fix #37 - send email when askers' bids are met

auctions/migrations/0003_bid_ask_match_sent.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('auctions', '0002_auto_20141005_0226'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='bid',
+            name='ask_match_sent',
+            field=models.BooleanField(default=False),
+            preserve_default=True,
+        ),
+    ]

auctions/models.py

@@ -1,9 +1,32 @@
 from django.conf import settings
 from django.db import models
+from django.db.models import Sum
+from django.db.models.signals import post_save
+from django.dispatch import receiver
+
+from mailer import send_mail
 
 
 class Bid(models.Model):
     user = models.ForeignKey(settings.AUTH_USER_MODEL)
     url = models.URLField()
     ask = models.DecimalField(max_digits=6, decimal_places=2)
+    ask_match_sent = models.BooleanField(default=False)
     offer = models.DecimalField(max_digits=6, decimal_places=2)
+
+
+@receiver(post_save, sender=Bid)
+def notify_matching_askers(sender, instance, **kwargs):
+    issue_bids = Bid.objects.filter(url=instance.url).aggregate(Sum('offer'))
+    met_asks = (Bid.objects.filter(url=instance.url,
+                                   ask__lte=issue_bids['offer__sum'],
+                                   ask_match_sent=False)
+                           .exclude(ask__lte=0))
+    for bid in met_asks:
+        send_mail("[codesy] Your ask for %(ask)d for %(url)s has been met" % (
+            {'ask': bid.ask, 'url': bid.url}),
+            "Bidders have met your asking price for %s." % bid.url,
+            settings.DEFAULT_FROM_EMAIL,
+            [bid.user.email])
+        # use .update to avoid recursive signal processing
+        Bid.objects.filter(id=bid.id).update(ask_match_sent=True)

auctions/tests/model_tests.py

@@ -0,0 +1,64 @@
+import fudge
+
+from django.conf import settings
+from django.test import TestCase
+
+from model_mommy import mommy
+
+
+class NotifyMatchersReceiverTest(TestCase):
+    def setUp(self):
+        """
+        Set up the following market of Bids for a single bug:
+            user1: ask 50,  offer 0
+            user2: ask 100, offer 10
+            user3: ask 0,   offer 30
+        """
+        self.url = 'http://github.com/codesy/codesy/issues/37'
+        self.bid1 = mommy.make('auctions.Bid', user__email='user1@test.com',
+                               ask=50, offer=0, url=self.url)
+        self.bid2 = mommy.make('auctions.Bid', user__email='user2@test.com',
+                               ask=100, offer=10, url=self.url)
+        self.bid3 = mommy.make('auctions.Bid', user__email='user3@test.com',
+                               ask=0, offer=30, url=self.url)
+
+    def _add_url(self, string):
+        return string.format(url=self.url)
+
+    @fudge.patch('auctions.models.send_mail')
+    def test_send_mail_to_matching_askers(self, mock_send_mail):
+        user = mommy.make(settings.AUTH_USER_MODEL)
+
+        mock_send_mail.expects_call().with_args(
+            self._add_url('[codesy] Your ask for 50 for {url} has been met'),
+            self._add_url('Bidders have met your asking price for {url}.'),
+            settings.DEFAULT_FROM_EMAIL,
+            ['user1@test.com']
+        )
+        mock_send_mail.next_call().with_args(
+            self._add_url('[codesy] Your ask for 100 for {url} has been met'),
+            self._add_url('Bidders have met your asking price for {url}.'),
+            settings.DEFAULT_FROM_EMAIL,
+            ['user2@test.com']
+        )
+
+        offer_bid = mommy.prepare(
+            'auctions.Bid', offer=100, user=user, ask=1000, url=self.url)
+        offer_bid.save()
+
+    @fudge.patch('auctions.models.send_mail')
+    def test_only_send_mail_to_unsent_matching_askers(self, mock_send_mail):
+        user = mommy.make(settings.AUTH_USER_MODEL)
+        self.bid1.ask_match_sent = True
+        self.bid1.save()
+
+        mock_send_mail.expects_call().with_args(
+            self._add_url('[codesy] Your ask for 100 for {url} has been met'),
+            self._add_url('Bidders have met your asking price for {url}.'),
+            settings.DEFAULT_FROM_EMAIL,
+            ['user2@test.com']
+        )
+
+        offer_bid = mommy.prepare(
+            'auctions.Bid', offer=100, user=user, ask=1000, url=self.url)
+        offer_bid.save()

codesy/settings.py

@@ -44,6 +44,7 @@
     'allauth.account',
     'allauth.socialaccount',
     'allauth.socialaccount.providers.github',
+    'mailer',
     'rest_framework',
     'rest_framework_swagger'
 )

requirements.txt

@@ -2,6 +2,7 @@ Django==1.7.1
 dj-database-url==0.3.0
 dj-static==0.0.6
 django-allauth==0.18.0
+django-mailer==0.1.0
 django-toolbelt==0.0.1
 django-rest-swagger==0.2.0
 djangorestframework==2.4.4