Create notification model

app/migrations/0014_notification_followers.py

@@ -0,0 +1,44 @@
+# Generated by Django 3.0.10 on 2020-09-19 22:58
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('contenttypes', '0002_remove_content_type_name'),
+        ('app', '0013_auto_20200919_0144'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Notification',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('message', models.CharField(help_text='Notification message.', max_length=255, verbose_name='Message')),
+                ('object_id', models.PositiveIntegerField(null=True, verbose_name='Linked Item ID')),
+                ('created', models.DateField(auto_now_add=True, help_text='Date this notification was sent.', verbose_name='Creation Date')),
+                ('content_type', models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, to='contenttypes.ContentType', verbose_name='Linked Item Type')),
+            ],
+        ),
+        migrations.AddField(
+            model_name='challenge',
+            name='followers',
+            field=models.ManyToManyField(help_text='Followers of this project who will receive notifications about it.', related_name='followed_challenges', to='app.Profile', verbose_name='Followers'),
+        ),
+        migrations.AddField(
+            model_name='project',
+            name='followers',
+            field=models.ManyToManyField(help_text='Followers of this project who will receive notifications about it.', related_name='followed_projects', to='app.Profile', verbose_name='Followers'),
+        ),
+        migrations.CreateModel(
+            name='NotificationInstance',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('is_read', models.BooleanField(default=False, help_text='Whether this notification has been read.', verbose_name='Is Read')),
+                ('notification', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='notifications', to='app.Notification')),
+                ('user', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='notifications', to='app.Profile')),
+            ],
+        ),
+    ]

app/models.py

@@ -137,6 +137,12 @@ class Challenge(models.Model):
         help_text="Creators of this challenge which can edit its properties. Removing yourself "
         + "will make it impossible to edit this challenge.",
     )
+    followers = models.ManyToManyField(
+        Profile,
+        related_name="followed_challenges",
+        verbose_name="Followers",
+        help_text="Followers of this project who will receive notifications about it.",
+    )
     created = models.DateField(
         auto_now_add=True,
         verbose_name="Creation Date",
@@ -235,6 +241,12 @@ class Project(models.Model):
         help_text="Creators of this project which can edit its properties. Removing yourself will "
         + "make it impossible for you to edit this project.",
     )
+    followers = models.ManyToManyField(
+        Profile,
+        related_name="followed_projects",
+        verbose_name="Followers",
+        help_text="Followers of this project who will receive notifications about it.",
+    )
     created = models.DateField(
         auto_now_add=True, verbose_name="Creation Date", help_text="Date this project was created."
     )
@@ -270,3 +282,34 @@ def __str__(self):
 def create_profile(sender, instance, created, **kwargs):
     if created:
         Profile.objects.create(user=instance)
+
+
+class Notification(models.Model):
+    message = models.CharField(
+        max_length=255, verbose_name="Message", help_text="Notification message."
+    )
+    content_type = models.ForeignKey(
+        ContentType, null=True, verbose_name="Linked Item Type", on_delete=models.CASCADE
+    )
+    object_id = models.PositiveIntegerField(null=True, verbose_name="Linked Item ID")
+    linked_item = GenericForeignKey()
+    created = models.DateField(
+        auto_now_add=True,
+        verbose_name="Creation Date",
+        help_text="Date this notification was sent.",
+    )
+
+    def get_link_url(self):
+        if self.linked_item:
+            return self.linked_item.get_absolute_url()
+        return "#"
+
+
+class NotificationInstance(models.Model):
+    notification = models.ForeignKey(
+        Notification, related_name="notifications", on_delete=models.CASCADE
+    )
+    user = models.ForeignKey(Profile, related_name="notifications", on_delete=models.CASCADE)
+    is_read = models.BooleanField(
+        default=False, verbose_name="Is Read", help_text="Whether this notification has been read."
+    )