Import and update products in a BigCommerce store via the Catalog API

Steps

1. Authenticate requests with the store hash and API token using headers X-Auth-Token and Content-Type: application/json; base URL is https://api.bigcommerce.com/stores/{store_hash}/v3
2. Create a product via POST /catalog/products with required fields name, type (physical or digital), weight, and price; receive the product id in the response
3. Add variants by POSTing to /catalog/products/{product_id}/variants with option_values array referencing previously created option and option value IDs, plus sku, price, and inventory_level
4. Upload a product image via POST /catalog/products/{product_id}/images with image_url pointing to a publicly accessible image or multipart form upload with image_file
5. Batch-update multiple products using PUT /catalog/products with an array payload (up to 10 items per request) to reduce API call volume for catalog refreshes
6. Retrieve products with GET /catalog/products using query parameters include=variants,images,custom_fields to fetch related data in a single call