feat: add serializers, SKU generator, and views for seller central API

api/serializers.py

@@ -398,8 +398,16 @@ class ProductSerializer(serializers.ModelSerializer):
 
     def validate_sku(self, value):
         clean_sku = str(value or '').strip().upper()
-        if not clean_sku or not re.match(r'^[A-Z0-9][A-Z0-9\-]{1,99}$', clean_sku):
-            clean_sku = f"TRDX-{secrets.token_hex(3).upper()}"
+        clean_sku = re.sub(r'[\s_]+', '-', clean_sku)
+        clean_sku = re.sub(r'[^A-Z0-9\-]', '', clean_sku)
+
+        request = self.context.get('request')
+        user = getattr(request, 'user', None)
+
+        if not clean_sku or (clean_sku.startswith('TRDX-') and len(clean_sku.split('-')) <= 2):
+            from .sku_generator import generate_product_sku
+            category_name = self.initial_data.get('category') if hasattr(self, 'initial_data') else None
+            clean_sku = generate_product_sku(user, category_name)
 
         instance = getattr(self, 'instance', None)
         qs = Product.objects.filter(sku=clean_sku)
@@ -408,23 +416,22 @@ class ProductSerializer(serializers.ModelSerializer):
         
         if qs.exists():
             counter = 1
-            unique_sku = f"{clean_sku}-{counter}"
+            unique_sku = f"{clean_sku}-{counter:02d}"
             while Product.objects.filter(sku=unique_sku).exclude(pk=instance.pk if instance else None).exists():
                 counter += 1
-                unique_sku = f"{clean_sku}-{counter}"
+                unique_sku = f"{clean_sku}-{counter:02d}"
             clean_sku = unique_sku
 
         return clean_sku
 
     def validate_category(self, value):
-        allowed = [
-            "Apparel", "Home Decor", "Sculptures", "Kitchenware", "Jewellery", "Textiles", "Other",
-            "Handicrafts & Art", "Handloom & Textiles", "Home & Living", "Food & Organic",
-            "Beauty & Herbs", "Toys & Folk Art", "Other Craft", "Pottery & Ceramics",
-            "Brass & Metal Craft", "Woodcraft & Carvings"
-        ]
+        from .sku_generator import CATEGORY_CODES
+        allowed = list(CATEGORY_CODES.keys()) + ["Other"]
         if value not in allowed:
-            return "Other"
+            for cat in allowed:
+                if cat.lower() == str(value).strip().lower():
+                    return cat
+            return value or "Handicrafts & Folk Art"
         return value
 
     def validate(self, attrs):

api/sku_generator.py

@@ -0,0 +1,99 @@
+import re
+import logging
+
+logger = logging.getLogger('api')
+
+CATEGORY_CODES = {
+    'Food & Beverages': 'FNB',
+    'Personal Care': 'PCR',
+    'Hygiene & Reusable Care': 'HYG',
+    'Clothing & Textiles': 'TEX',
+    'Bags, Footwear & Leather': 'LEA',
+    'Jewellery': 'JWL',
+    'Home Decor & Furnishings': 'DEC',
+    'Kitchen & Dining': 'KIT',
+    'Eco Packaging & Disposables': 'PKG',
+    'Handicrafts & Folk Art': 'ART',
+    'Wooden, Bamboo & Coir Products': 'WOD',
+    'Toys & Games': 'TOY',
+    'Baby & Kids': 'KID',
+    'Pet Products': 'PET',
+    'Eco Cleaning Products': 'CLN',
+    'Farm, Garden & Compost': 'GRD',
+    'Stationery, Office & Tech': 'STN',
+    'Engineering & Manufactured Goods': 'ENG',
+    # Legacy categories mapped to official codes
+    'Handicrafts & Art': 'ART',
+    'Handloom & Textiles': 'TEX',
+    'Home & Living': 'DEC',
+    'Food & Organic': 'FNB',
+    'Beauty & Herbs': 'PCR',
+    'Toys & Folk Art': 'TOY',
+    'Pottery & Ceramics': 'ART',
+    'Brass & Metal Craft': 'ART',
+    'Woodcraft & Carvings': 'WOD',
+    'Apparel': 'TEX',
+    'Sculptures': 'ART',
+    'Kitchenware': 'KIT',
+    'Textiles': 'TEX',
+}
+
+def get_category_code(category_name):
+    """
+    Returns the standardized 3-letter uppercase category code.
+    """
+    if not category_name:
+        return 'GEN'
+    clean = str(category_name).strip()
+    if clean in CATEGORY_CODES:
+        return CATEGORY_CODES[clean]
+
+    lower = clean.lower()
+    for cat, code in CATEGORY_CODES.items():
+        if cat.lower() == lower or cat.lower() in lower or lower in cat.lower():
+            return code
+
+    alnum = re.sub(r'[^A-Z0-9]', '', clean.upper())
+    return (alnum[:3] if len(alnum) >= 3 else alnum.ljust(3, 'X'))
+
+def normalize_merchant_id(user):
+    """
+    Extracts and standardizes the seller's Merchant ID (TRDPX000001 format).
+    """
+    if not user:
+        return 'TRDPX000001'
+
+    profile = getattr(user, 'profile', None)
+    mid = getattr(profile, 'merchant_id', None)
+    if not mid:
+        draft = getattr(user, 'onboarding_draft', None)
+        mid = getattr(draft, 'merchant_id', None)
+
+    if mid and str(mid).strip():
+        return str(mid).strip().upper().replace(' ', '')
+
+    user_id = getattr(user, 'id', 1)
+    return f"TRDPX{str(user_id).zfill(6)}"
+
+def generate_product_sku(user, category_name=None, product_model=None):
+    """
+    Generates a unique SKU in format: TRDX-[categorycode]-[sellermid]-[productsno]
+    e.g. TRDX-TEX-TRDPX000042-001
+    """
+    if product_model is None:
+        from .models import Product
+        product_model = Product
+
+    cat_code = get_category_code(category_name)
+    mid = normalize_merchant_id(user)
+
+    user_product_count = product_model.objects.filter(supplier=user).count() if user else 0
+    seq = user_product_count + 1
+
+    candidate_sku = f"TRDX-{cat_code}-{mid}-{seq:03d}"
+    while product_model.objects.filter(sku=candidate_sku).exists():
+        seq += 1
+        candidate_sku = f"TRDX-{cat_code}-{mid}-{seq:03d}"
+
+    logger.info("Generated SKU: %s for user=%s category=%s", candidate_sku, getattr(user, 'username', 'anon'), category_name)
+    return candidate_sku

api/views.py

@@ -1337,7 +1337,10 @@ class BulkUploadView(APIView):
             if not title or not str(title).strip():
                 row_errors.append("Missing Product Title")
             if not sku or not str(sku).strip():
-                row_errors.append("Missing SKU code")
+                from .sku_generator import generate_product_sku
+                sku = generate_product_sku(user, category_val)
+            else:
+                sku = str(sku).strip().upper()
             if price_val <= 0:
                 row_errors.append("Invalid Price (must be a positive number > 0)")
             if stock_val < 0: