syncable-entity-runner-and-actions

可同步实体：运行器与操作（第 4/6 步）

目的：对数据库执行迁移操作，并从通用实体正确转译到扁平实体。

何时使用：在完成第 1-3 步（类型、缓存、构建器）之后。集成之前必须完成。

---

快速开始

本步骤创建：

1. 创建操作处理器
2. 更新操作处理器
3. 删除操作处理器
4. 通用到扁平的转换工具

核心模式：每个处理器都有两个阶段：

1. 转译：通用操作 → 扁平操作
2. 执行：扁平操作 → 数据库操作

---

第 1 步：创建操作处理器

文件：src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/my-entity/services/create-my-entity-action-handler.service.ts

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

import { WorkspaceCreateActionHandlerService } from 'src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/workspace-create-action-handler.service';
import { MyEntityEntity } from 'src/engine/metadata-modules/my-entity/entities/my-entity.entity';
import { fromUniversalFlatMyEntityToFlatMyEntity } from 'src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/my-entity/utils/from-universal-flat-my-entity-to-flat-my-entity.util';
import {
  type UniversalCreateMyEntityAction,
  type FlatCreateMyEntityAction,
} from 'src/engine/workspace-manager/workspace-migration/workspace-migration-builder/builders/my-entity/types/workspace-migration-my-entity-action.type';

@Injectable()
export class CreateMyEntityActionHandlerService extends WorkspaceCreateActionHandlerService<
  'myEntity',
  UniversalCreateMyEntityAction,
  FlatCreateMyEntityAction
> {
  constructor(
    @InjectRepository(MyEntityEntity, 'metadata')
    private readonly myEntityRepository: Repository<MyEntityEntity>,
  ) {
    super();
  }

  // Phase 1: Transpile universal action to flat action
  protected transpileUniversalActionToFlatAction(
    universalAction: UniversalCreateMyEntityAction,
    flatEntityMaps: AllFlatEntityMapsByMetadataName,
  ): FlatCreateMyEntityAction {
    return {
      type: 'create',
      metadataName: 'myEntity',
      flatEntity: fromUniversalFlatMyEntityToFlatMyEntity(
        universalAction.universalFlatEntity,
        flatEntityMaps,
      ),
    };
  }

  // Phase 2: Execute flat action against database
  protected async executeForMetadata(
    flatActions: FlatCreateMyEntityAction[],
  ): Promise<void> {
    const flatEntities = flatActions.map((action) => action.flatEntity);

    await this.insertFlatEntitiesInRepository({
      repository: this.myEntityRepository,
      flatEntities,
    });
  }

  protected async executeForWorkspaceSchema(): Promise<void> {
    // No workspace schema changes needed for metadata-only entity
    return;
  }
}

关键辅助方法：

• transpileUniversalActionToFlatAction：将通用转换为扁平
• insertFlatEntitiesInRepository：基类提供的插入辅助方法
• executeForMetadata：元数据数据库操作
• executeForWorkspaceSchema：工作区架构变更（如需要）

---

第 2 步：更新操作处理器

文件：src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/my-entity/services/update-my-entity-action-handler.service.ts

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

import { WorkspaceUpdateActionHandlerService } from 'src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/workspace-update-action-handler.service';
import { MyEntityEntity } from 'src/engine/metadata-modules/my-entity/entities/my-entity.entity';
import { fromUniversalFlatMyEntityToFlatMyEntity } from 'src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/my-entity/utils/from-universal-flat-my-entity-to-flat-my-entity.util';
import { resolveUniversalUpdateRelationIdentifiersToIds } from 'src/engine/workspace-manager/workspace-migration/universal-flat-entity/utils/resolve-universal-relation-identifiers-to-ids.util';

@Injectable()
export class UpdateMyEntityActionHandlerService extends WorkspaceUpdateActionHandlerService<
  'myEntity',
  UniversalUpdateMyEntityAction,
  FlatUpdateMyEntityAction
> {
  constructor(
    @InjectRepository(MyEntityEntity, 'metadata')
    private readonly myEntityRepository: Repository<MyEntityEntity>,
  ) {
    super();
  }

  protected transpileUniversalActionToFlatAction(
    universalAction: UniversalUpdateMyEntityAction,
    flatEntityMaps: AllFlatEntityMapsByMetadataName,
  ): FlatUpdateMyEntityAction {
    const flatEntity = fromUniversalFlatMyEntityToFlatMyEntity(
      universalAction.universalFlatEntity,
      flatEntityMaps,
    );

    // Resolve universal foreign keys in updates to regular IDs
    const flatUpdates = resolveUniversalUpdateRelationIdentifiersToIds({
      metadataName: 'myEntity',
      universalUpdates: universalAction.universalUpdates,
      flatEntityMaps,
    });

    return {
      type: 'update',
      metadataName: 'myEntity',
      flatEntity,
      updates: flatUpdates,
    };
  }

  protected async executeForMetadata(
    flatActions: FlatUpdateMyEntityAction[],
  ): Promise<void> {
    for (const action of flatActions) {
      await this.myEntityRepository.update(
        { id: action.flatEntity.id },
        action.updates,
      );
    }
  }

  protected async executeForWorkspaceSchema(): Promise<void> {
    return;
  }
}

更新专用辅助方法：

• resolveUniversalUpdateRelationIdentifiersToIds：将通用标识符映射回 updates 对象中的常规 ID

---

第 3 步：删除操作处理器

文件：src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/my-entity/services/delete-my-entity-action-handler.service.ts

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

import { WorkspaceDeleteActionHandlerService } from 'src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/workspace-delete-action-handler.service';
import { MyEntityEntity } from 'src/engine/metadata-modules/my-entity/entities/my-entity.entity';
import { fromUniversalFlatMyEntityToFlatMyEntity } from 'src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/my-entity/utils/from-universal-flat-my-entity-to-flat-my-entity.util';

@Injectable()
export class DeleteMyEntityActionHandlerService extends WorkspaceDeleteActionHandlerService<
  'myEntity',
  UniversalDeleteMyEntityAction,
  FlatDeleteMyEntityAction
> {
  constructor(
    @InjectRepository(MyEntityEntity, 'metadata')
    private readonly myEntityRepository: Repository<MyEntityEntity>,
  ) {
    super();
  }

  protected transpileUniversalActionToFlatAction(
    universalAction: UniversalDeleteMyEntityAction,
    flatEntityMaps: AllFlatEntityMapsByMetadataName,
  ): FlatDeleteMyEntityAction {
    // Use base class helper for delete transpilation
    return this.transpileUniversalDeleteActionToFlatDeleteAction({
      universalAction,
      flatEntityMaps,
      fromUniversalFlatEntityToFlatEntity: fromUniversalFlatMyEntityToFlatMyEntity,
    });
  }

  protected async executeForMetadata(
    flatActions: FlatDeleteMyEntityAction[],
  ): Promise<void> {
    const ids = flatActions.map((action) => action.flatEntity.id);

    await this.myEntityRepository.delete(ids);
  }

  protected async executeForWorkspaceSchema(): Promise<void> {
    return;
  }
}

删除专用辅助方法：

• transpileUniversalDeleteActionToFlatDeleteAction：基类提供的辅助方法，处理标准删除转译

---

第 4 步：通用到扁平的转换

文件：src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/my-entity/utils/from-universal-flat-my-entity-to-flat-my-entity.util.ts

import { resolveUniversalRelationIdentifiersToIds } from 'src/engine/workspace-manager/workspace-migration/universal-flat-entity/utils/resolve-universal-relation-identifiers-to-ids.util';
import { type UniversalFlatMyEntity } from 'src/engine/workspace-manager/workspace-migration/universal-flat-entity/types/universal-flat-my-entity.type';
import { type FlatMyEntity } from 'src/engine/metadata-modules/flat-my-entity/types/flat-my-entity.type';
import { type AllFlatEntityMapsByMetadataName } from 'src/engine/metadata-modules/flat-entity/types/all-flat-entity-maps-by-metadata-name.type';

export const fromUniversalFlatMyEntityToFlatMyEntity = (
  universalFlatMyEntity: UniversalFlatMyEntity,
  flatEntityMaps: AllFlatEntityMapsByMetadataName,
): FlatMyEntity => {
  // Resolve universal foreign keys back to regular IDs
  return resolveUniversalRelationIdentifiersToIds({
    metadataName: 'myEntity',
    universalFlatEntity: universalFlatMyEntity,
    flatEntityMaps,
  }) as FlatMyEntity;
};

关键工具：

• resolveUniversalRelationIdentifiersToIds：将通用标识符映射为常规 ID（与 resolveEntityRelationUniversalIdentifiers 相反）

---

操作处理器模式

模式：创建处理器

// 1. Transpile: Universal → Flat
protected transpileUniversalActionToFlatAction(
  universalAction,
  flatEntityMaps,
) {
  return {
    type: 'create',
    metadataName: 'myEntity',
    flatEntity: fromUniversalFlatMyEntityToFlatMyEntity(
      universalAction.universalFlatEntity,
      flatEntityMaps,
    ),
  };
}

// 2. Execute: Flat → Database
protected async executeForMetadata(flatActions) {
  await this.insertFlatEntitiesInRepository({
    repository: this.myEntityRepository,
    flatEntities: flatActions.map(a => a.flatEntity),
  });
}

模式：更新处理器

// Transpile with update-specific resolution
protected transpileUniversalActionToFlatAction(
  universalAction,
  flatEntityMaps,
) {
  const flatEntity = fromUniversalFlatMyEntityToFlatMyEntity(
    universalAction.universalFlatEntity,
    flatEntityMaps,
  );

  const flatUpdates = resolveUniversalUpdateRelationIdentifiersToIds({
    metadataName: 'myEntity',
    universalUpdates: universalAction.universalUpdates,
    flatEntityMaps,
  });

  return { type: 'update', metadataName: 'myEntity', flatEntity, updates: flatUpdates };
}

模式：删除处理器

// Use base class helper
protected transpileUniversalActionToFlatAction(
  universalAction,
  flatEntityMaps,
) {
  return this.transpileUniversalDeleteActionToFlatDeleteAction({
    universalAction,
    flatEntityMaps,
    fromUniversalFlatEntityToFlatEntity: fromUniversalFlatMyEntityToFlatMyEntity,
  });
}

// Delete
protected async executeForMetadata(flatActions) {
  const ids = flatActions.map(a => a.flatEntity.id);
  await this.myEntityRepository.delete(ids);
}

---

检查清单

在进入第 5 步之前：

• 创建操作处理器已实现
• 更新操作处理器已实现
• 删除操作处理器已实现
• 所有处理器都继承了适当的基类
• 所有处理器都实现了 transpileUniversalActionToFlatAction
• 所有处理器都实现了 executeForMetadata
• 已实现 executeForWorkspaceSchema（或返回空）
• 已创建通用到扁平的转换工具
• 创建处理器使用了 insertFlatEntitiesInRepository
• 更新处理器使用了 resolveUniversalUpdateRelationIdentifiersToIds
• 删除处理器使用了 transpileUniversalDeleteActionToFlatDeleteAction
• 删除处理器使用了硬删除（delete()）

---

下一步

操作处理器完成后，请继续： 可同步实体：集成（第 5/6 步）

完整工作流请参见 @creating-syncable-entity 规则。