全球数字权益，一个平台接入。

POST /api/v1/orders
Host: b2b.cardv.net
X-Key-Id: ck_live_••••••••
X-Timestamp: 1790000000
X-Nonce: 9f1c2b7e-4d1a
X-Signature: 5c0e…a91f

{
  "external_order_id": "SHOP-10001",
  "items": [{
    "sku_id": "S000001",
    "quantity": 2,
    "expected_unit_price": "9.25"
  }]
}

// 201 Created · replaying the same reference returns 200
{
  "idempotent_replay": false,
  "order": {
    "order_id": "O-00000042",
    "external_order_id": "SHOP-10001",
    "status": "accepted",
    "currency": "USD",
    "total_amount": "18.5000"
  }
}

// Wallet debit is committed with the order.
// Fulfilment continues asynchronously.

X-CardV-Event: order.succeeded
X-CardV-Delivery: 123
X-CardV-Timestamp: 1790000060
X-CardV-Signature: t=1790000060,v2=…

{
  "event": "order.succeeded",
  "order": {
    "order_id": "O-00000042",
    "status": "succeeded",
    "items": [{ "sku_id": "S000001", "delivery_count": 2 }]
  }
}

// v2 = HMAC-SHA256(secret, "<t>.<delivery>.<event>." + raw_body)