Add a Cloud Sub-Service

The Cloud module uses a facade pattern: CloudController → CloudService (orchestrator) → specialized sub-services. Each sub-service handles one feature domain.

Existing Sub-Services

Steps

1. •Create the sub-service at src/modules/cloud/cloud.{feature}.service.ts:

import { Injectable } from '@nestjs/common';
import { CloudS3Service } from './cloud.s3.service';

@Injectable()
export class Cloud{Feature}Service {
  constructor(
    private readonly CloudS3Service: CloudS3Service,
    // inject other sub-services or RedisService as needed
  ) {}

  async FeatureMethod(params, user: UserContext): Promise<ResultType> {
    // Use this.CloudS3Service for S3 operations
  }
}

1. •

   Register in cloud.module.ts — Add to both providers and exports arrays

2. •

   Inject into CloudService — Add as a private readonly constructor dependency

3. •

   Add delegation methods in CloudService:

async FeatureMethod(model, user, idempotencyKey?) {
  // Cross-cutting concerns: auth checks, encrypted folder access, idempotency
  const cached = await this.GetIdempotentResult(user.Id, 'feature', idempotencyKey);
  if (cached !== undefined) return cached;

  const result = await this.CloudFeatureService.FeatureMethod(model, user);

  await this.SetIdempotentResult(user.Id, 'feature', idempotencyKey, result);
  return result;
}

1. •Add controller endpoints for the new feature in cloud.controller.ts

Key Conventions

• •Sub-services inject CloudS3Service for S3 operations, never use the AWS SDK directly
• •The main CloudService handles cross-cutting concerns (auth, encrypted folder checks, idempotency caching)
• •Controller stays thin — one method call to CloudService per endpoint
• •Custom headers: x-folder-session, x-folder-passphrase, idempotency-key