Handling Callbacks

The onComplete Callback

The onComplete callback fires when the payment flow finishes — either successfully or with an error.

import { PaymentResultStatus } from '@inflow_pay/sdk';

onComplete: (result) => {
  switch (result.status) {
    case PaymentResultStatus.SUCCESS:
      console.log('Payment successful:', result.paymentId);
      // Redirect, show confirmation, etc.
      break;

    case PaymentResultStatus.FAILED:
      console.error('Payment failed:', result.error?.message);
      if (result.error?.retryable) {
        // Customer can try again
      }
      break;
  }
}

Payment Result Object

interface PaymentResult {
  status: 'SUCCESS' | 'FAILED';
  paymentId: string;
  error?: {
    code: string;       // e.g. 'THREE_DS_FAILED', 'PAYMENT_PROCESSING_ERROR'
    message: string;    // User-friendly message (safe to display)
    retryable: boolean; // Whether the customer can try again
  };
}

Error Codes

Code	Description	Retryable
`THREE_DS_FAILED`	3DS authentication failed	Yes
`PAYMENT_PROCESSING_ERROR`	General processing error	Yes

Error messages in result.error.message are user-friendly and safe to display directly to the customer.

Other Callbacks

Callback	When it fires
`onReady`	Card form is mounted and ready for input
`onChange(state)`	Form validation state changes. `state.complete` is `true` when all fields are valid
`onError(error)`	SDK-level error (network issues, initialization problems)

Best Practice: Verify Server-Side

Always verify the payment status on your server via the API or webhooks. Do not rely solely on the client-side callback — it can be spoofed.

onComplete: async (result) => {
  if (result.status === PaymentResultStatus.SUCCESS) {
    // Verify on your backend
    const response = await fetch(`/api/verify-payment/${result.paymentId}`);
    const { verified } = await response.json();
    if (verified) {
      window.location.href = '/confirmation';
    }
  }
}

The SDK API may evolve. Refer to the npm package for the latest callback types and error codes.