From 02fdc5e2a47c176f68863229166ffe36fd263080 Mon Sep 17 00:00:00 2001
From: kinglisky <free.nan.sky@gmail.com>
Date: Fri, 5 Dec 2025 15:27:18 +0800
Subject: [PATCH] fix: Variable Assigner node silently fails for legacy V1 data
 format (#28867)

---
 api/core/workflow/nodes/node_factory.py       |  5 +++-
 .../v1/test_variable_assigner_v1.py           | 24 ++++++++++++++++---
 .../v2/test_variable_assigner_v2.py           |  8 +++----
 3 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/api/core/workflow/nodes/node_factory.py b/api/core/workflow/nodes/node_factory.py
index 5fc363257b..c55ad346bf 100644
--- a/api/core/workflow/nodes/node_factory.py
+++ b/api/core/workflow/nodes/node_factory.py
@@ -64,7 +64,10 @@ class DifyNodeFactory(NodeFactory):
         if not node_mapping:
             raise ValueError(f"No class mapping found for node type: {node_type}")
 
-        node_class = node_mapping.get(LATEST_VERSION)
+        latest_node_class = node_mapping.get(LATEST_VERSION)
+        node_version = str(node_data.get("version", "1"))
+        matched_node_class = node_mapping.get(node_version)
+        node_class = matched_node_class or latest_node_class
         if not node_class:
             raise ValueError(f"No latest version class found for node type: {node_type}")
 
diff --git a/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v1/test_variable_assigner_v1.py b/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v1/test_variable_assigner_v1.py
index ef23a8f565..c62fc4d8fe 100644
--- a/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v1/test_variable_assigner_v1.py
+++ b/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v1/test_variable_assigner_v1.py
@@ -30,7 +30,13 @@ def test_overwrite_string_variable():
         "nodes": [
             {"data": {"type": "start", "title": "Start"}, "id": "start"},
             {
-                "data": {"type": "assigner", "version": "1", "title": "Variable Assigner", "items": []},
+                "data": {
+                    "type": "assigner",
+                    "title": "Variable Assigner",
+                    "assigned_variable_selector": ["conversation", "test_conversation_variable"],
+                    "write_mode": "over-write",
+                    "input_variable_selector": ["node_id", "test_string_variable"],
+                },
                 "id": "assigner",
             },
         ],
@@ -131,7 +137,13 @@ def test_append_variable_to_array():
         "nodes": [
             {"data": {"type": "start", "title": "Start"}, "id": "start"},
             {
-                "data": {"type": "assigner", "version": "1", "title": "Variable Assigner", "items": []},
+                "data": {
+                    "type": "assigner",
+                    "title": "Variable Assigner",
+                    "assigned_variable_selector": ["conversation", "test_conversation_variable"],
+                    "write_mode": "append",
+                    "input_variable_selector": ["node_id", "test_string_variable"],
+                },
                 "id": "assigner",
             },
         ],
@@ -231,7 +243,13 @@ def test_clear_array():
         "nodes": [
             {"data": {"type": "start", "title": "Start"}, "id": "start"},
             {
-                "data": {"type": "assigner", "version": "1", "title": "Variable Assigner", "items": []},
+                "data": {
+                    "type": "assigner",
+                    "title": "Variable Assigner",
+                    "assigned_variable_selector": ["conversation", "test_conversation_variable"],
+                    "write_mode": "clear",
+                    "input_variable_selector": [],
+                },
                 "id": "assigner",
             },
         ],
diff --git a/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v2/test_variable_assigner_v2.py b/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v2/test_variable_assigner_v2.py
index f793341e73..caa36734ad 100644
--- a/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v2/test_variable_assigner_v2.py
+++ b/api/tests/unit_tests/core/workflow/nodes/variable_assigner/v2/test_variable_assigner_v2.py
@@ -78,7 +78,7 @@ def test_remove_first_from_array():
         "nodes": [
             {"data": {"type": "start", "title": "Start"}, "id": "start"},
             {
-                "data": {"type": "assigner", "title": "Variable Assigner", "items": []},
+                "data": {"type": "assigner", "version": "2", "title": "Variable Assigner", "items": []},
                 "id": "assigner",
             },
         ],
@@ -162,7 +162,7 @@ def test_remove_last_from_array():
         "nodes": [
             {"data": {"type": "start", "title": "Start"}, "id": "start"},
             {
-                "data": {"type": "assigner", "title": "Variable Assigner", "items": []},
+                "data": {"type": "assigner", "version": "2", "title": "Variable Assigner", "items": []},
                 "id": "assigner",
             },
         ],
@@ -243,7 +243,7 @@ def test_remove_first_from_empty_array():
         "nodes": [
             {"data": {"type": "start", "title": "Start"}, "id": "start"},
             {
-                "data": {"type": "assigner", "title": "Variable Assigner", "items": []},
+                "data": {"type": "assigner", "version": "2", "title": "Variable Assigner", "items": []},
                 "id": "assigner",
             },
         ],
@@ -324,7 +324,7 @@ def test_remove_last_from_empty_array():
         "nodes": [
             {"data": {"type": "start", "title": "Start"}, "id": "start"},
             {
-                "data": {"type": "assigner", "title": "Variable Assigner", "items": []},
+                "data": {"type": "assigner", "version": "2", "title": "Variable Assigner", "items": []},
                 "id": "assigner",
             },
         ],