
         self,
@@ -31,6 +31,7 @@ class TemplateTransformNode(Node[TemplateTransformNodeData]):
         graph_runtime_state: "GraphRuntimeState",
         *,
         template_renderer: Jinja2TemplateRenderer | None = None,
+        max_output_length: int | None = None,
     ) -> None:
         super().__init__(
             id=id,
@@ -40,6 +41,10 @@ class TemplateTransformNode(Node[TemplateTransformNodeData]):
         )
         self._template_renderer = template_renderer or CodeExecutorJinja2TemplateRenderer()
 
+        if max_output_length is not None and max_output_length <= 0:
+            raise ValueError("max_output_length must be a positive integer")
+        self._max_output_length = max_output_length or DEFAULT_TEMPLATE_TRANSFORM_MAX_OUTPUT_LENGTH
+
     @classmethod
     def get_default_config(cls, filters: Mapping[str, object] | None = None) -> Mapping[str, object]:
         """
@@ -69,11 +74,11 @@ class TemplateTransformNode(Node[TemplateTransformNodeData]):
         except TemplateRenderError as e:
             return NodeRunResult(inputs=variables, status=WorkflowNodeExecutionStatus.FAILED, error=str(e))
 
-        if len(rendered) > MAX_TEMPLATE_TRANSFORM_OUTPUT_LENGTH:
+        if len(rendered) > self._max_output_length:
             return NodeRunResult(
                 inputs=variables,
                 status=WorkflowNodeExecutionStatus.FAILED,
-                error=f"Output length exceeds {MAX_TEMPLATE_TRANSFORM_OUTPUT_LENGTH} characters",
+                error=f"Output length exceeds {self._max_output_length} characters",
             )
 
         return NodeRunResult(

api/tests/unit_tests/core/workflow/nodes/template_transform/template_transform_node_spec.py

@@ -217,7 +217,6 @@ class TestTemplateTransformNode:
     @patch(
         "core.workflow.nodes.template_transform.template_transform_node.CodeExecutorJinja2TemplateRenderer.render_template"
     )
-    @patch("core.workflow.nodes.template_transform.template_transform_node.MAX_TEMPLATE_TRANSFORM_OUTPUT_LENGTH", 10)
     def test_run_output_length_exceeds_limit(
         self, mock_execute, basic_node_data, mock_graph, mock_graph_runtime_state, graph_init_params
     ):
@@ -231,6 +230,7 @@ class TestTemplateTransformNode:
             graph_init_params=graph_init_params,
             graph=mock_graph,
             graph_runtime_state=mock_graph_runtime_state,
+            max_output_length=10,
         )
 
         result = node._run()