change of comparison report of 4 model update

app/models/laying_model.py

@@ -1,5 +1,9 @@
 from app import db
 from datetime import datetime
+from sqlalchemy import event
+import re
+# REGEX PATTERN
+PIPE_MM_PATTERN = re.compile(r"^pipe_\d+_mm$")
 
 class Laying(db.Model):
     __tablename__ = "laying"
@@ -52,3 +56,18 @@ class Laying(db.Model):
             "pipe_450_mm", "pipe_500_mm", "pipe_600_mm",
             "pipe_700_mm", "pipe_900_mm", "pipe_1200_mm"
         ]
+
+# ===============================
+# AUTO TOTAL USING REGEX
+# ===============================
+def calculate_laying_total(mapper, connection, target):
+    total = 0
+
+    for column in target.__table__.columns:
+        if PIPE_MM_PATTERN.match(column.name):
+            total += getattr(target, column.name) or 0
+
+    target.Total = total
+
+event.listen(Laying, "before_insert", calculate_laying_total)
+event.listen(Laying, "before_update", calculate_laying_total)