🔌 Python API Demo – WordPress Plugin (Full OOP Integration)

A fully object-oriented WordPress plugin that connects to an external Python FastAPI backend, fetches product data, displays it using a shortcode, and allows adding new products through the WordPress admin.

This plugin is meant as a clean, well-structured example of integrating WordPress with a remote API using modern coding standards.

📦 Features

✔ Fetch all products (GET /products)

• Displays all available products from the Python API.

✔ Fetch single product by ID (GET /product/{id})

• You can fetch and display one specific product using: [python_product id="10"]

✔ Add new products (POST /product/add)

• Admin-side form allows adding new products to the API.

✔ Shortcodes included

• Display all products: [python_products]
• Limit products: [python_products limit="5"]
• Display a single product: [python_product id="7"]

✔ Admin settings page

• Located at: Settings → Python API Demo
• Allows configuration of:
  • API Base URL
  • API Key
  • Enable/Disable caching
  • Cache duration
  • Add product form (POST request)

✔ Optional caching (WordPress transients)

• Reduces API calls
• Cached for X seconds (configurable)
• Cache automatically clears on new product POST

✔ Full OOP architecture

• The plugin uses a loader class and clean separation of concerns.

📁 Folder Structure

python-api-demo/
├── python-api-demo.php              # Main plugin loader
├── includes/
│   ├── class-plugin-loader.php      # Initializes plugin classes
│   ├── class-api-client.php         # Performs GET/POST requests to Python API
│   ├── class-admin-page.php         # Settings page (API URL, token, caching)
│   ├── class-products-shortcode.php # Shortcode: all products + limit
│   ├── class-product-shortcode.php  # Shortcode: single product by ID
│   ├── class-product-form.php       # Add product via POST to API
│   └── helpers.php                  # Sanitization, utility helpers
├── assets/
│   └── admin.css
└── README.md

🛠 Installation

1. Download the plugin or clone the repository.

2. Upload to your WordPress installation under: wp-content/plugins/

3. Activate the plugin.

4. Open: Settings → Python API Demo

5. Configure:

   • API Base URL (e.g http://127.0.0.1:8000/)
   • API Key
   • Cache settings

6. Add one of the shortcodes to your page/post.

🧩 Shortcodes

1️⃣ Display ALL products

[python_products]

With limit:

[python_products limit="3"]

2️⃣ Display a SINGLE product

[python_product id="10"]

If product does not exist → shows a styled "Product not found" message.

🔗 API Communication

All API requests use:

Headers:

X-API-KEY: YOUR_API_KEY
Content-Type: application/json

📥 GET all products

GET {API_URL}/products

PHP example (inside class-api-client.php):

$response = wp_remote_get(
    trailingslashit( $base_url ) . 'products',
    [ 'headers' => $this->get_headers() ]
);

📥 GET single product

GET {API_URL}/product/{id}

Shortcode example:

[python_product id="5"]

📤 POST add product

Endpoint:

POST {API_URL}/product/add

Sent JSON structure:

{
    "name": "Keyboard Pro",
    "price": 89.99,
    "image": "https://example.com/kb.jpg",
    "stock": 10
}

PHP example:

$response = wp_remote_post(
    trailingslashit( $base_url ) . 'product/add',
    [
        'headers' => $this->get_headers(),
        'body'    => json_encode( $data ),
    ]
);

🧱 Admin Settings Page

Located in: ⚙ Settings → Python API Demo

It contains:

✔ API Base URL

✔ API Key

✔ Caching Options

• enable / disable
• cache lifetime (seconds)

✔ Add New Product Form

Fields:

• Name
• Price
• Image URL
• In Stock (1/0)

The form sends POST request directly to Python API and clears cache.

⚙ Internal Plugin Architecture

class-plugin-loader.php

• Initializes all components in correct order.

class-api-client.php

• Handles communication with Python API:
  • GET all products
  • GET single product
  • POST new product
  • Caching layer
  • Headers & error handling

class-products-shortcode.php

• Renders list of products via shortcode.

class-product-shortcode.php

• Renders a single product by ID.

class-admin-page.php

• Creates settings page and stores options.

class-product-form.php

• Handles:
  • form UI
  • nonce validation
  • POST request wrapper
  • success/error messages

🧹 Security

The plugin uses strict WP security standards:

✔ wp_nonce_field()

✔ sanitize_text_field()

✔ sanitize_url()

✔ esc_html() and esc_attr() when printing

✔ API key stored in WordPress options

✔ No direct file access

🪫 Troubleshooting

❌ "No products available"

• Wrong API URL
• API is down
• API key missing
• Cache contains stale results

❌ "Invalid API Key"

• Token mismatch
• Missing header

❌ "Product not found"

• Incorrect ID
• Product removed

❌ API error: Array

Happens when:

• Python server returns non-JSON
• App crashed or returns HTML error
• Port conflict (already in use)

🤝 Contributing

Pull requests are welcome. Follow:

• WordPress Coding Standards
• OOP architecture
• Proper escaping & sanitization

📜 License

MIT License. You are free to use, modify and distribute.