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Once Gcashier Pay’s compliance team finishes reviewing a merchant access application submitted via sp1101, the platform posts a notification to the callbackUrl you registered in that request. This webhook delivers the definitive outcome of the review — including your assigned merchantNo and the token you will use to authenticate all subsequent API calls on behalf of that merchant. Your endpoint must accept an HTTP POST with a JSON body and respond with HTTP 200 to acknowledge receipt.
Store the merchantNo and token fields from this notification securely. Every subsequent Gcashier Pay API call for this merchant requires these credentials. Treat the token as a secret — do not log it or expose it in client-side code.

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Invocation Details

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Webhook Payload Fields

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string(32)
required
Gcashier Pay’s internal business serial number for the application. Matches the bizFlow returned in the sp1101 synchronous response. Use this to correlate the notification with the original submission. M
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string(32)
Your original merchant order number, echoed from the sp1101 request. Present only if you supplied it at submission time. O
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string(6)
required
Review outcome code. M
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string(255)
required
Human-readable description of the outcome. On success, this is "Success". On failure or when supplementary documents are needed, this contains a JSON-formatted detail string describing what is required or what went wrong. M
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string(32)
required
Your Gcashier Pay-assigned merchant identifier. Present on successful approval (code=S00000). You must include this in all future API requests for this merchant. M
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string(255)
required
The merchant’s English legal name as recorded by Gcashier Pay, confirming the entity that was approved. M
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string(32)
required
The authorisation token for this merchant. Present on successful approval (code=S00000). You must pass this token in the authentication header of all subsequent API calls made on behalf of this merchant. M

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Webhook Payload Example

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Successful Approval

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Supplementary Documents Required

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Handling the Notification

If the code field is 80000, Gcashier Pay is requesting supplementary or corrected documents. You must call sp1102 with addMaterial set to "1" and provide the requested files in the reMaterial object. The message field will contain a JSON string describing exactly which documents are required. Do not treat 80000 as a final rejection — it is an actionable request that you can resolve.
Persist the merchantNo and token immediately upon receiving a successful (S00000) notification. These values are essential for all downstream operations — including payment initiation, refunds, and settlement queries — and are not re-sent automatically if lost.
Your callbackUrl endpoint should return HTTP 200 as quickly as possible. If you need to perform time-consuming operations (such as database writes or downstream notifications), acknowledge receipt first and process asynchronously. Gcashier Pay may retry delivery if your endpoint does not respond within the expected window.

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Callback Response

Your server must respond with HTTP status 200 and a plain acknowledgement body to confirm receipt. No specific response JSON schema is required — Gcashier Pay treats any 200 response as a successful delivery acknowledgement.