change of comparison report of 4 model update

app/models/manhole_domestic_chamber_model.py

@@ -1,5 +1,10 @@
 from app import db
 from datetime import datetime
+from sqlalchemy import event
+import re
+
+# REGEX PATTERN
+D_RANGE_PATTERN = re.compile(r"^d_\d+(?:_\d+)?_to_\d+(?:_\d+)?$")
 
 class ManholeDomesticChamber(db.Model):
     __tablename__ = "manhole_domestic_chamber"
@@ -27,7 +32,6 @@ class ManholeDomesticChamber(db.Model):
     d_4_16_to_4_65 = db.Column(db.Float)
     d_4_66_to_5_15 = db.Column(db.Float)
     d_5_16_to_5_65 = db.Column(db.Float)
-
     d_5_66_to_6_15 = db.Column(db.Float)
     d_6_16_to_6_65 = db.Column(db.Float)
     d_6_66_to_7_15 = db.Column(db.Float)
@@ -42,6 +46,7 @@ class ManholeDomesticChamber(db.Model):
     UPVC_Pipe_Length = db.Column(db.Float)
     RA_Bill_No=db.Column(db.String(500))
 
+    Total = db.Column(db.Float)
     created_at = db.Column(db.DateTime, default=datetime.today)
 
     def __repr__(self):
@@ -61,3 +66,18 @@ class ManholeDomesticChamber(db.Model):
             "d_7_66_to_8_15", "d_8_16_to_8_65", "d_8_66_to_9_15",
             "d_9_16_to_9_65"]
 
+# ===============================
+# AUTO TOTAL USING REGEX
+# ===============================
+def calculate_mh_dc_total(mapper, connection, target):
+    total = 0
+
+    for column in target.__table__.columns:
+        if D_RANGE_PATTERN.match(column.name):
+            total += getattr(target, column.name) or 0
+
+    target.Total = total
+
+
+event.listen(ManholeDomesticChamber, "before_insert", calculate_mh_dc_total)
+event.listen(ManholeDomesticChamber, "before_update", calculate_mh_dc_total)