fix: iteration node use the main thread pool

api/core/workflow/nodes/iteration/iteration_node.py

@@ -116,7 +116,7 @@ class IterationNode(BaseNode[IterationNodeData]):
         variable_pool.add([self.node_id, "item"], iterator_list_value[0])
 
         # init graph engine
-        from core.workflow.graph_engine.graph_engine import GraphEngine, GraphEngineThreadPool
+        from core.workflow.graph_engine.graph_engine import GraphEngine
 
         graph_engine = GraphEngine(
             tenant_id=self.tenant_id,

api/libs/helper.py

@@ -10,10 +10,10 @@ from collections.abc import Generator, Mapping
 from datetime import datetime
 from hashlib import sha256
 from typing import Any, Optional, Union
-from zoneinfo import available_timezones
 
 from flask import Response, stream_with_context
 from flask_restful import fields
+from zoneinfo import available_timezones
 
 from configs import dify_config
 from core.app.features.rate_limiting.rate_limit import RateLimitGenerator