fix: fix return empty array with STRUCT field [2.6] (#3074)

issue: milvus-io/milvus#42148
pr: #3073

Signed-off-by: SpadeA <tangchenjie1210@gmail.com>

Author: SpadeA-Tang

pymilvus/client/entity_helper.py

@@ -1017,57 +1017,69 @@ def check_append(field_data: Any, row_data: Dict):
 
 def get_array_length(array_item: Any) -> int:
     """Get the length of an array field from its data."""
-    if hasattr(array_item, "string_data") and array_item.string_data:
-        return len(array_item.string_data.data)
-    if hasattr(array_item, "int_data") and array_item.int_data:
-        return len(array_item.int_data.data)
-    if hasattr(array_item, "long_data") and array_item.long_data:
-        return len(array_item.long_data.data)
-    if hasattr(array_item, "float_data") and array_item.float_data:
-        return len(array_item.float_data.data)
-    if hasattr(array_item, "double_data") and array_item.double_data:
-        return len(array_item.double_data.data)
-    if hasattr(array_item, "bool_data") and array_item.bool_data:
-        return len(array_item.bool_data.data)
+    if hasattr(array_item, "string_data") and hasattr(array_item.string_data, "data"):
+        length = len(array_item.string_data.data)
+        if length > 0:
+            return length
+    if hasattr(array_item, "int_data") and hasattr(array_item.int_data, "data"):
+        length = len(array_item.int_data.data)
+        if length > 0:
+            return length
+    if hasattr(array_item, "long_data") and hasattr(array_item.long_data, "data"):
+        length = len(array_item.long_data.data)
+        if length > 0:
+            return length
+    if hasattr(array_item, "float_data") and hasattr(array_item.float_data, "data"):
+        length = len(array_item.float_data.data)
+        if length > 0:
+            return length
+    if hasattr(array_item, "double_data") and hasattr(array_item.double_data, "data"):
+        length = len(array_item.double_data.data)
+        if length > 0:
+            return length
+    if hasattr(array_item, "bool_data") and hasattr(array_item.bool_data, "data"):
+        length = len(array_item.bool_data.data)
+        if length > 0:
+            return length
     return 0
 
 
 def get_array_value_at_index(array_item: Any, idx: int) -> Any:
     """Get the value at a specific index from an array field."""
     if (
         hasattr(array_item, "string_data")
-        and array_item.string_data
-        and idx < len(array_item.string_data.data)
+        and hasattr(array_item.string_data, "data")
+        and len(array_item.string_data.data) > idx
     ):
         return array_item.string_data.data[idx]
     if (
         hasattr(array_item, "int_data")
-        and array_item.int_data
-        and idx < len(array_item.int_data.data)
+        and hasattr(array_item.int_data, "data")
+        and len(array_item.int_data.data) > idx
     ):
         return array_item.int_data.data[idx]
     if (
         hasattr(array_item, "long_data")
-        and array_item.long_data
-        and idx < len(array_item.long_data.data)
+        and hasattr(array_item.long_data, "data")
+        and len(array_item.long_data.data) > idx
     ):
         return array_item.long_data.data[idx]
     if (
         hasattr(array_item, "float_data")
-        and array_item.float_data
-        and idx < len(array_item.float_data.data)
+        and hasattr(array_item.float_data, "data")
+        and len(array_item.float_data.data) > idx
     ):
         return array_item.float_data.data[idx]
     if (
         hasattr(array_item, "double_data")
-        and array_item.double_data
-        and idx < len(array_item.double_data.data)
+        and hasattr(array_item.double_data, "data")
+        and len(array_item.double_data.data) > idx
     ):
         return array_item.double_data.data[idx]
     if (
         hasattr(array_item, "bool_data")
-        and array_item.bool_data
-        and idx < len(array_item.bool_data.data)
+        and hasattr(array_item.bool_data, "data")
+        and len(array_item.bool_data.data) > idx
     ):
         return array_item.bool_data.data[idx]
     return None