Service Manager

The Service Manager is a simple schema-based IoC (Inversion of Control) container for TypeScript. It provides a way to manage dependencies and services in your application, making it easier to write modular, testable, and maintainable code.

Features

• Dependency Injection Made Easy: The Service Manager automatically resolves and injects dependencies based on simple service definition schemas
• Instance Management: Swap injections and arguments easily by defining them in the service definition schema
• Singletons galore: All your services will be singletons, no need to worry about misplacing your state
• Post-build Actions: Define your initialization actions directly in the schema
• Lazy Loading: Service modules are imported asynchronously on-demand
• Type Safety: The Service Manager has been meticulously developed to ensure maximum type safety and autocompletion
• Lightweight: Did you know the Service Manager weighs only 6 kB gzipped? It's true!
• Zero Dependencies: The Service Manager has no dependencies, so you can expect it to work even if all other libraries collapse

Getting Started

1. Install the Service Manager package:

   • Using npm

   npm install service-manager

   • Using pnpm

   pnpm add service-manager

   • Using yarn

   yarn add service-manager

2. Define your service classes:

   // MyService.ts
   export default class MyService {
     constructor(private readonly myDependency: MyDependency) {}
   
     // Service methods...
   }
   
   // MyDependency.ts
   export default class MyDependency {
     // Dependency methods...
   }
   
   // MySecondDependency.ts
   export default class MySecondDependency {
     // Dependency methods...
   }

3. Create a map of your services and instances (if you need multiple instances of the same service):

   // services.type.ts
   export type Services = {
     MyService: MyService;
     MyDependency: MyDependency;
     MySecondDependency: MySecondDependency;
   };
   export type Instances = {
     myOtherServiceInstance: MyService;
   };

4. Create a service definition file:

   // serviceDefinitions.ts
   import type { ServiceDefinition } from 'service-manager';
   import type { Services, Instances } from './services.type';
   
   const serviceDefinitions: ServiceDefinition<Services, Instances>[] = [
     {
       serviceClassName: 'MyService',
       serviceInjections: [{ serviceInstanceName: 'MyDependency' }],
       pathToService: async () => import('./MyService'),
     },
     {
       serviceClassName: 'MyDependency',
       pathToService: async () => import('./MyDependency'),
     },
     {
       serviceClassName: 'MySecondDependency',
       pathToService: async () => import('./MySecondDependency'),
     },
     {
       serviceClassName: 'MyService',
       serviceInstanceName: 'myOtherServiceInstance',
       serviceInjections: [{ serviceInstanceName: 'MySecondDependency' }],
       pathToService: async () => import('./MyService'),
     },
   ];
   
   export default serviceDefinitions;

5. Initialize the Service Manager:

   // index.ts
   import { ServiceManager } from 'service-manager';
   import serviceDefinitions from './serviceDefinitions';
   
   const serviceManager = new ServiceManager<Services, Instances>({
     serviceDefinitions,
   });

6. Load and use services:

   // index.ts
   async function main() {
     const myService = await serviceManager.loadService('MyService');
     // Use myService...
     const myServiceInstance = await serviceManager.loadService(
       serviceManager.SERVICES.myServiceInstance
     );
     // Use myServiceInstance...
     const [myDependency, mySecondDependency] =
       await serviceManager.loadServices([
         'MyDependency',
         'MySecondDependency',
       ]);
     // Use myDependency and mySecondDependency...
   }
   
   main();

Additional Information and Examples

For additional information and examples, please refer to the ServiceManager class TSDocs section.

API Reference

For more information about the API, you can check the TSDocs section.

Contributing

Contributions are welcome! If you find any issues or have suggestions for improvement, please open an issue or submit a pull request on the GitHub repository.

License

This project is licensed under the MIT License © Lucas Traba.