From 501d3b6203b56f6df1a3dc5992e6f8e588f41615 Mon Sep 17 00:00:00 2001
From: QuantumGhost <obelisk.reg+git@gmail.com>
Date: Tue, 24 Jun 2025 20:27:22 +0800
Subject: [PATCH] feat(api): Explicitly define version method for all BaseNode
 subclasses (#21443)

This PR addresses issue #21441 by implementing explicit `version` method definitions for all `BaseNode` subclasses to improve code maintainability.

### Changes

Added explicit `version` method definitions for all `BaseNode` subclasses:

- `QuestionClassifierNode`
- `KnowledgeRetrievalNode`
- `AgentNode`

Added comprehensive test suite to validate:

1. All subclasses of `BaseNode` have explicitly defined `version` method
2. All subclasses have required `_node_type` property
3. The `(node_type, node_version)` combination is unique across all subclasses
---
 api/core/workflow/nodes/agent/agent_node.py   |  4 +++
 .../knowledge_retrieval_node.py               |  4 +++
 .../question_classifier_node.py               |  4 +++
 .../workflow/nodes/base/test_base_node.py     | 36 +++++++++++++++++++
 4 files changed, 48 insertions(+)
 create mode 100644 api/tests/unit_tests/core/workflow/nodes/base/test_base_node.py

diff --git a/api/core/workflow/nodes/agent/agent_node.py b/api/core/workflow/nodes/agent/agent_node.py
index 22c564c1fc..2f28363955 100644
--- a/api/core/workflow/nodes/agent/agent_node.py
+++ b/api/core/workflow/nodes/agent/agent_node.py
@@ -39,6 +39,10 @@ class AgentNode(ToolNode):
     _node_data_cls = AgentNodeData  # type: ignore
     _node_type = NodeType.AGENT
 
+    @classmethod
+    def version(cls) -> str:
+        return "1"
+
     def _run(self) -> Generator:
         """
         Run the agent node
diff --git a/api/core/workflow/nodes/knowledge_retrieval/knowledge_retrieval_node.py b/api/core/workflow/nodes/knowledge_retrieval/knowledge_retrieval_node.py
index 2995f0682f..0b9e98f28a 100644
--- a/api/core/workflow/nodes/knowledge_retrieval/knowledge_retrieval_node.py
+++ b/api/core/workflow/nodes/knowledge_retrieval/knowledge_retrieval_node.py
@@ -71,6 +71,10 @@ class KnowledgeRetrievalNode(LLMNode):
     _node_data_cls = KnowledgeRetrievalNodeData  # type: ignore
     _node_type = NodeType.KNOWLEDGE_RETRIEVAL
 
+    @classmethod
+    def version(cls):
+        return "1"
+
     def _run(self) -> NodeRunResult:  # type: ignore
         node_data = cast(KnowledgeRetrievalNodeData, self.node_data)
         # extract variables
diff --git a/api/core/workflow/nodes/question_classifier/question_classifier_node.py b/api/core/workflow/nodes/question_classifier/question_classifier_node.py
index 1f50700c7e..a518167cc6 100644
--- a/api/core/workflow/nodes/question_classifier/question_classifier_node.py
+++ b/api/core/workflow/nodes/question_classifier/question_classifier_node.py
@@ -40,6 +40,10 @@ class QuestionClassifierNode(LLMNode):
     _node_data_cls = QuestionClassifierNodeData  # type: ignore
     _node_type = NodeType.QUESTION_CLASSIFIER
 
+    @classmethod
+    def version(cls):
+        return "1"
+
     def _run(self):
         node_data = cast(QuestionClassifierNodeData, self.node_data)
         variable_pool = self.graph_runtime_state.variable_pool
diff --git a/api/tests/unit_tests/core/workflow/nodes/base/test_base_node.py b/api/tests/unit_tests/core/workflow/nodes/base/test_base_node.py
new file mode 100644
index 0000000000..8712b61a23
--- /dev/null
+++ b/api/tests/unit_tests/core/workflow/nodes/base/test_base_node.py
@@ -0,0 +1,36 @@
+from core.workflow.nodes.base.node import BaseNode
+from core.workflow.nodes.enums import NodeType
+
+# Ensures that all node classes are imported.
+from core.workflow.nodes.node_mapping import NODE_TYPE_CLASSES_MAPPING
+
+_ = NODE_TYPE_CLASSES_MAPPING
+
+
+def _get_all_subclasses(root: type[BaseNode]) -> list[type[BaseNode]]:
+    subclasses = []
+    queue = [root]
+    while queue:
+        cls = queue.pop()
+
+        subclasses.extend(cls.__subclasses__())
+        queue.extend(cls.__subclasses__())
+
+    return subclasses
+
+
+def test_ensure_subclasses_of_base_node_has_node_type_and_version_method_defined():
+    classes = _get_all_subclasses(BaseNode)  # type: ignore
+    type_version_set: set[tuple[NodeType, str]] = set()
+
+    for cls in classes:
+        # Validate that 'version' is directly defined in the class (not inherited) by checking the class's __dict__
+        assert "version" in cls.__dict__, f"class {cls} should have version method defined (NOT INHERITED.)"
+        node_type = cls._node_type
+        node_version = cls.version()
+
+        assert isinstance(cls._node_type, NodeType)
+        assert isinstance(node_version, str)
+        node_type_and_version = (node_type, node_version)
+        assert node_type_and_version not in type_version_set
+        type_version_set.add(node_type_and_version)