fix: make SMS retry side effects idempotent

api/src/billing/billing.service.ts

@@ -19,6 +19,7 @@ export interface UpdateCreditLimitDto {
 export interface CreateAccountTransactionDto {
   tenantId: string;
   transactionType: string;
+  idempotencyKey?: string;
   amountCents?: number;
   balanceAfter?: number;
   relatedType?: string;
@@ -67,6 +68,7 @@ export interface EstimateSmsCostDto {
 
 export interface BillingActionDto {
   tenantId: string;
+  idempotencyKey?: string;
   amountCents?: number;
   relatedType?: string;
   relatedId?: string;
@@ -454,25 +456,46 @@ export class BillingService {
   }
 
   private async applyAccountDelta(data: CreateAccountTransactionDto) {
-    const account = await this.getAccountOrCreate(data.tenantId);
-    const nextBalance = moneyToNumber(account.balanceCents) + (data.amountCents ?? 0);
-    await this.prisma.tenantAccount.update({
-      where: { tenantId: data.tenantId },
-      data: {
-        balanceCents: nextBalance,
-      },
-    });
-
-    return this.prisma.accountTransaction.create({
-      data: {
-        tenantId: data.tenantId,
-        transactionType: data.transactionType,
-        amountCents: data.amountCents ?? 0,
-        balanceAfter: nextBalance,
-        relatedType: data.relatedType,
-        relatedId: data.relatedId,
-        remark: data.remark,
-      },
+    const amountCents = data.amountCents ?? 0;
+    const idempotencyKey = data.idempotencyKey?.trim() || null;
+    return this.prisma.$transaction(async (tx) => {
+      await tx.$executeRaw`SELECT pg_advisory_xact_lock(hashtextextended(${'tenant-account:' + data.tenantId}, 0))`;
+      if (idempotencyKey) {
+        const existing = await tx.accountTransaction.findUnique({ where: { idempotencyKey } });
+        if (existing) {
+          if (
+            existing.tenantId !== data.tenantId
+            || existing.transactionType !== data.transactionType
+            || moneyToNumber(existing.amountCents) !== amountCents
+            || existing.relatedType !== (data.relatedType ?? null)
+            || existing.relatedId !== (data.relatedId ?? null)
+          ) {
+            throw new ConflictException('账务幂等键已用于另一笔交易');
+          }
+          return existing;
+        }
+      }
+      await tx.tenantAccount.upsert({
+        where: { tenantId: data.tenantId },
+        update: {},
+        create: { tenantId: data.tenantId, balanceCents: 0, creditCents: 0, status: 'active' },
+      });
+      const account = await tx.tenantAccount.update({
+        where: { tenantId: data.tenantId },
+        data: { balanceCents: { increment: amountCents } },
+      });
+      return tx.accountTransaction.create({
+        data: {
+          tenantId: data.tenantId,
+          transactionType: data.transactionType,
+          idempotencyKey,
+          amountCents,
+          balanceAfter: account.balanceCents,
+          relatedType: data.relatedType,
+          relatedId: data.relatedId,
+          remark: data.remark,
+        },
+      });
     });
   }
 }