OPay Cashier API
The OPay Cashier API is the primary merchant payment API behind OPay Checkout. It exposes a hosted Express Checkout endpoint (cashier/create returning a cashierUrl), server-to-server payment creation for 3DS bank cards, bank transfer, bank USSD, bank account, POS, OPay wallet QR, and reference code payments, plus status queries, cancel, refund, and refund-status operations. Authentication uses an Authorization Bearer token — the public key for cashier/create and an HMAC-SHA512 signature over the JSON body (signed with the merchant's private key) for all other endpoints — along with a MerchantId header.
OPay Cashier API is one of 3 APIs that OPay publishes on the APIs.io network, described by a machine-readable OpenAPI specification.
Tagged areas include Payments, Cashier, Checkout, Cards, and Bank Transfer. The published artifact set on APIs.io includes API documentation, a getting-started guide, authentication docs, an API reference, and an OpenAPI specification.
This API exposes 2 operations across 2 paths, and defines 10 schemas. It is described by OpenAPI 3.0.3, at version 1.0.
Requests are made against 2 base URLs: https://liveapi.opaycheckout.com/api/v1/international, https://testapi.opaycheckout.com/api/v1/international.
Metadata
The identity and technical contract details declared by the specification.
Authentication & Security 2
OPay Cashier API declares
2 security schemes
for authenticating requests.
It accepts HTTP bearer tokens (PublicKeyAuth).
It accepts HTTP bearer tokens (SignatureAuth).
PublicKeyAuth— Bearer token = merchant public key (used for cashier/create).SignatureAuth— Bearer token = HMAC-SHA512 of the JSON request body signed with the merchant private key.
Paths & Operations 2
Across 2 paths, the API surfaces 2 operations — 2 POST. Each is listed below with its method, path, parameters, and response codes.
Hosted Express Checkout and order status.
Schemas 10
The contract defines 10 schemas that model the data the API accepts and returns. The most detailed are CashierCreateRequest (14 properties), UserInfo (4 properties), PaymentStatusRequest (3 properties), ApiEnvelope (2 properties). Each schema is shown below with its type and property counts.
Specification
The full machine-readable OpenAPI contract behind this narrative.
Source
More from OPay 2
Other APIs OPay publishes across the network.
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