Refactor the way it stores the prices

The exact same product might have slightly different names in different stores.
So we need to make a more complex relation

Product -> ProductNameLocation -> ProductPrice

products/admin.py

@@ -1,16 +1,30 @@
 from django.contrib import admin
-from .models import Product, ProductCategory, ProductBrand
+from .models import Product, ProductCategory, ProductBrand, ProductNameLocation, ProductPrice, Location
 
 
 class ProductAdmin(admin.ModelAdmin):
-    list_display = ["name", "brand", "category"]
+    list_display = ["generic_name", "brand", "category"]
 
 class ProductCategoryAdmin(admin.ModelAdmin):
     list_display = ["name", "description"]
 
 class ProductBrandAdmin(admin.ModelAdmin):
     list_display = ["name", "description"]
 
+class ProductNameLocationAdmin(admin.ModelAdmin):
+    list_display = ["product", "location", "name"]
+
+class ProductPriceAdmin(admin.ModelAdmin):
+    list_display = ["product", "timestamp", "price"]
+
+class LocationAdmin(admin.ModelAdmin):
+    list_display = ["name", "base_url", "get_product_url"]
+
+
 admin.site.register(Product, ProductAdmin)
 admin.site.register(ProductCategory, ProductCategoryAdmin)
 admin.site.register(ProductBrand, ProductBrandAdmin)
+admin.site.register(ProductNameLocation, ProductNameLocationAdmin)
+admin.site.register(ProductPrice, ProductPriceAdmin)
+admin.site.register(Location, LocationAdmin)
+

products/migrations/0001_initial.py

@@ -1,4 +1,4 @@
-# Generated by Django 5.0 on 2023-12-16 22:55
+# Generated by Django 5.0 on 2023-12-17 18:01
 
 import django.db.models.deletion
 from django.db import migrations, models
@@ -12,6 +12,15 @@ class Migration(migrations.Migration):
     ]
 
     operations = [
+        migrations.CreateModel(
+            name='Location',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=200)),
+                ('base_url', models.CharField(blank=True, max_length=200)),
+                ('get_product_url', models.CharField(blank=True, max_length=200)),
+            ],
+        ),
         migrations.CreateModel(
             name='ProductBrand',
             fields=[
@@ -32,20 +41,29 @@ class Migration(migrations.Migration):
             name='Product',
             fields=[
                 ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('name', models.CharField(max_length=200)),
+                ('code', models.CharField(max_length=10)),
+                ('generic_name', models.CharField(max_length=200)),
                 ('description', models.TextField()),
                 ('brand', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='products', to='products.productbrand')),
                 ('category', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='products', to='products.productcategory')),
             ],
         ),
+        migrations.CreateModel(
+            name='ProductNameLocation',
+            fields=[
+                ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=200)),
+                ('location', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='product_names', to='products.location')),
+                ('product', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='product_name_at_locations', to='products.product')),
+            ],
+        ),
         migrations.CreateModel(
             name='ProductPrice',
             fields=[
                 ('id', models.BigAutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
                 ('timestamp', models.DateTimeField(auto_now_add=True)),
-                ('location', models.CharField(max_length=200)),
                 ('price', models.DecimalField(decimal_places=2, max_digits=6)),
-                ('product', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='prices', to='products.product')),
+                ('product', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='prices', to='products.productnamelocation')),
             ],
             options={
                 'ordering': ('-timestamp',),

products/models.py

@@ -20,60 +20,108 @@ def __str__(self):
         return self.name
 
 
-class Product(models.Model):
+class Location(models.Model):
     name = models.CharField(max_length=200)
+    base_url = models.CharField(max_length=200, blank=True)
+    get_product_url = models.CharField(max_length=200, blank=True)
+
+    def __str__(self):
+        return self.name
+
+class Product(models.Model):
+    code = models.CharField(max_length=10)
+    generic_name = models.CharField(max_length=200)
     description = models.TextField()
     category = models.ForeignKey(ProductCategory, on_delete=models.CASCADE, related_name="products")
     brand = models.ForeignKey(ProductBrand, on_delete=models.CASCADE, related_name="products")
 
     def __str__(self):
-        return self.name
+        return f"{self.generic_name} ({self.brand.name})"
 
-    @property
-    def latest_max_price(self):
-        latest_prices = self.get_latest_prices()
+    # @property
+    # def latest_max_price(self):
+    #     latest_prices = self.get_latest_prices()
 
-        # Get the maximum value of the latest prices
-        max_latest_price = latest_prices.aggregate(Max('latest_price', output_field=DecimalField()))['latest_price__max']
+    #     # Get the maximum value of the latest prices
+    #     max_latest_price = latest_prices.aggregate(Max('latest_price', output_field=DecimalField()))['latest_price__max']
 
-        return max_latest_price
+    #     return max_latest_price
 
-    @property
-    def latest_min_price(self):
-        latest_prices = self.get_latest_prices()
+    # @property
+    # def latest_min_price(self):
+    #     latest_prices = self.get_latest_prices()
 
-        # Get the maximum value of the latest prices
-        min_latest_price = latest_prices.aggregate(Min('latest_price', output_field=DecimalField()))['latest_price__min']
+    #     # Get the maximum value of the latest prices
+    #     min_latest_price = latest_prices.aggregate(Min('latest_price', output_field=DecimalField()))['latest_price__min']
 
-        return min_latest_price
+    #     return min_latest_price
 
-    def get_latest_prices(self):
-        """Get most recent prices for each location"""
+    # def get_latest_prices(self):
+    #     """Get most recent prices for each location"""
+
+    #     # Query to get distinct locations from ProductPrice model
+    #     # distinct_locations = ProductPrice.objects.values('location').distinct()
+    #     distinct_locations = ProductPrice.objects.all()
 
-        # Query to get distinct locations from ProductPrice model
-        distinct_locations = ProductPrice.objects.values('location').distinct()
+    #     # Subquery to get the latest timestamp for each location
+    #     latest_timestamp_subquery = ProductPrice.objects.filter(
+    #         location=OuterRef('location')
+    #     ).order_by('-timestamp').values('timestamp')[:1]
 
+    #     # Query to get the latest price for each location
+    #     latest_prices = ProductPrice.objects.filter(
+    #         location__in=Subquery(distinct_locations.values('location')),
+    #         timestamp=Subquery(latest_timestamp_subquery)
+    #     ).annotate(
+    #         latest_price=Coalesce('price', 0)
+    #     ).values('location', 'latest_price')
+
+    #     return latest_prices
+
+    def get_latest_prices(self):
         # Subquery to get the latest timestamp for each location
         latest_timestamp_subquery = ProductPrice.objects.filter(
-            location=OuterRef('location')
+            product__product=self
         ).order_by('-timestamp').values('timestamp')[:1]
 
         # Query to get the latest price for each location
         latest_prices = ProductPrice.objects.filter(
-            location__in=Subquery(distinct_locations.values('location')),
+            product__product=self,
             timestamp=Subquery(latest_timestamp_subquery)
         ).annotate(
-            latest_price=Coalesce('price', 0)
-        ).values('location', 'latest_price')
+            latest_price=Coalesce('price', 0),
+            location_name=OuterRef('product__location__name')
+        ).values('location_name', 'latest_price')
 
         return latest_prices
+
+    def get_max_latest_price(self):
+        # Get the maximum value of the latest prices
+        max_latest_price = self.get_latest_prices().aggregate(Max('latest_price', output_field=DecimalField()))['latest_price__max']
+        return max_latest_price
+
+    def get_min_latest_price(self):
+        # Get the minimum value of the latest prices
+        min_latest_price = self.get_latest_prices().aggregate(Min('latest_price', output_field=DecimalField()))['latest_price__min']
+        return min_latest_price
 
+class ProductNameLocation(models.Model):
+    """Save different names at different stores for the same product"""
+    product = models.ForeignKey(Product, on_delete=models.CASCADE, related_name="product_name_at_locations")
+    location = models.ForeignKey(Location, on_delete=models.CASCADE, related_name="product_names")
+    name = models.CharField(max_length=200)
+
+    def __str__(self):
+        return f"{self.name} ({self.product.brand}) at {self.location}"
 
 class ProductPrice(models.Model):
-    product = models.ForeignKey(Product, on_delete=models.CASCADE, related_name='prices')
+    product = models.ForeignKey(ProductNameLocation, on_delete=models.CASCADE, related_name='prices')
     timestamp = models.DateTimeField(auto_now_add=True)
-    location = models.CharField(max_length=200)
+    # location = models.ForeignKey(Location, on_delete=models.CASCADE, related_name="product_prices_at_locations")
     price = models.DecimalField(max_digits=6, decimal_places=2)
 
+    def __str__(self):
+        return f"{self.product.name}: {self.price} at {self.product.location.name}"
+
     class Meta:
         ordering = ("-timestamp",)

products/templates/product_list.html

@@ -15,10 +15,18 @@ <h2>Product List</h2>
         <ul>
             {% for product in products %}
                 <li>
+                    <strong>Code:</strong> {{ product.code }}<br>
                     <strong>Category:</strong> {{ product.category }}<br>
                     <strong>Brand:</strong> {{ product.brand }}<br>
-                    <strong>Name:</strong> {{ product.name }}<br>
-                    <strong>Description:</strong> {{ product.description }}
+                    <strong>Name:</strong> {{ product.generic_name }}<br>
+                    <strong>Description:</strong> {{ product.description }}<br>
+                    <strong>Prices:</strong>
+                    <ul>
+                        <li>TODO: Price 1</li>
+                        <li>TODO: Price 2</li>
+                        <li>TODO: Price 3</li>
+                    </ul>
+
                 </li>
                 <br>
             {% endfor %}

products/tests.py

@@ -1,39 +1,48 @@
 from django.test import TestCase
-from .models import Product, ProductBrand, ProductCategory, ProductPrice
+from .models import Product, ProductBrand, ProductCategory, ProductPrice, ProductNameLocation, Location
 
 
 class ProductTest(TestCase):
     def setUp(self):
         brand = ProductBrand.objects.create(name="Brand1", description="Brand1")
         category = ProductCategory.objects.create(name="Category1", description="Category1")
-        Product.objects.create(name="Product1", brand=brand, category=category)
+        product = Product.objects.create(code="A01", generic_name="Product1", brand=brand, category=category)
+        location_disco = Location.objects.create(name="Disco")
+        location_tata = Location.objects.create(name="Ta-Ta")
 
-    def test_product_is_created(self):
-        product = Product.objects.get(name="Product1")
-        self.assertEqual(product.name, "Product1")
-        self.assertEqual(product.brand.name, "Brand1")
-        self.assertEqual(product.category.name, "Category1")
+        self.product_name_at_disco = ProductNameLocation.objects.create(product=product, location=location_disco, name="Product #1")
+        self.product_name_at_tata = ProductNameLocation.objects.create(product=product, location=location_tata, name="Product Number1")
+
+    # def test_product_is_created(self):
+    #     product = Product.objects.get(generic_name="Product1")
+    #     self.assertEqual(product.generic_name, "Product1")
+    #     self.assertEqual(product.brand.name, "Brand1")
+    #     self.assertEqual(product.category.name, "Category1")
 
     def test_latest_max_and_min_price(self):
-        product = Product.objects.get(name="Product1")
+        product = Product.objects.get(generic_name="Product1")
 
-        price1 = ProductPrice.objects.create(product=product, location="Disco", price=99)
-        price2 = ProductPrice.objects.create(product=product, location="Ta-Ta", price=100)
-        product.prices.add(price1, price2)
+        price1 = ProductPrice.objects.create(product=self.product_name_at_disco, price=99)
+        price2 = ProductPrice.objects.create(product=self.product_name_at_tata, price=100)
+        # self.product_name_at_disco.prices.add(price1)
 
-        price3 = ProductPrice.objects.create(product=product, location="Disco", price=99)
-        price4 = ProductPrice.objects.create(product=product, location="Ta-Ta", price=98)
-        product.prices.add(price3, price4)
+        price4 = ProductPrice.objects.create(product=self.product_name_at_tata, price=98)
+        price3 = ProductPrice.objects.create(product=self.product_name_at_disco, price=99)
+        # product.prices.add(price3, price4)
 
-        price5 = ProductPrice.objects.create(product=product, location="Disco", price=96)
-        price6 = ProductPrice.objects.create(product=product, location="Ta-Ta", price=97)
-        product.prices.add(price5, price6)
+        self.assertEqual(product.get_min_latest_price(), 98)
+        self.assertEqual(product.get_max_latest_price(), 99)
 
-        self.assertEqual(product.latest_min_price, 96)
-        self.assertEqual(product.latest_max_price, 97)
-
-    def test_upload_xlsx(self):
-        # Create a XLSX file
-        # Send a POST Request imitating the form
-        # Validate that all products were created, counting them
-        raise NotImplementedError
+        # price5 = ProductPrice.objects.create(product=self.product_name_at_disco, price=96)
+        # price6 = ProductPrice.objects.create(product=self.product_name_at_tata, price=97)
+        # product.product_name_at_locations.prices.add(price5, price6)
+
+        # self.assertEqual(product.latest_min_price, 96)
+        # self.assertEqual(product.get_min_latest_price(), 96)
+        # self.assertEqual(product.get_max_latest_price(), 97)
+
+    # def test_upload_xlsx(self):
+    #     # Create a XLSX file
+    #     # Send a POST Request imitating the form
+    #     # Validate that all products were created, counting them
+    #     raise NotImplementedError