API Reference
API specifications
Review common Issuing API request headers, response envelope, currency and timestamp rules, and response codes.
Use this page before integrating Issuing APIs. All Issuing merchant APIs use POST requests under the /api/v1/merchant base path unless an endpoint page states otherwise.
Request headers
| Header | Type | Required | Description |
|---|---|---|---|
Content-Type | String | Yes | Use application/json;charset=UTF-8. |
ApiKey | String | Yes | Merchant identity credential assigned by Onerway for Issuing API access. |
Response structure
| Field | Type | Description |
|---|---|---|
respCode | String | Response code. 20000 means the request was processed successfully. |
respMsg | String | Response message. |
data | Object / Array | Business data. The value can be null when the request fails. |
Currency
Currency values use the ISO 4217 international standard.
Timezone
Long timestamp fields are UTC timestamps. Query parameters use seconds unless the endpoint page states otherwise; operation, settlement, authorization, and transaction event timestamps can be returned in milliseconds.
Response codes
When the HTTP status code is not 200:
| HTTP status code | Description |
|---|---|
401 Unauthorized | Invalid API credentials. |
403 Forbidden | IP allowlist restriction or insufficient API permissions. |
When the HTTP status code is 200, read the business response code:
| Code | Description |
|---|---|
20000 | Success. |
40000 | Parameter error. |
80000 | Internal service error. Contact Onerway. |
80001 | Cardholder not found. |
80002 | Cardholder email already exists. |
80003 | Incorrect cardholder merchant number. |
80004 | Merchant status is invalid. |
80005 | Merchant has no issuing business. |
80006 | Merchant account not found. |
80007 | Merchant balance is not enough. |
80008 | The recharge amount exceeds the maximum limit. |
80009 | The recharge amount is less than the minimum limit. |
80010 | Duplicate data. |
80011 | Cardholder card count limit. |
81000 | Unauthorized merchant. |
81001 | Business does not exist. |
40004 | System exception: NoHandlerFoundException. |
40005 | System exception: HttpRequestMethodNotSupportedException. |
40013 | System exception: HttpMessageNotReadableException. |
40015 | System exception: HttpMediaTypeNotSupportedException. |