feat: implement backend API clients for multi-marketplace integration and frontend service layer

backend/mm_api/__init__.py

@@ -0,0 +1,15 @@
+from .client import MMClient
+from .services.orders import OrdersService
+from .services.shipments import ShipmentsService
+
+class MagnitMarketAPI:
+    """
+    Main entry point for Magnit Market SDK.
+    Instantiates all services with a shared client.
+    """
+    def __init__(self, api_key: str = None):
+        self.client = MMClient(api_key)
+        
+        # Initialize services
+        self.orders = OrdersService(self.client)
+        self.shipments = ShipmentsService(self.client)

backend/mm_api/client.py

@@ -0,0 +1,67 @@
+import os
+import requests
+import time
+from typing import Dict, Any, Optional
+from .exceptions import MMAPIError, MMAuthError, MMRateLimitError, MMBadRequestError, MMNotFoundError
+
+class MMClient:
+    """Base client for interacting with Magnit Market API."""
+    
+    BASE_URL = "https://b2b-api.magnit.ru"
+    
+    def __init__(self, api_key: Optional[str] = None):
+        # Fetch from env if not provided
+        self.api_key = api_key or os.getenv('MM_API_KEY')
+        
+        if not self.api_key:
+            raise ValueError("MM_API_KEY must be provided")
+            
+        self.session = requests.Session()
+        self.session.headers.update({
+            "X-Api-Key": self.api_key,
+            "Content-Type": "application/json"
+        })
+
+    def request(self, method: str, path: str, data: Optional[Dict[str, Any]] = None, params: Optional[Dict[str, Any]] = None, retries: int = 3) -> Dict[str, Any]:
+        """Perform HTTP request to MM API with automatic retries."""
+        url = f"{self.BASE_URL}{path}"
+        
+        for attempt in range(retries):
+            try:
+                response = self.session.request(method, url, json=data, params=params)
+                
+                # Check rate limiting
+                if response.status_code == 429:
+                    if attempt < retries - 1:
+                        time.sleep(2 ** attempt)  # Exponential backoff
+                        continue
+                    raise MMRateLimitError("Rate limit exceeded")
+
+                if response.status_code in (401, 403):
+                    raise MMAuthError(f"Authentication failed: {response.text}")
+                    
+                if response.status_code == 400:
+                    raise MMBadRequestError(f"Bad Request: {response.text}")
+
+                if response.status_code == 404:
+                    raise MMNotFoundError(f"Not Found: {response.text}")
+                    
+                response.raise_for_status()
+                
+                if response.content:
+                    return response.json()
+                return {}
+
+            except requests.exceptions.RequestException as e:
+                if attempt < retries - 1:
+                    time.sleep(2 ** attempt)
+                    continue
+                raise MMAPIError(f"Request failed: {str(e)}")
+                
+        raise MMAPIError("Request failed after max retries")
+
+    def post(self, path: str, data: Optional[Dict[str, Any]] = None) -> Dict[str, Any]:
+        return self.request("POST", path, data=data)
+
+    def get(self, path: str, params: Optional[Dict[str, Any]] = None) -> Dict[str, Any]:
+        return self.request("GET", path, params=params)

backend/mm_api/exceptions.py

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+class MMAPIError(Exception):
+    """Base exception for all Magnit Market API errors."""
+    pass
+
+class MMAuthError(MMAPIError):
+    """Raised when authentication fails (HTTP 401 or 403)."""
+    pass
+
+class MMRateLimitError(MMAPIError):
+    """Raised when API rate limits are exceeded (HTTP 429)."""
+    pass
+
+class MMBadRequestError(MMAPIError):
+    """Raised when API returns HTTP 400 (Bad Request)."""
+    pass
+
+class MMNotFoundError(MMAPIError):
+    """Raised when API returns HTTP 404 (Not Found)."""
+    pass

backend/mm_api/services/orders.py

@@ -0,0 +1,52 @@
+from typing import Dict, Any, List
+from ..client import MMClient
+
+class OrdersService:
+    """Service to handle Magnit Market Orders (FBS)."""
+    
+    def __init__(self, client: MMClient):
+        self.client = client
+
+    def get_unprocessed_list(self, dir: str = "ASC", page_size: int = 100, page_token: str = None, **filters) -> Dict[str, Any]:
+        """
+        Get list of unprocessed assembly tasks.
+        Endpoint: /api/seller/v1/orders/list/unprocessed
+        """
+        payload = {
+            "dir": dir,
+            "page_size": page_size
+        }
+        if page_token:
+            payload["page_token"] = page_token
+            
+        # Add any extra filters like created_at, cutoff_time, etc.
+        payload.update(filters)
+        
+        return self.client.post("/api/seller/v1/orders/list/unprocessed", data=payload)
+
+    def get_list(self, dir: str = "ASC", page_size: int = 100, page_token: str = None, **filters) -> Dict[str, Any]:
+        """
+        Get list of orders by parameters.
+        Endpoint: /api/seller/v1/orders/list
+        """
+        payload = {
+            "dir": dir,
+            "page_size": page_size
+        }
+        if page_token:
+            payload["page_token"] = page_token
+            
+        payload.update(filters)
+        
+        return self.client.post("/api/seller/v1/orders/list", data=payload)
+
+    def cancel_items(self, order_id: str, items: List[Dict[str, int]]) -> Dict[str, Any]:
+        """
+        Cancel specific items in an order.
+        Endpoint: /api/seller/v1/orders/cancel-items
+        """
+        payload = {
+            "order_id": order_id,
+            "items": items
+        }
+        return self.client.post("/api/seller/v1/orders/cancel-items", data=payload)

backend/mm_api/services/shipments.py

@@ -0,0 +1,30 @@
+from typing import Dict, Any
+from ..client import MMClient
+
+class ShipmentsService:
+    """Service to handle Magnit Market Shipments."""
+    
+    def __init__(self, client: MMClient):
+        self.client = client
+
+    def get_list(self, dir: str = "ASC", page_size: int = 100, page_token: str = None, **filters) -> Dict[str, Any]:
+        """
+        Get list of shipments.
+        Endpoint: /api/seller/v1/shipments/list
+        """
+        payload = {
+            "dir": dir,
+            "page_size": page_size
+        }
+        if page_token:
+            payload["page_token"] = page_token
+            
+        payload.update(filters)
+        return self.client.post("/api/seller/v1/shipments/list", data=payload)
+
+    def confirm(self, shipment_id: str) -> Dict[str, Any]:
+        """
+        Confirm a shipment.
+        Endpoint: /api/seller/v1/shipments/confirm
+        """
+        return self.client.post("/api/seller/v1/shipments/confirm", data={"shipment_id": shipment_id})