{"id":167,"date":"2025-10-28T02:25:53","date_gmt":"2025-10-28T02:25:53","guid":{"rendered":"https:\/\/codetypingpro.com\/?p=167"},"modified":"2025-12-17T07:45:30","modified_gmt":"2025-12-17T07:45:30","slug":"26-real-world-python-projects-simple-e-commerce-backend","status":"publish","type":"post","link":"https:\/\/codetypingpro.com\/?p=167","title":{"rendered":"26 – Real-World Python Projects – Simple E-commerce Backend"},"content":{"rendered":"\n

\ud83c\udfaf Project<\/strong> Objective<\/strong><\/h3>\n\n\n\n

To design a Python program that handles products, users, carts, and orders<\/strong> \u2014 the essential logic behind an e-commerce website (no front-end required).<\/p>\n\n\n\n

\n\n\n\n

\ud83e\udde9 1. Overview<\/strong><\/h2>\n\n\n\n

You\u2019ll build a console-based backend<\/strong> that supports:<\/p>\n\n\n\n

    \n
  • \u2705 User registration\/login<\/li>\n\n\n\n
  • \ud83d\udecd\ufe0f Product catalog management<\/li>\n\n\n\n
  • \ud83d\uded2 Cart and checkout system<\/li>\n\n\n\n
  • \ud83d\udcb3 Order tracking<\/li>\n<\/ul>\n\n\n\n

    We\u2019ll simulate database operations using JSON files<\/strong>, but it can easily upgrade to SQLite or MySQL<\/strong> later.<\/p>\n\n\n\n

    \n\n\n\n

    \u2699\ufe0f 2. Setup<\/strong><\/h2>\n\n\n\n

    We\u2019ll use:<\/p>\n\n\n\n

    Library<\/th>Purpose<\/th><\/tr><\/thead>
    json<\/code><\/td>Store and read database files<\/td><\/tr>
    uuid<\/code><\/td>Generate unique IDs for products\/orders<\/td><\/tr>
    datetime<\/code><\/td>Timestamp orders<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

    No external installation needed \u2014 all built-in!<\/p>\n\n\n\n

    \n\n\n\n

    \ud83e\uddf1 3. File Structure<\/strong><\/h2>\n\n\n\n
    ecommerce_backend\/\n\u2502\n\u251c\u2500\u2500 main.py\n\u251c\u2500\u2500 users.json\n\u251c\u2500\u2500 products.json\n\u2514\u2500\u2500 orders.json\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83d\udce6 4. Starter Code<\/strong><\/h2>\n\n\n\n
    main.py<\/strong><\/h3>\n\n\n\n
    import json, uuid, datetime, os\n\n# ---------- DATABASE HANDLERS ----------\ndef load_data(filename):\n    if not os.path.exists(filename):\n        return []\n    with open(filename, \"r\") as f:\n        return json.load(f)\n\ndef save_data(filename, data):\n    with open(filename, \"w\") as f:\n        json.dump(data, f, indent=4)\n\n# ---------- USER SYSTEM ----------\ndef register_user():\n    users = load_data(\"users.json\")\n    name = input(\"Enter your name: \")\n    email = input(\"Enter your email: \")\n    password = input(\"Enter password: \")\n\n    for u in users:\n        if u[\"email\"] == email:\n            print(\"\u274c Email already registered.\")\n            return\n\n    user = {\n        \"id\": str(uuid.uuid4()),\n        \"name\": name,\n        \"email\": email,\n        \"password\": password\n    }\n    users.append(user)\n    save_data(\"users.json\", users)\n    print(\"\u2705 Registration successful!\")\n\ndef login_user():\n    users = load_data(\"users.json\")\n    email = input(\"Email: \")\n    password = input(\"Password: \")\n\n    for u in users:\n        if u[\"email\"] == email and u[\"password\"] == password:\n            print(f\"\u2705 Welcome {u['name']}!\")\n            return u\n    print(\"\u274c Invalid credentials.\")\n    return None\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83d\udecd\ufe0f 5. Product Management<\/strong><\/h2>\n\n\n\n
    def add_product():\n    products = load_data(\"products.json\")\n    name = input(\"Product name: \")\n    price = float(input(\"Price: \"))\n    stock = int(input(\"Stock quantity: \"))\n\n    product = {\n        \"id\": str(uuid.uuid4()),\n        \"name\": name,\n        \"price\": price,\n        \"stock\": stock\n    }\n    products.append(product)\n    save_data(\"products.json\", products)\n    print(\"\u2705 Product added successfully!\")\n\ndef list_products():\n    products = load_data(\"products.json\")\n    if not products:\n        print(\"No products available.\")\n        return\n    print(\"\\n\ud83d\uded2 Product List:\")\n    for p in products:\n        print(f\"ID: {p['id'][:6]} | {p['name']} - \u20b9{p['price']} (Stock: {p['stock']})\")\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83d\uded2 6. Cart & Checkout<\/strong><\/h2>\n\n\n\n
    cart = []\n\ndef add_to_cart():\n    products = load_data(\"products.json\")\n    list_products()\n    pid = input(\"Enter product ID to add to cart: \")\n    for p in products:\n        if p[\"id\"].startswith(pid):\n            qty = int(input(\"Enter quantity: \"))\n            if qty <= p[\"stock\"]:\n                cart.append({\"product\": p, \"qty\": qty})\n                print(f\"\u2705 Added {qty} x {p['name']} to cart\")\n                return\n            else:\n                print(\"\u274c Not enough stock.\")\n                return\n    print(\"\u274c Product not found.\")\n\ndef view_cart():\n    if not cart:\n        print(\"\ud83d\uded2 Cart is empty.\")\n        return\n    print(\"\\n\ud83e\uddfe Your Cart:\")\n    total = 0\n    for item in cart:\n        subtotal = item[\"product\"][\"price\"] * item[\"qty\"]\n        total += subtotal\n        print(f\"{item['product']['name']} \u00d7 {item['qty']} = \u20b9{subtotal}\")\n    print(f\"\\nTotal: \u20b9{total}\")\n\ndef checkout(user):\n    if not cart:\n        print(\"Cart empty.\")\n        return\n    products = load_data(\"products.json\")\n    orders = load_data(\"orders.json\")\n\n    total = sum(item[\"product\"][\"price\"] * item[\"qty\"] for item in cart)\n    order = {\n        \"id\": str(uuid.uuid4()),\n        \"user_id\": user[\"id\"],\n        \"items\": [{\"name\": i[\"product\"][\"name\"], \"qty\": i[\"qty\"]} for i in cart],\n        \"total\": total,\n        \"date\": datetime.datetime.now().strftime(\"%Y-%m-%d %H:%M\")\n    }\n\n    # Update stock\n    for item in cart:\n        for p in products:\n            if p[\"id\"] == item[\"product\"][\"id\"]:\n                p[\"stock\"] -= item[\"qty\"]\n\n    save_data(\"products.json\", products)\n    orders.append(order)\n    save_data(\"orders.json\", orders)\n    cart.clear()\n\n    print(f\"\u2705 Order placed! Total amount: \u20b9{total}\")\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83e\udded 7. Main Menu<\/strong><\/h2>\n\n\n\n
    def main():\n    print(\"=== \ud83d\uded2 Simple E-commerce Backend ===\")\n    user = None\n\n    while True:\n        print(\"\\n1. Register\")\n        print(\"2. Login\")\n        print(\"3. Add Product (Admin)\")\n        print(\"4. List Products\")\n        print(\"5. Add to Cart\")\n        print(\"6. View Cart\")\n        print(\"7. Checkout\")\n        print(\"8. Exit\")\n\n        choice = input(\"Choose an option: \")\n\n        if choice == \"1\":\n            register_user()\n        elif choice == \"2\":\n            user = login_user()\n        elif choice == \"3\":\n            add_product()\n        elif choice == \"4\":\n            list_products()\n        elif choice == \"5\":\n            if user: add_to_cart()\n            else: print(\"\ud83d\udd12 Please log in first.\")\n        elif choice == \"6\":\n            view_cart()\n        elif choice == \"7\":\n            if user: checkout(user)\n            else: print(\"\ud83d\udd12 Please log in first.\")\n        elif choice == \"8\":\n            print(\"\ud83d\udc4b Exiting...\")\n            break\n        else:\n            print(\"\u274c Invalid choice.\")\n<\/code><\/pre>\n\n\n\n
    if __name__ == \"__main__\":\n    main()\n<\/code><\/pre>\n\n\n\n
    \n\n\n\n
    \ud83e\udde0 8. How It Works<\/strong><\/h2>\n\n\n\n
    Component<\/th>Description<\/th><\/tr><\/thead>
    users.json<\/code><\/td>Stores users and credentials<\/td><\/tr>
    products.json<\/code><\/td>Holds product catalog<\/td><\/tr>
    orders.json<\/code><\/td>Tracks completed orders<\/td><\/tr>
    cart<\/code><\/td>Temporary session cart in memory<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    \n\n\n\n
    \ud83d\udca1 9. Enhancement Ideas<\/strong><\/h2>\n\n\n\n
    Feature<\/th>Description<\/th><\/tr><\/thead>
    \ud83d\udcb3 Payment Simulation<\/td>Simulate payments via wallet or mock API<\/td><\/tr>
    \ud83d\udce6 Shipping Status<\/td>Add delivery tracking & updates<\/td><\/tr>
    \ud83d\udc64 Admin Panel<\/td>Differentiate between customers & admins<\/td><\/tr>
    \ud83e\uddfe Invoice<\/td>Generate PDF invoice using reportlab<\/code><\/td><\/tr>
    \ud83d\uddc4\ufe0f Database<\/td>Use SQLite instead of JSON for real persistence<\/td><\/tr>
    \ud83c\udf10 Flask API<\/td>Expose endpoints for a front-end app or mobile app<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    \n\n\n\n
    \u2705 Summary<\/strong><\/h2>\n\n\n\n
    Module<\/th>Purpose<\/th><\/tr><\/thead>
    \ud83e\uddcd User System<\/td>Register, Login<\/td><\/tr>
    \ud83d\udecd\ufe0f Product Management<\/td>Add & list products<\/td><\/tr>
    \ud83d\uded2 Cart System<\/td>Add, view, checkout<\/td><\/tr>
    \ud83d\udcbe Persistence<\/td>JSON-based data storage<\/td><\/tr>
    \ud83d\udca1 Extendable<\/td>Can upgrade to full web backend<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
    <\/p>\n","protected":false},"excerpt":{"rendered":"
    \ud83c\udfaf Project Objective To design a Python program that handles products, users, carts, and orders \u2014 the essential logic behind an e-commerce website (no front-end required). \ud83e\udde9 1. Overview You\u2019ll build a console-based backend that supports: We\u2019ll simulate database operations using JSON files, but it can easily upgrade to SQLite or MySQL later. \u2699\ufe0f 2. […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-167","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts\/167","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=167"}],"version-history":[{"count":2,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts\/167\/revisions"}],"predecessor-version":[{"id":305,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=\/wp\/v2\/posts\/167\/revisions\/305"}],"wp:attachment":[{"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=167"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=167"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/codetypingpro.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=167"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}