Add the product and product images models

.pre-commit-config.yaml

@@ -1,13 +1,9 @@
 # See https://pre-commit.com for more information
 # See https://pre-commit.com/hooks.html for more hooks
 repos:
--   repo: https://github.com/pre-commit/pre-commit-hooks
+  - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v2.4.0
     hooks:
-    -   id: trailing-whitespace
-    -   id: end-of-file-fixer
-    -   id: check-added-large-files
--   repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v0.782
-    hooks:
-    -   id: mypy
+      - id: trailing-whitespace
+      - id: end-of-file-fixer
+      - id: check-added-large-files

Pipfile

@@ -9,13 +9,14 @@ factory-boy = "*"
 [packages]
 django = "==3.0.7"
 psycopg2 = "==2.8.5"
-django-environ = "*"
 django-extensions = "==3.0.2"
 pydotplus = "*"
-ipython = "*"
 werkzeug = "*"
 pre-commit = "*"
 django-registration = "==3.1"
+pillow = "*"
+ipython = "*"
+django-environ = "*"
 
 [requires]
 python_version = "3.8"

config/settings.py

@@ -24,8 +24,8 @@
 # Application definition
 
 INSTALLED_APPS = [
-    'user',
-    'main',
+    'main.apps.MainConfig',
+    'user.apps.UserConfig',
     'django_registration',
     'django.contrib.admin',
     'django.contrib.auth',

main/admin.py

@@ -1,3 +1,6 @@
 from django.contrib import admin
 
-# Register your models here.
+from main.models import Product, ProductImage
+
+admin.site.register(Product)
+admin.site.register(ProductImage)

main/apps.py

@@ -3,3 +3,6 @@
 
 class MainConfig(AppConfig):
     name = 'main'
+
+    def ready(self):
+        import main.signals

main/migrations/0001_initial.py

@@ -0,0 +1,27 @@
+# Generated by Django 3.0.7 on 2020-09-26 15:32
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    initial = True
+
+    dependencies = [
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Product',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=60, verbose_name='Name')),
+                ('description', models.CharField(blank=True, max_length=255, null=True, verbose_name='Description')),
+                ('site', models.CharField(max_length=60, verbose_name='Site')),
+                ('active', models.BooleanField(default=True, verbose_name='Active')),
+                ('product_code', models.CharField(blank=True, max_length=60, null=True, verbose_name='Product code')),
+                ('date_updated', models.DateTimeField(auto_now=True)),
+                ('date_created', models.DateTimeField(auto_now_add=True)),
+            ],
+        ),
+    ]

main/migrations/0002_productimage.py

@@ -0,0 +1,23 @@
+# Generated by Django 3.0.7 on 2020-09-26 16:34
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('main', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='ProductImage',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('image', models.ImageField(upload_to='product-images')),
+                ('thumbnail', models.ImageField(null=True, upload_to='product-thumbnails')),
+                ('product', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='main.Product')),
+            ],
+        ),
+    ]

main/models.py

@@ -1,3 +1,24 @@
 from django.db import models
 
-# Create your models here.
+
+class ProductManager(models.Manager):
+    def active(self):
+        return self.filter(active=True)
+
+
+class Product(models.Model):
+    name = models.CharField('Name', null=False, blank=False, max_length=60)
+    description = models.CharField('Description', null=True, blank=True, max_length=255)
+    site = models.CharField('Site', null=False, blank=False, max_length=60)
+    active = models.BooleanField('Active', null=False, default=True)
+    product_code = models.CharField('Product code', null=True, blank=True, max_length=60)
+    date_updated = models.DateTimeField(auto_now=True)
+    date_created = models.DateTimeField(auto_now_add=True, null=False)
+
+    objects = ProductManager()
+
+
+class ProductImage(models.Model):
+    product = models.ForeignKey(Product, on_delete=models.CASCADE)
+    image = models.ImageField(upload_to='product-images')
+    thumbnail = models.ImageField(upload_to='product-thumbnails', null=True, blank=True)

main/signals.py

@@ -0,0 +1,32 @@
+import logging
+from io import BytesIO
+
+from PIL import Image
+from django.core.files.base import ContentFile
+from django.db.models.signals import pre_save
+from django.dispatch import receiver
+
+from main.models import ProductImage
+
+THUMBNAIL_SIZE = (300, 300)
+logger = logging.getLogger(__name__)
+
+
+@receiver(pre_save, sender=ProductImage)
+def generate_thumbnail(sender, instance, **kwargs):
+    logger.info('Generating thumbnail for product %d', instance.product.id)
+    image = Image.open(instance.image)
+    image = image.convert('RGB')
+    image.thumbnail(THUMBNAIL_SIZE, Image.ANTIALIAS)
+
+    temp_thumb = BytesIO()
+    image.save(temp_thumb, 'JPEG')
+    temp_thumb.seek(0)
+
+    # set save=False, otherwise it will run in an infinite loop
+    instance.thumbnail.save(
+        instance.image.name,
+        ContentFile(temp_thumb.read()),
+        save=False,
+    )
+    temp_thumb.close()

main/tests/factories.py

@@ -0,0 +1,13 @@
+import factory.fuzzy
+
+from main import models
+
+
+class ProductFactory(factory.django.DjangoModelFactory):
+    name = factory.Sequence(lambda x: f'Product {x}')
+    description = factory.fuzzy.FuzzyText()
+    site = factory.faker.Faker('url')
+    product_code = factory.Sequence(lambda x: f'product_{x}')
+
+    class Meta:
+        model = models.Product

main/tests/test_models.py

@@ -0,0 +1,11 @@
+from django.test import TestCase
+
+from main.models import Product
+from main.tests.factories import ProductFactory
+
+
+class TestModels(TestCase):
+    def test_product_manager(self):
+        ProductFactory.create_batch(2, active=True)
+        ProductFactory.create(active=False)
+        self.assertEqual(2, len(Product.objects.active()))

main/tests/test_signals.py

@@ -0,0 +1,22 @@
+from decimal import Decimal
+
+from django.core.files.images import ImageFile
+from django.test import TestCase
+
+from main import models
+from main.tests.factories import ProductFactory
+
+
+class TestSignal(TestCase):
+    def test_thumbnails_are_generated_on_save(self):
+        product = ProductFactory()
+
+        with open('main/fixtures/cat.jpeg', 'rb') as f:
+            image = models.ProductImage(product=product, image=ImageFile(f, name='cat.jpeg'))
+            image.save()
+        image.refresh_from_db()
+        with open('media/product-thumbnails/cat.jpeg', 'rb') as f:
+            expected_content = f.read()
+            assert image.thumbnail.read() == expected_content
+        image.thumbnail.delete(save=False)
+        image.image.delete(save=False)