Validation of brand tags (#145)

* Added Brand Tag validation on Save to allow only alpha-numerical characters, underscores and dashes

* Tag Validation. Only alpha-numeric characters, underscore and dash are allowed. When there is an error, the form does not get submitted, the error message is displayed near the Ta
g field. Tests are also completed.

* reformatting with black

* added 'http://' to the website link so that the tests passed

brand/models/brand.py

@@ -4,6 +4,7 @@
 from django.db import models
 from django.db.models.query import QuerySet
 from django.template.defaultfilters import truncatechars
+from django.core.exceptions import ValidationError
 
 from cities_light.models import Region, SubRegion
 from django_countries.fields import CountryField
@@ -16,6 +17,16 @@
 # from Levenshtein import distance as lev
 
 
+def validate_tag(value):
+    """This is the function that is used to validate the TAG"""
+    if re.match("^[A-Za-z0-9_-]*$", str(value)):
+        return value
+    else:
+        raise ValidationError(
+            "Tag can contain only alpha-numeric characters, underscores and dashes"
+        )
+
+
 class Brand(TimeStampedModel):
     """
     A "Brand" is the instance shown to the end user.
@@ -68,6 +79,7 @@ def short_tag(self):
         editable=True,
         unique=True,
         help_text="the tag we use or this brand record at Bank.Green. ",
+        validators=[validate_tag],
     )
     tag_locked = models.BooleanField(default=True)
 
@@ -318,3 +330,7 @@ def create_spelling_dictionary(cls):
         }
 
         return spelling_dict
+
+    def save(self, *args, **kwargs):
+        self.full_clean()
+        return super().save(*args, **kwargs)

brand/tests/test.py

@@ -195,3 +195,25 @@ def test_compute_inherited_rating_circular_path_can_return_unknown(self):
         self.assertEqual(
             self.commentary5.compute_inherited_rating(throw_error=False), RatingChoice.UNKNOWN
         )
+
+
+class BrandTagTestCase(TestCase):
+    # test for a Valid Tag
+    def test_brand_valid_tag(self):
+        brand1 = Brand(name="Test Brand 1", tag="Tag_Brand-1")
+        # this should not raise any errors
+        brand1.save()
+
+    # test for an Invalid Tags
+    def test_brand_invalid_tag(self):
+        # test case with not allowed characters
+        brand1 = Brand(name="Test Brand 1", tag="TagBrand%$1")
+
+        with self.assertRaises(ValidationError):
+            brand1.save()
+
+        # test case with the spaces
+        brand1 = Brand(name="Test Brand 1", tag="Tag Brand 1")
+
+        with self.assertRaises(ValidationError):
+            brand1.save()

brand/tests/utils.py

@@ -7,7 +7,7 @@ def create_test_brands():
         tag="test_brand_1",
         name="Test Brand 1",
         aliases="test brand, testb",
-        website="www.testbrand.com",
+        website="http://www.testbrand.com",
         permid="test permid",
         viafid="test viafid",
         lei="test lei",