ZeroSettle Upgrade Offers API
Subscription upgrade/downgrade offers
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OpenAPI Specification
openapi: 3.2.0
info:
title: ZeroSettle IAP Cancel Flow Upgrade Offers API
description: The ZeroSettle IAP API powers the iOS, Android, and Flutter SDKs. It enables product catalog fetching, web checkout, entitlement management, subscription lifecycle operations, and StoreKit transaction syncing. All endpoints are authenticated via the `X-ZeroSettle-Key` header.
version: 1.0.0
contact:
name: ZeroSettle Support
email: support@zerosettle.io
url: https://zerosettle.io
servers:
- url: https://api.zerosettle.io/v1
description: Production
security:
- ApiKeyAuth: []
tags:
- name: Upgrade Offers
description: Subscription upgrade/downgrade offers
paths:
/iap/upgrade-offer:
get:
operationId: getUpgradeOffer
summary: Get Upgrade Offer
description: Checks if a user is eligible for a subscription upgrade and returns available upgrade options.
tags:
- Upgrade Offers
parameters:
- name: user_id
in: query
required: true
description: The user's external ID.
schema:
type: string
- name: product_id
in: query
required: false
description: Specific product to check upgrade eligibility for.
schema:
type: string
responses:
'200':
description: Upgrade offer details
content:
application/json:
schema:
$ref: '#/components/schemas/UpgradeOffer'
'401':
$ref: '#/components/responses/Unauthorized'
/iap/upgrade-offer/execute:
post:
operationId: executeUpgradeOffer
summary: Execute Upgrade Offer
description: Executes a subscription upgrade, creating a new payment intent or checkout session for the target product. The old subscription is cancelled with proration when the new payment succeeds.
tags:
- Upgrade Offers
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- user_id
- current_product_id
- target_product_id
properties:
user_id:
type: string
description: The user's external ID.
current_product_id:
type: string
description: The reference ID of the user's current subscription product.
target_product_id:
type: string
description: The reference ID of the product to upgrade to.
responses:
'200':
description: Upgrade initiated
content:
application/json:
schema:
$ref: '#/components/schemas/UpgradeExecuteResponse'
'400':
$ref: '#/components/responses/BadRequest'
'401':
$ref: '#/components/responses/Unauthorized'
'404':
$ref: '#/components/responses/NotFound'
/iap/upgrade-offer/respond:
post:
operationId: respondUpgradeOffer
summary: Respond to Upgrade Offer
description: Records the user's response to an upgrade offer for analytics purposes.
tags:
- Upgrade Offers
requestBody:
required: true
content:
application/json:
schema:
type: object
required:
- user_id
properties:
user_id:
type: string
description: The user's external ID.
accepted:
type: boolean
description: Whether the user accepted the upgrade offer.
variant_id:
type: integer
description: Experiment variant ID, if the upgrade offer is part of an A/B test.
responses:
'200':
description: Response recorded
content:
application/json:
schema:
type: object
properties:
status:
type: string
example: ok
'401':
$ref: '#/components/responses/Unauthorized'
components:
responses:
BadRequest:
description: Invalid request -- missing or malformed parameters.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
NotFound:
description: Resource not found.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
Unauthorized:
description: Invalid or missing API key.
content:
application/json:
schema:
$ref: '#/components/schemas/Error'
schemas:
UpgradeOffer:
type: object
description: Upgrade offer eligibility and options.
properties:
eligible:
type: boolean
description: Whether the user is eligible for an upgrade.
current_product_id:
type: string
description: The user's current subscription product ID.
eligible_upgrades:
type: array
description: Products the user can upgrade to.
items:
type: object
properties:
product_id:
type: string
description: The upgrade target product's reference ID.
display_name:
type: string
description: Product display name.
price:
$ref: '#/components/schemas/Price'
savings_percent:
type: integer
description: Percentage savings compared to the current plan (annualized).
variant_id:
description: Experiment variant ID if the upgrade offer is part of an A/B test.
type:
- integer
- 'null'
Error:
type: object
description: Error response.
properties:
error:
type: string
description: Human-readable error message.
code:
type: string
description: Machine-readable error code (not always present).
required:
- error
Price:
type: object
description: A price in micros (1/1,000,000 of the currency unit).
properties:
amount_micros:
type: integer
description: Price in micros. For example, $4.99 = 4990000.
currency_code:
type: string
description: ISO 4217 currency code (e.g., `USD`).
UpgradeExecuteResponse:
type: object
description: Response from executing an upgrade.
properties:
type:
type: string
enum:
- web_to_web
- storekit_to_web
description: The type of upgrade being performed.
client_secret:
type: string
description: Stripe PaymentIntent client secret for confirming the upgrade payment.
checkout_url:
type: string
description: Fallback checkout URL.
transaction_id:
type: string
description: ZeroSettle transaction ID for the upgrade.
securitySchemes:
ApiKeyAuth:
type: apiKey
in: header
name: X-ZeroSettle-Key
description: Your publishable API key. Use `zs_pk_test_*` for sandbox or `zs_pk_live_*` for production.