[IMP] Chapter 10: Constraints

Added SQL constraints for expected_price, selling_price, property_tag_name and property_type_name

Added python constraint for selling_price to be >= 90% of expected_price unless it is 0.0

Author: SurryaT10

estate/models/estate.py

@@ -1,5 +1,6 @@
 from odoo import api, fields, models
-from odoo.exceptions import UserError
+from odoo.exceptions import UserError, ValidationError
+from odoo.tools.float_utils import float_compare, float_is_zero
 
 
 class Estate(models.Model):
@@ -74,3 +75,20 @@ def action_mark_cancel(self):
             if record.status == 'sold':
                 raise UserError("Sold properties cannot be canceled.")
             record.status = 'canceled'
+
+    _check_expected_price = models.Constraint(
+        'CHECK(expected_price > 0)',
+        'The expected price must be strictly positive'
+    )
+
+    _check_selling_price = models.Constraint(
+        'CHECK(selling_price >= 0)',
+        'The selling price must be positive'
+    )
+
+    @api.constrains('selling_price')
+    def _check_selling_price(self):
+        for record in self:
+            if not float_is_zero(record.selling_price, precision_digits=2):
+                if float_compare(record.selling_price, record.expected_price * 0.9, precision_digits=2) < 0:
+                    raise ValidationError('The selling price must be atleast 90% of the expected price! You must reduce the expected price to accept the offer')

estate/models/offer.py

@@ -45,3 +45,7 @@ def action_reject_offer(self):
                 record.property_id.buyer_id = False
                 record.property_id.status = 'offer_received'
 
+    _check_price = models.Constraint(
+        'CHECK(price > 0)',
+        'The offer price must be strictly positive'
+    )

estate/models/property_tag.py

@@ -6,3 +6,8 @@ class PropertyTag(models.Model):
     _description = 'Estate Property Tag'
 
     name = fields.Char("Tag Name", required=True)
+
+    _unique_name = models.Constraint(
+        'UNIQUE(name)',
+        'The property tag name must be unique'
+    )

estate/models/property_type.py

@@ -6,3 +6,8 @@ class PropertyType(models.Model):
     _description = 'Estate Property Type'
 
     name = fields.Char("Property Type", required=True)
+
+    _unique_name = models.Constraint(
+        'UNIQUE(name)',
+        'The property type name must be unique'
+    )