Service

Mark a class as an injectable service with @Service(). Register it under the plugin @Module providers so other components can @Inject it. Constructor injection is not supported.

@Service

@Service() — register an injectable service (singleton in the plugin DI container)
List the class in @Module({ providers: [...] })

@Inject

Use property @Inject only — constructor injection is not supported. @Inject(Service) is same-plugin; @Inject(Service, "other-plugin") is cross-plugin.

@Inject(MyService) — inject from the current plugin
@Inject(MyService, "other-plugin") — inject from another plugin

TSXinject

import {
  Controller,
  Inject,
  PartnerService,
} from "@quan-erp/shared-backend-core";
import { RewardPointService } from "./reward-point.service.js";

@Controller("/reward-point")
export class RewardPointController {
  @Inject(RewardPointService)
  service: RewardPointService;

  // cross-plugin
  @Inject(PartnerService, "base")
  partnerService: PartnerService;
}

Circular service injection

Mutual imports + @Inject(OtherService) can hit ESM TDZ. Use a lazy ref and InstanceType so design:type is not the class.

TSXlazy inject

import { Inject, Service, UserService } from "@quan-erp/shared-backend-core";

@Service()
export class ChangeLogService {
  @Inject(() => UserService)
  userService: InstanceType<typeof UserService>;
}

Example

TSXservice

import { Service } from "@quan-erp/shared-backend-core";

@Service()
export class LocationService {
  async list() {
    // domain logic
  }
}