product_number nginx map

cache.conf

# Get product_number from the product availability URI:
#   /api/product/check_availability/{product_number}
# where
#   product_number begins with an alpha character and ends with 7 digits.
map $request_uri $product_number {
    "~^/api/product/check_availability/(?<re_match>[a-zA-Z]\d{7})$"   $re_match;
}