Syncable Entity: Cache & Transform (Step 2/6)

Purpose: Create cache layer and transformation utilities to convert between different entity representations.

When to use: After completing Step 1 (Types & Constants). Required before building validators and action handlers.

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Quick Start

This step creates:

1. Cache service for flat entity maps
2. Entity-to-flat conversion utility
3. Input transform utils (DTO → Universal Flat Entity)

Key principle: Input transform utils must output universal flat entities (with universalIdentifier and foreign keys mapped to universal identifiers).

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Step 1: Create Cache Service

File: src/engine/metadata-modules/flat-my-entity/services/flat-my-entity-cache.service.ts

import { Injectable } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { v4 } from 'uuid';

import { WorkspaceCache } from 'src/engine/twenty-orm/decorators/workspace-cache.decorator';
import { MyEntityEntity } from 'src/engine/metadata-modules/my-entity/entities/my-entity.entity';
import { type FlatMyEntityMaps } from 'src/engine/metadata-modules/flat-my-entity/types/flat-my-entity-maps.type';
import { fromMyEntityEntityToFlatMyEntity } from 'src/engine/metadata-modules/flat-my-entity/utils/from-my-entity-entity-to-flat-my-entity.util';

@Injectable()
export class FlatMyEntityCacheService {
  constructor(
    @InjectRepository(MyEntityEntity, 'metadata')
    private readonly myEntityRepository: Repository<MyEntityEntity>,
  ) {}

  @WorkspaceCache({ flatMapsKey: 'flatMyEntityMaps' })
  async getFlatMyEntityMaps(): Promise<FlatMyEntityMaps> {
    const myEntities = await this.myEntityRepository.find({
      withDeleted: true, // CRITICAL: Include soft-deleted entities
    });

    const flatMyEntities = myEntities.map((entity) =>
      fromMyEntityEntityToFlatMyEntity(entity),
    );