lib/di

Angular-style dependency injection system.

This module provides a lightweight DI container inspired by Angular's inject() function. Services can inject dependencies from other modules during construction.

Usage

import { inject } from "@core/di";
import { CharacterService } from "@modules/core/characters/character.service";
 
class MyService {
    // Inject during construction - the injection context is set by the module system
    private characterService = inject(CharacterService);
 
    @Server
    async doSomething(ctx: EventContext<[]>) {
        // Use the injected service
        const character = this.characterService.getActiveCharacter(ctx.source);
    }
}

How It Works

1. When modules start, the module system sets an "injection context"
2. Services are instantiated within this context
3. inject() looks up services from the DI container
4. Since modules start in dependency order, dependencies are always available

Important Notes

• inject() can only be called during service construction (in field initializers or constructor)
• You can only inject services from modules that are dependencies of your module
• Circular dependencies are not supported and will throw an error

Interfaces

Interface	Description
InjectionContext	Injection context that tracks the current service being constructed.

Type Aliases

Type Alias	Description
InjectionToken	Token for identifying services in the container. Can be a class constructor or a symbol for interface tokens.
ServiceClass	Constructor type for injectable services. Services must have a parameterless constructor.

Variables

instances

const instances: Map<InjectionToken, unknown>;

Defined in: src/lib/di/container.ts:39

Registry mapping service classes/tokens to their instances.

---

serviceModules

const serviceModules: Map<InjectionToken, string>;

Defined in: src/lib/di/container.ts:45

Registry mapping service classes/tokens to their source module name.

Functions

Function	Description
createInjectionToken	Create an injection token for an interface. Use this when you want to inject an interface rather than a concrete class.
getCurrentContext	Get the current injection context.
inject	Inject a service dependency.
injectClient	Client-side inject function. Throws on missing or inaccessible services.
injectOptional	Try to inject a service, returning undefined if not found.
injectOptionalClient	Client-side injectOptional function.
injectOptionalServer	Server-side injectOptional function.
injectOptionalWeb	Web-specific injectOptional function. Same as regular injectOptional but never throws.
injectServer	Server-side inject function. Throws on missing or inaccessible services.
injectWeb	Web-specific inject function. Returns no-op proxies for missing or inaccessible services.