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Merged
mdabubakkarhq merged 1 commit into from
Sep 15, 2026
Merged

Harden payment and refund idempotency #2

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104 changes: 74 additions & 30 deletions modules/gateways/sslcommerz/lib/Ledger.php
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Original file line number Diff line number Diff line change
Expand Up @@ -163,30 +163,42 @@ public function upsertFromGateway(array $transaction, $sessionKey = null)
{
if (empty($transaction['tran_id'])) { return false; }
$tranId = (string)$transaction['tran_id'];
$currency = strtoupper(isset($transaction['currency_type']) ? (string)$transaction['currency_type'] : (isset($transaction['currency']) ? (string)$transaction['currency'] : ''));
$currency = strtoupper(trim(isset($transaction['currency_type']) ? (string)$transaction['currency_type'] : (isset($transaction['currency']) ? (string)$transaction['currency'] : '')));
$invoiceAmount = isset($transaction['currency_amount']) && (float)$transaction['currency_amount'] > 0
? (float)$transaction['currency_amount'] : (isset($transaction['amount']) ? (float)$transaction['amount'] : 0);
? (float)$transaction['currency_amount'] : 0;
$bdtAmount = isset($transaction['amount']) && (float)$transaction['amount'] > 0 ? (float)$transaction['amount'] : 0;
if ($invoiceAmount <= 0 && $currency === 'BDT') { $invoiceAmount = $bdtAmount; }
$safeTransaction = class_exists('SslCommerzSupport') ? SslCommerzSupport::redact($transaction) : $transaction;
$fields = array(
'invoice_id'=>isset($transaction['value_a'])?(int)$transaction['value_a']:0,
'val_id'=>isset($transaction['val_id'])?$transaction['val_id']:null,
'bank_tran_id'=>isset($transaction['bank_tran_id'])?$transaction['bank_tran_id']:null,
'sessionkey'=>$sessionKey ?: (isset($transaction['sessionkey'])?$transaction['sessionkey']:null),
'status'=>strtolower(isset($transaction['status'])?$transaction['status']:'unknown'),
'currency'=>$currency,'invoice_amount'=>$invoiceAmount,
'bdt_amount'=>isset($transaction['amount'])?(float)$transaction['amount']:0,
'currency_rate_bdt'=>$invoiceAmount > 0 && isset($transaction['amount']) ? round((float)$transaction['amount']/$invoiceAmount,8) : 0,
'card_no'=>isset($transaction['card_no'])?$transaction['card_no']:null,
'card_type'=>isset($transaction['card_type'])?$transaction['card_type']:null,
'card_brand'=>isset($transaction['card_brand'])?$transaction['card_brand']:null,
'card_issuer'=>isset($transaction['card_issuer'])?$transaction['card_issuer']:null,
'risk_level'=>isset($transaction['risk_level'])?(int)$transaction['risk_level']:0,
'risk_title'=>isset($transaction['risk_title'])?$transaction['risk_title']:null,
'raw_response'=>json_encode($safeTransaction),
);
$fields = array('raw_response'=>json_encode($safeTransaction));
if (isset($transaction['value_a']) && (int)$transaction['value_a'] > 0) { $fields['invoice_id'] = (int)$transaction['value_a']; }
foreach (array('val_id','bank_tran_id') as $identifier) {
if (isset($transaction[$identifier]) && trim((string)$transaction[$identifier]) !== '') {
$fields[$identifier] = trim((string)$transaction[$identifier]);
}
}
$resolvedSessionKey = trim((string)($sessionKey !== null ? $sessionKey : (isset($transaction['sessionkey']) ? $transaction['sessionkey'] : '')));
if ($resolvedSessionKey !== '') { $fields['sessionkey'] = $resolvedSessionKey; }
if (isset($transaction['status']) && trim((string)$transaction['status']) !== '') {
$fields['status'] = strtolower(trim((string)$transaction['status']));
}
if ($currency !== '') { $fields['currency'] = $currency; }
if ($invoiceAmount > 0) { $fields['invoice_amount'] = $invoiceAmount; }
if ($bdtAmount > 0) { $fields['bdt_amount'] = $bdtAmount; }
if ($invoiceAmount > 0 && $bdtAmount > 0) {
$fields['currency_rate_bdt'] = $currency === 'BDT' ? 1 : round($bdtAmount/$invoiceAmount, 8);
}
foreach (array('card_no','card_type','card_brand','card_issuer','risk_title') as $detail) {
if (isset($transaction[$detail]) && trim((string)$transaction[$detail]) !== '') {
$fields[$detail] = $transaction[$detail];
}
}
if (isset($transaction['risk_level']) && is_numeric($transaction['risk_level'])) {
$fields['risk_level'] = (int)$transaction['risk_level'];
}
$existing = $this->find($tranId);
if ($existing) { return $this->update($tranId, $fields); }
if ($fields['invoice_id'] <= 0 || $fields['invoice_amount'] <= 0 || $currency === '') { return false; }
if (!isset($fields['invoice_id'], $fields['invoice_amount'], $fields['currency'])
|| $fields['invoice_id'] <= 0 || $fields['invoice_amount'] <= 0 || $fields['currency'] === '') { return false; }
$fields['tran_id'] = $tranId;
return $this->begin($fields);
}
Expand Down Expand Up @@ -274,12 +286,6 @@ public function reserveRefund(array $request)
$currency = strtoupper((string)$request['source_currency']);
$sourceAmount = round((float)$request['source_amount'], 2);
$baseRefunded = round((float)$payment->refunded_bdt, 2);
$recentSuccess = \WHMCS\Database\Capsule::table(self::REFUND_TABLE)
->where('payment_tran_id', $payment->tran_id)->where('source_currency', $currency)
->where('source_amount', $sourceAmount)->whereIn('status', array('success','processing'))
->where('updated_at', '>=', date('Y-m-d H:i:s', time() - 300))->orderBy('id', 'desc')->first();
if ($recentSuccess) { $recentSuccess->replay = true; return $recentSuccess; }

$requestKey = hash('sha256', $payment->tran_id . '|' . $currency . '|' . number_format($sourceAmount,2,'.','') . '|' . number_format($baseRefunded,2,'.',''));
$existing = \WHMCS\Database\Capsule::table(self::REFUND_TABLE)->where('request_key', $requestKey)->lockForUpdate()->first();
if ($existing) {
Expand All @@ -306,6 +312,33 @@ public function reserveRefund(array $request)
});
}

public function recoverRefund(array $request)
{
$this->ensureSchema();
if ($this->adapter) {
return method_exists($this->adapter, 'recoverRefund') ? $this->adapter->recoverRefund($request) : null;
}
$payment = \WHMCS\Database\Capsule::table(self::TABLE)
->where(function ($query) use ($request) {
$query->where('tran_id', (string)$request['payment_identifier'])
->orWhere('bank_tran_id', (string)$request['payment_identifier']);
})->first();
if (!$payment) { return null; }
$candidate = \WHMCS\Database\Capsule::table(self::REFUND_TABLE)
->where('payment_tran_id', $payment->tran_id)
->where('invoice_id', (int)$request['invoice_id'])
->where('source_currency', strtoupper((string)$request['source_currency']))
->where('source_amount', round((float)$request['source_amount'], 2))
->whereIn('status', array('success','processing'))
->whereNotNull('refund_ref_id')->orderBy('id', 'desc')->first();
if (!$candidate || trim((string)$candidate->refund_ref_id) === '') { return null; }
$recorded = \WHMCS\Database\Capsule::table('tblaccounts')
->where('transid', (string)$candidate->refund_ref_id)->exists();
if ($recorded) { return null; }
$candidate->replay = true;
return $candidate;
}

public function finalizeRefund($refundTransId, array $result)
{
$this->ensureSchema();
Expand Down Expand Up @@ -358,10 +391,13 @@ private function migrateExistingTable($capsule)
try {
$columns = $capsule::select("SHOW COLUMNS FROM `" . self::TABLE . "`");
$names = array();
foreach ($columns as $column) { $names[] = $column->Field; }
$capsule::statement("ALTER TABLE `" . self::TABLE . "` MODIFY `card_no` VARCHAR(80) NULL");
$capsule::statement("ALTER TABLE `" . self::TABLE . "` MODIFY `bank_tran_id` VARCHAR(100) NULL");
$capsule::statement("ALTER TABLE `" . self::TABLE . "` MODIFY `val_id` VARCHAR(100) NULL");
$byName = array();
foreach ($columns as $column) { $names[] = $column->Field; $byName[$column->Field] = $column; }
foreach (array('card_no'=>80, 'bank_tran_id'=>100, 'val_id'=>100) as $columnName => $length) {
if (isset($byName[$columnName]) && $this->stringColumnNeedsWidening($byName[$columnName], $length)) {
$capsule::statement("ALTER TABLE `" . self::TABLE . "` MODIFY `" . $columnName . "` VARCHAR(" . $length . ") NULL");
}
}
if (in_array('invoice_amount', $names, true) && in_array('bdt_amount', $names, true)) {
$capsule::statement("UPDATE `" . self::TABLE . "` SET `currency_rate_bdt` = `bdt_amount` / `invoice_amount` WHERE `currency_rate_bdt` = 0 AND `invoice_amount` > 0 AND `bdt_amount` > 0");
}
Expand All @@ -381,6 +417,14 @@ private function migrateExistingTable($capsule)
}
}

private function stringColumnNeedsWidening($column, $minimumLength)
{
$type = isset($column->Type) ? strtolower((string)$column->Type) : '';
$nullable = isset($column->Null) && strtoupper((string)$column->Null) === 'YES';
if (!preg_match('/^varchar\((\d+)\)/', $type, $matches)) { return true; }
return (int)$matches[1] < (int)$minimumLength || !$nullable;
}

private function ensureRefundTable($capsule)
{
if ($capsule::schema()->hasTable(self::REFUND_TABLE)) { return; }
Expand Down
38 changes: 27 additions & 11 deletions modules/gateways/sslcommerz/lib/PaymentProcessor.php
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Original file line number Diff line number Diff line change
Expand Up @@ -84,23 +84,23 @@ public function process(array $notification, $source)
'raw_response' => json_encode(SslCommerzSupport::redact($validation)),
));

foreach (array($tranId, $bankTranId) as $candidate) {
$existingInvoice = call_user_func($this->callbacks['find_transaction'], $candidate);
if ($existingInvoice !== null) {
if ((int) $existingInvoice === $invoiceId) {
$this->safeMarkPaid($tranId);
return $this->finish('duplicate', $invoiceId, 'Already Processed', array('transaction_id' => $candidate));
}
return $this->finish('rejected', $invoiceId, 'Transaction Used By Another Invoice', array('transaction_id' => $candidate, 'existing_invoice' => $existingInvoice));
}
}
$existingResult = $this->existingTransactionResult($tranId, $bankTranId, $invoiceId);
if ($existingResult !== null) { return $existingResult; }

$claim = $this->ledger->claim($tranId);
if ($claim === 'held') {
return $this->finish('retry', $invoiceId, 'Settlement Is Being Processed', array('tran_id' => $tranId));
}
if ($claim === 'unavailable') {
$this->log('Ledger Unavailable - WHMCS Guards Active', array('tran_id' => $tranId, 'invoice_id' => $invoiceId));
return $this->finish('retry', $invoiceId, 'Settlement Exclusivity Unavailable', array('tran_id' => $tranId));
}

$existingResult = $this->existingTransactionResult($tranId, $bankTranId, $invoiceId);
if ($existingResult !== null) {
if ($existingResult['code'] === 'rejected') {
try { $this->ledger->release($tranId); } catch (Throwable $ignored) {}
}
return $existingResult;
}

try {
Expand Down Expand Up @@ -131,6 +131,22 @@ private function safeUpdate($tranId, array $fields)
}
}

private function existingTransactionResult($tranId, $bankTranId, $invoiceId)
{
foreach (array($tranId, $bankTranId) as $candidate) {
$existingInvoice = call_user_func($this->callbacks['find_transaction'], $candidate);
if ($existingInvoice === null) { continue; }
if ((int) $existingInvoice === (int) $invoiceId) {
$this->safeMarkPaid($tranId);
return $this->finish('duplicate', $invoiceId, 'Already Processed', array('transaction_id' => $candidate));
}
return $this->finish('rejected', $invoiceId, 'Transaction Used By Another Invoice', array(
'transaction_id' => $candidate, 'existing_invoice' => $existingInvoice,
));
}
return null;
}

private function safeMarkPaid($tranId)
{
try { $this->ledger->markPaid($tranId); } catch (Throwable $error) {
Expand Down
16 changes: 14 additions & 2 deletions modules/gateways/sslcommerz/lib/RefundService.php
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Original file line number Diff line number Diff line change
Expand Up @@ -56,8 +56,20 @@ public function refund(array $params)
throw new RuntimeException('The captured bank transaction ID is unavailable.');
}

$sourceAmount = isset($params['amount']) ? $params['amount'] : 0;
$recoverable = $this->ledger->recoverRefund(array(
'payment_identifier'=>$transId,'invoice_id'=>$invoiceId,
'source_amount'=>$sourceAmount,'source_currency'=>$currency,
));
if ($recoverable && !empty($recoverable->refund_ref_id)) {
return array(
'status'=>'success','transid'=>(string)$recoverable->refund_ref_id,
'rawdata'=>array('status'=>'idempotent_recovery'),
);
}

$refundBdt = SslCommerzPaymentRules::refundAmountBdt(
isset($params['amount']) ? $params['amount'] : 0,
$sourceAmount,
isset($capture['currency']) ? $capture['currency'] : $currency,
isset($capture['invoice_amount']) ? $capture['invoice_amount'] : 0,
isset($capture['bdt_amount']) ? $capture['bdt_amount'] : 0,
Expand All @@ -70,7 +82,7 @@ public function refund(array $params)
$refundTransId = SslCommerzSupport::refundTransactionId($invoiceId);
$reservation = $this->ledger->reserveRefund(array(
'payment_identifier'=>$transId,'invoice_id'=>$invoiceId,
'source_amount'=>isset($params['amount'])?$params['amount']:0,'source_currency'=>$currency,
'source_amount'=>$sourceAmount,'source_currency'=>$currency,
'desired_bdt'=>$refundBdt,'refund_trans_id'=>$refundTransId,
));
$refundTransId = (string)$reservation->refund_trans_id;
Expand Down