models: Fix the URL validation code in `RealmFilter` model.

zerver/migrations/0094_realm_filter_url_validator.py

@@ -0,0 +1,22 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.2 on 2017-07-22 13:44
+from __future__ import unicode_literals
+
+import django.core.validators
+from django.db import migrations, models
+import zerver.models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('zerver', '0093_subscription_event_log_backfill'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='realmfilter',
+            name='url_format_string',
+            field=models.TextField(validators=[django.core.validators.URLValidator(), zerver.models.filter_format_validator]),
+        ),
+    ]

zerver/models.py

@@ -468,7 +468,7 @@ def filter_format_validator(value):
 class RealmFilter(models.Model):
     realm = models.ForeignKey(Realm, on_delete=CASCADE)  # type: Realm
     pattern = models.TextField(validators=[filter_pattern_validator])  # type: Text
-    url_format_string = models.TextField(validators=[URLValidator, filter_format_validator])  # type: Text
+    url_format_string = models.TextField(validators=[URLValidator(), filter_format_validator])  # type: Text
 
     class Meta(object):
         unique_together = ("realm", "pattern")

zerver/tests/test_realm_filters.py

@@ -43,6 +43,11 @@ class RealmFilterTest(ZulipTestCase):
         data['pattern'] = 'ZUL-(?P<id>\d+)'
         data['url_format_string'] = '$fgfg'
         result = self.client_post("/json/realm/filters", info=data)
+        self.assert_json_error(result, 'Enter a valid URL.')
+
+        data['pattern'] = 'ZUL-(?P<id>\d+)'
+        data['url_format_string'] = 'https://realm.com/my_realm_filter/'
+        result = self.client_post("/json/realm/filters", info=data)
         self.assert_json_error(result, 'URL format string must be in the following format: `https://example.com/%(\\w+)s`')
 
         data['url_format_string'] = 'https://realm.com/my_realm_filter/%(id)s'