perf: expand gateway capacity and prevent receipt replay

api/src/send-chain/send-downstream-delivery.service.ts

@@ -1,6 +1,6 @@
 import { BadRequestException, HttpException, HttpStatus, Logger, NotFoundException } from '@nestjs/common';
 import { Prisma } from '@prisma/client';
-import { createHash } from 'node:crypto';
+import { createHash, randomUUID } from 'node:crypto';
 import { BillingService } from '../billing/billing.service';
 import { moneyToNumber } from '../common/money';
 import type { OpenApiService } from '../open-api/open-api.service';
@@ -28,6 +28,10 @@ export class SendDownstreamDeliveryService {
   ) {}
 
   async handleUplink(data: GatewayUplinkEventDto) {
+	if (data.eventId) {
+	  const existing = await this.prisma.smsUplinkMessage.findUnique({ where: { eventId: data.eventId } });
+	  if (existing) return existing;
+	}
     const channel = await this.prisma.smsChannel.findUnique({ where: { id: data.channelId } });
     if (!channel) {
       throw new NotFoundException('SMS channel not found');
@@ -35,6 +39,7 @@ export class SendDownstreamDeliveryService {
     const match = await this.facade.resolveUplinkMatch(data, channel);
     const record = await this.prisma.smsUplinkMessage.create({
       data: {
+		eventId: data.eventId,
         tenantId: match.tenantId,
         applicationId: match.applicationId,
         messageRecordId: match.messageRecordId,
@@ -276,21 +281,40 @@ export class SendDownstreamDeliveryService {
     if (!deliveryAllowed) {
       return delivery;
     }
+    const claimId = `api-direct:${process.pid}:${randomUUID()}`;
+    const claim = await this.prisma.cmppDownstreamDelivery.updateMany({
+      where: { id: delivery.id, status: 'pending' },
+      data: {
+        status: 'dispatching',
+        connectionId: claimId,
+        ackDeadlineAt: new Date(Date.now() + 30_000),
+        nextRetryAt: null,
+        lastError: null,
+      },
+    });
+    if (claim.count !== 1) {
+      return this.prisma.cmppDownstreamDelivery.findUnique({ where: { id: delivery.id } });
+    }
     try {
       const result = await this.facade.postGatewayControl(
         data.deliveryType === 'receipt' ? '/downstream/receipt' : '/downstream/uplink',
-        { deliveryId: delivery.id, ...payload },
+        { deliveryId: delivery.id, claimId, ...payload },
       ) as GatewayControlDeliveryResult;
       if (result.sent || result.delivered) {
-        await this.facade.markDownstreamDeliverySent({ id: delivery.id, ...result });
+        await this.facade.markDownstreamDeliverySent({ id: delivery.id, claimId, ...result });
       } else if (result.reasonCode === 'SUBMIT_RESPONSE_PENDING') {
-        return delivery;
+        await this.facade.markDownstreamDeliveryFailed(
+          delivery.id,
+          downstreamControlFailureMessage(result),
+          'claim_released',
+          { id: delivery.id, claimId, ...result },
+        );
       } else {
         await this.facade.markDownstreamDeliveryFailed(
           delivery.id,
           downstreamControlFailureMessage(result),
           result.retryable === false ? 'unrecoverable' : 'send_failed',
-          { id: delivery.id, ...result },
+          { id: delivery.id, claimId, ...result },
         );
       }
     } catch (error) {