ioc

Description

Inversion of Control container.

Import

import {
  context,
  iocParam,
  IocClass
} from "dreamkit";

Definition

declare const context: {
  register(
    key: any,
    data: {
      value?: any;
      useClass?: any;
      useFactory?: ($context: typeof context, key: any) => any;
      singleton?: boolean;
    },
  ): typeof context;
  unregister(key: any): typeof context;
  resolve(key: any): unknown;
  fork(): typeof context;
};

Examples

Basic usage

import { $route, context, IocClass } from "dreamkit";

abstract class ThirdModel {
  abstract fetch(): string;
}

class MyModel extends IocClass({ ThirdModel }) {
  fetch() {
    return this.thirdModel.fetch();
  }
}

export default $route.path("/").create(() => {
  class ThirdModelImpl extends ThirdModel {
    override fetch() {
      return "resolved";
    }
  }
  const manualModel = new MyModel({ thirdModel: new ThirdModelImpl() });
  const autoModel = context
    .fork()
    .register(ThirdModel, { value: new ThirdModelImpl() })
    .resolve(MyModel);
  return (
    <>
      <p>{manualModel.fetch()}</p>
      <p>{autoModel.fetch()}</p>
    </>
  );
});

Optional

import { context, IocClass, iocParam, ServiceClass } from "dreamkit";

class StringModel {
  toUpperCase(value: string) {
    return value.toUpperCase();
  }
}

class MyModel extends IocClass({
  string: iocParam(StringModel).optional(),
}) {
  toUpperCase(value: string) {
    return this.string?.toUpperCase(value);
  }
}

export class MyService extends ServiceClass({}) {
  onStart() {
    const model1 = new MyModel({});
    const model2 = new MyModel({
      string: {
        toUpperCase(value) {
          return value.toUpperCase();
        },
      },
    });
    const model3 = context
      .fork()
      .register(StringModel, { useFactory: () => new StringModel() })
      .resolve(MyModel);

    console.log({
      model1: model1.toUpperCase("text"), // undefined
      model2: model2.toUpperCase("text"), // "TEXT"
      model3: model3.toUpperCase("text"), // "TEXT"
    });
  }
}