Report functionalities

api_doc.txt

@@ -1,6 +1,6 @@
 API Descriptions:
 
-This application provides a RESTful API for Drugstoc Inventory Management.
+This application provides a RESTful API for Drugstoc Inventory Management BE Assessment.
 
 Auth Endpoints:
 
@@ -45,3 +45,72 @@ Inventory Products Endpoints:
    - Request Body: nil
    - Response: nil
 
+
+Inventory Orders Endpoints:
+
+1. POST /api/inventory/orders/
+   - Description: Create a new order
+   - Request Body: 
+   {
+    "items": [
+        {
+            "product": "0aa9ea8dce",
+            "quantity": 1
+        }
+    ]
+   }
+
+   - Response: order fields data
+
+2. GET /api/inventory/orders/
+   - Description: List orders
+   - Request Body: nil
+   - Response: list of orders
+
+3. PUT /api/inventory/orders/:id/status/
+   - Description: Update order status by an admin user
+   - Request Body:
+   {
+    "status": "completed"
+   }
+   - Response: order fields data
+
+4. DELETE /api/inventory/orders/:id/
+   - Description: Delete order
+   - Request Body: nil
+   - Response: nil
+
+
+5. GET /api/inventory/orders/:id/
+   - Description: Get order detail
+   - Request Body: nil
+   - Response: order data
+
+
+Inventory Report Endpoints:
+
+1. GET /api/inventory/report/stock/
+   - Description: Get product out of stock
+   - Request Body: nil
+   - Response: 
+   [
+      {
+         "id": "0aa9ea8dce",
+         "name": "Product Name",
+         "quantity": 0,
+         "description": "Product Description",
+         "created_at": "2024-07-02T14:15:28.043625+01:00",
+         "updated_at": "2024-07-02T15:37:00.599740+01:00"
+      }
+   ]
+
+2. GET /api/inventory/report/sales/
+   - Description: Get product order sales by certain period
+   - Request Body: nil
+   - Response: 
+   [
+      {
+         "date": "2024-07-02",
+         "total_sales": 400
+      }
+   ]

inventory/admin.py

@@ -1,10 +1,26 @@
 from django.contrib import admin
-from .models import Product
+from .models import Product, Order, OrderItem
 
 @admin.register(Product)
 class ProductAdmin(admin.ModelAdmin):
     list_display = ('id', 'name', 'price', 'quantity', 'created_at', 'updated_at')
     list_display_links = ['id', 'name']
     list_filter = ('name',)
     search_fields = ('title', 'description')
+    ordering = ('-created_at',)
+
+
+@admin.register(Order)
+class OrderAdmin(admin.ModelAdmin):
+    list_display = ('id', 'owner', 'status', 'created_at', 'updated_at')
+    list_display_links = ['id', 'owner']
+    list_filter = ('owner',)
+    search_fields = ('status', 'owner')
+    ordering = ('-created_at',)
+
+
+@admin.register(OrderItem)
+class OrderItemAdmin(admin.ModelAdmin):
+    list_display = ('id', 'quantity', 'price', 'created_at', 'updated_at')
+    list_display_links = ['id']
     ordering = ('-created_at',)

inventory/migrations/0010_orderitem_price_alter_orderitem_quantity.py

@@ -0,0 +1,23 @@
+# Generated by Django 5.0.6 on 2024-07-02 14:35
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("inventory", "0009_remove_orderitem_price"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="orderitem",
+            name="price",
+            field=models.PositiveIntegerField(default=0),
+        ),
+        migrations.AlterField(
+            model_name="orderitem",
+            name="quantity",
+            field=models.PositiveIntegerField(default=0),
+        ),
+    ]

inventory/models.py

@@ -43,8 +43,8 @@ class Order(BaseModelMixin):
 class OrderItem(BaseModelMixin):
     order = models.ForeignKey(Order, related_name='items', on_delete=models.CASCADE)
     product = models.ForeignKey(Product, on_delete=models.CASCADE)
-    quantity = models.PositiveIntegerField(default=1)
-    # price = models.PositiveIntegerField(default=1)
+    quantity = models.PositiveIntegerField(default=0)
+    price = models.PositiveIntegerField(default=0)
 
 
     def __str__(self):

inventory/serializers.py

@@ -26,7 +26,7 @@ class OrderItemSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = OrderItem
-        fields = ['id', 'product', 'quantity']
+        fields = ['id', 'product', 'quantity', 'price']
 
 
 class OrderSerializer(serializers.ModelSerializer):
@@ -76,7 +76,17 @@ def process_order_items(self, order, items_data):
             item_price = order_quantity * unit_price
             total_order_price += item_price
 
-            OrderItem.objects.create(order=order, product=product_obj, quantity=order_quantity)
+            OrderItem.objects.create(order=order, product=product_obj, quantity=order_quantity, price=total_order_price)
 
             product_obj.quantity -= order_quantity
-            product_obj.save()
+            product_obj.save()
+
+
+class LowStockProductSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = Product
+        fields = ['id', 'name', 'quantity', 'description', 'created_at', 'updated_at']
+
+class SalesReportSerializer(serializers.Serializer):
+    date = serializers.DateField()
+    total_sales = serializers.IntegerField()

inventory/urls.py

@@ -1,7 +1,8 @@
 # urls.py
 from django.urls import path
 from .views import (InventoryProductList, InventoryProductCreate,
-     InventoryProductDetail,OrderListCreate, OrderDetail, OrderStatusUpdate)
+     InventoryProductDetail,OrderListCreate, OrderDetail, OrderStatusUpdate,
+     LowStockReportView, SalesReportView)
 
 app_name = 'inventory'
 
@@ -12,4 +13,6 @@
     path('orders/', OrderListCreate.as_view(), name='order_list_create'),
     path('orders/<str:pk>/', OrderDetail.as_view(), name='order_detail'),
     path('orders/<str:pk>/status/', OrderStatusUpdate.as_view(), name='order_status_update'),
+    path('report/stock/', LowStockReportView.as_view(), name='low-stock-report'),
+    path('report/sales/<str:period>/', SalesReportView.as_view(), name='sales-report')
 ]

inventory/views.py

@@ -5,9 +5,11 @@
 from rest_framework.views import APIView
 from django.shortcuts import get_object_or_404
 from django.http import Http404
-from .models import Product, Order
+from django.db.models import Sum, F
+from datetime import datetime, timedelta
+from .models import Product, Order, OrderItem
 from users.permissions import IsAdminOrReadOnly
-from .serializers import ProductSerializer, OrderSerializer
+from .serializers import ProductSerializer, OrderSerializer, LowStockProductSerializer, SalesReportSerializer
 from django.db import transaction
 from users.authentication import CustomJWTAuthentication
 
@@ -171,3 +173,45 @@ def update_order_status(self, order, status):
         except Exception as e:
             logger.error(f"Failed to update status for order {order.id}: {str(e)}")
             return None
+
+
+class LowStockReportView(APIView):
+    """
+        Should be accessed by an admin but GET is part of SAFE METHODS for all
+    """
+    permission_classes = [permissions.IsAuthenticated, IsAdminOrReadOnly]
+    authentication_classes = [CustomJWTAuthentication]
+    def get(self, request):
+        low_stock_products = Product.objects.filter(quantity__lt=10)
+        serializer = LowStockProductSerializer(low_stock_products, many=True)
+        return Response(serializer.data)
+
+class SalesReportView(APIView):
+    """
+        Should be accessed by an admin but GET is part of SAFE METHODS for all
+    """
+    permission_classes = [permissions.IsAuthenticated, IsAdminOrReadOnly]
+    authentication_classes = [CustomJWTAuthentication]
+    def get(self, request, period='day'):
+        now = datetime.now()
+
+        match period:
+            case 'day':
+                start_date = now - timedelta(days=1)
+            case  'week':
+                start_date = now - timedelta(weeks=1)
+            case 'month':
+                start_date = now - timedelta(days=30)
+            case _:
+                return Response({'error': 'Invalid period specified.'}, status=status.HTTP_400_BAD_REQUEST)
+
+        sales_data = OrderItem.objects.filter(
+            order__created_at__gte=start_date
+        ).values(
+            date=F('order__created_at__date')
+        ).annotate(
+            total_sales=Sum(F('quantity') * F('price'))
+        )
+
+        serializer = SalesReportSerializer(sales_data, many=True)
+        return Response(serializer.data)