Add one-time product to upcoming order

Adds a one-time product (one-off) to a specific upcoming billing attempt for a membership contract. The product will be included only in the specified order and will not become part of the recurring subscription.

Full behavior, validation rules, and side effects

Key Features:

• One-Time Addition: Product added to single order only
• Billing Cycle Targeting: Specify exact order to add item to
• No Subscription Impact: Doesn’t change recurring items
• Instant Upsell: Add products between regular billing cycles
• Customer Flexibility: Allow members to add extras to next order
• Activity Logging: Tracks who added the item (merchant vs API)

Required Parameters:

• Contract ID: Target subscription contract
• Billing Attempt ID: Specific upcoming order to add item to
• Variant ID: Shopify product variant to add
• Variant Handle: Product handle for identification

How It Works:

1. Validates contract exists and belongs to shop
2. Checks if contract is not frozen (minimum cycles)
3. Verifies billing attempt is upcoming (not already processed)
4. Adds variant to the specified billing attempt
5. Returns updated list of all one-offs for the contract
6. Logs activity for audit trail

Use Cases:

• Customer wants to add a bonus product to next delivery
• Merchant offers limited-time add-on to existing members
• Trial/sample products added to specific orders
• Holiday specials or seasonal items
• Promotional gifts or rewards
• One-time upsells in customer portal

Business Rules:

• Item added only to specified billing attempt
• Cannot add to past or completed orders
• Contract must not be frozen/minimum cycle locked
• Duplicate items increment quantity

Authentication: Requires API key authentication via X-API-Key header or api_key parameter

PUT /api/external/v2/subscription-contract-one-offs-by-contractId-and-billing-attempt-id

Add one-time product to upcoming order

cURL

curl --request PUT \
  --url https://membership-admin.appstle.com/api/external/v2/subscription-contract-one-offs-by-contractId-and-billing-attempt-id

200

Example

[
  {
    "shop": "my-store.myshopify.com",
    "id": 789,
    "billingAttemptId": 123,
    "subscriptionContractId": 123,
    "variantId": 123,
    "variantHandle": "<string>"
  }
]

Headers

X-API-Key · string

Query Parameters

api_key · string

API Key (Deprecated - Use Header X-API-Key instead)

contractId · integer<int64> · required

Subscription contract ID

billingAttemptId · integer<int64> · required

Billing attempt ID to add the item to

variantId · integer<int64> · required

Product variant ID to add

variantHandle · string · required

Product handle for identification

Response

200

application/json

One-off product successfully added, returns updated list of all one-offs

shop · string · required

Shop domain identifier

Example:

"my-store.myshopify.com"

id · integer<int64>

Unique identifier of the one-off item

Example:

789

billingAttemptId · integer<int64>

Associated billing attempt ID

subscriptionContractId · integer<int64>

Associated subscription contract ID

variantId · integer<int64>

Shopify product variant ID of the one-off item

variantHandle · string

Product variant handle for the one-off item