organize interface_adapters. add cart_controller

src/interface_adapters/controllers/cart_controller.py

@@ -0,0 +1,32 @@
+#python imports
+from fastapi import APIRouter, HTTPException
+from fastapi.responses import JSONResponse
+
+#dependency imports
+from use_cases.view_cart import ViewCart
+from interface_adapters.dtos.view_cart_response import ViewCartResponseDTO, CartItemDTO
+from interface_adapters.dtos.view_cart_request import ViewCartRequestDTO
+from interface_adapters.repositories.cart_repository import CartRepository
+from interface_adapters.mocks.cart_db import CartDatabase
+
+# Initialize components
+cart_database = CartDatabase()  # Concrete database implementation
+cart_repository = CartRepository(cart_database)  # Repository depends on gateway
+view_cart_use_case = ViewCart(cart_repository)  # Use case depends on repository
+
+router = APIRouter()
+
+@router.post("/view_cart", response_model=ViewCartResponseDTO)
+async def view_cart(request_dto: ViewCartRequestDTO):
+
+    cart = view_cart_use_case.execute(request_dto.user_id)
+
+    if not cart:
+        raise HTTPException(status_code=404, detail="Cart not found")
+
+    response_dto = ViewCartResponseDTO(
+        items=[CartItemDTO(product_id=item.product_id, quantity=item.quantity, price=item.price) for item in cart.items],
+        total_price=sum(item.price * item.quantity for item in cart.items)
+    )
+    
+    return response_dto

src/interface_adapters/dtos/view_cart_request.py

@@ -0,0 +1,6 @@
+#python imports
+from pydantic import BaseModel
+from typing import List, Optional
+
+class ViewCartRequestDTO(BaseModel):
+    user_id: int

src/interface_adapters/dtos/view_cart_response.py

@@ -0,0 +1,12 @@
+#python imports
+from pydantic import BaseModel
+from typing import List, Optional
+
+class CartItemDTO(BaseModel):
+    product_id: int
+    quantity: int
+    price: float
+
+class ViewCartResponseDTO(BaseModel):
+    items: List[CartItemDTO] = []
+    total_price: float = 0.0

src/interface_adapters/mocks/cart_db.py

@@ -0,0 +1,21 @@
+#python imports
+from typing import Optional, List
+
+#dependency imports
+from interface_adapters.repositories.cart_database_interface import CartDatabaseInterface
+
+class CartDatabase(CartDatabaseInterface):
+    def __init__(self):
+        # Mock database setup
+        self.mock_db = {
+            1: [
+                {"product_id": 101, "name": "Apple", "quantity": 2, "price": 0.5},
+                {"product_id": 102, "name": "Milk", "quantity": 1, "price": 1.5},
+            ],
+            2: [
+                {"product_id": 201, "name": "Bread", "quantity": 1, "price": 2.0},
+            ],
+        }
+
+    def fetch_cart_items(self, user_id: int) -> Optional[List[dict]]:
+        return self.mock_db.get(user_id)

src/interface_adapters/repositories/cart_database_interface.py

@@ -1,3 +1,4 @@
+#python imports
 from typing import Optional, List
 
 class CartDatabaseInterface:

src/interface_adapters/repositories/cart_repository.py

@@ -3,7 +3,7 @@ from typing import Optional, List
 
 #dependency imports
 from use_cases.cart_repository_interface import CartRepositoryInterface
-from interface_adapters.cart_database_interface import CartDatabaseInterface
+from interface_adapters.repositories.cart_database_interface import CartDatabaseInterface
 
 class CartRepository(CartRepositoryInterface):
     def __init__(self, database_gateway: CartDatabaseInterface):

src/main.py

@@ -0,0 +1,11 @@
+from interface_adapters.controllers.cart_controller import router as cart_router
+
+from fastapi import FastAPI
+
+app = FastAPI()
+app.include_router(cart_router)
+
+@app.get("/")
+async def root():
+    return {"message": "Hello World"}
+