feat: implement automated data retention cron job (7.5.3)

backend/package.json

@@ -25,6 +25,7 @@
     "@nestjs/jwt": "^11.0.2",
     "@nestjs/passport": "^11.0.5",
     "@nestjs/platform-express": "^11.0.1",
+    "@nestjs/schedule": "^6.1.1",
     "@nestjs/swagger": "^11.2.4",
     "@nestjs/typeorm": "^11.0.0",
     "@types/multer": "^2.0.0",

backend/src/app.module.ts

@@ -8,6 +8,7 @@ import { DonationsModule } from './donations/donations.module';
 import { User } from './auth/entities/user.entity';
 import { Donation } from './donations/entities/donation.entity';
 import { CacheModule } from '@nestjs/cache-manager';
+import { ScheduleModule } from '@nestjs/schedule';
 import * as redisStore from 'cache-manager-redis-store';
 
 @Module({
@@ -22,7 +23,10 @@ import * as redisStore from 'cache-manager-redis-store';
     // 1. Load .env variables
     ConfigModule.forRoot({ isGlobal: true }),
 
-    // 2. Connect to Postgres (using variables from docker-compose)
+    // 2. Enable Cron Jobs
+    ScheduleModule.forRoot(),
+
+    // 3. Connect to Postgres (using variables from docker-compose)
     TypeOrmModule.forRoot({
       type: 'postgres',
       host: process.env.DATABASE_HOST || 'postgres',

backend/src/donations/donations.service.ts

@@ -2,6 +2,8 @@ import { Inject, Injectable, Logger, NotFoundException, BadRequestException, For
 import { InjectRepository } from '@nestjs/typeorm';
 import { Repository } from 'typeorm';
 import { CreateDonationDto, ClaimDonationDto } from './dto/donations.dto';
+import { Cron, CronExpression } from '@nestjs/schedule';
+import { LessThan } from 'typeorm';
 import { Donation, DonationStatus } from './entities/donation.entity';
 import { User, UserRole } from '../auth/entities/user.entity';
 import { CACHE_MANAGER } from '@nestjs/cache-manager';
@@ -355,4 +357,30 @@ export class DonationsService {
     return newBadges;
   }
 
+  @Cron('CronExpression.EVERY_DAY_AT_MIDNIGHT')
+  async handleDataRetentionPolicy() {
+    this.logger.log('Running Data Retention Cron Job...');
+
+    const thirtyDaysAgo = new Date();
+    thirtyDaysAgo.setDate(thirtyDaysAgo.getDate() - 30);
+
+    try {
+      const oldDonations = await this.donationsRepository.find({
+        where: {
+          status: DonationStatus.DELIVERED,
+          deliveredAt: LessThan(thirtyDaysAgo),
+        },
+      });
+
+      if (oldDonations.length > 0) {
+        await this.donationsRepository.remove(oldDonations);
+        await this.invalidateCache();
+        this.logger.log(`Successfully deleted ${oldDonations.length} old donations older than 30 days.`);
+      } else {
+        this.logger.log('No old data found to archive today.');
+      }
+    } catch (error: any) {
+      this.logger.error('Failed to run data retention job', error.stack);
+    }
+  }
 }