DIP Violation
DScheglov opened this issue · 2 comments
Hey, @vovaspace
This line violates Dependcy Inversion Principle:
The ES-module with definition of ApiService
class depends on infrastructure layer: your library brandi
and on the module structue: TOKENS
.
Just move this line to the composition root and everything becomes well again:
import { DependencyModule, injected } from 'brandi';
import { TOKENS } from '../tokens';
import { ApiService } from './ApiService';
export const apiModule = new DependencyModule();
apiModule.bind(TOKENS.apiKey).toConstant('#key9428');
injected(ApiService, TOKENS.apiKey); // << this code should be here
apiModule.bind(TOKENS.apiService).toInstance(ApiService).inTransientScope();
All dependency resolution rules should be placed in single place: composition root (see: Dependency Injection Principles, Practices, and Patterns by Steven van Deursen and Mark Seemann)
And if you are going to move it to the composition root, just add the inject
parameter to the container methods: toFactory
and toInstance
:
import { DependencyModule } from 'brandi';
import { TOKENS } from '../tokens';
import { ApiService } from './ApiService';
export const apiModule = new DependencyModule();
apiModule.bind(TOKENS.apiKey).toConstant('#key9428');
apiModule
.bind(TOKENS.apiService)
.toInstance(ApiService, TOKENS.apiKey)
.inTransientScope();
Hi!
That is great suggestion! I'm working on the next Brandi version and will try to implement that.
This is actually what I'm doing in my library usage of brandi. I'm exporting a set of tokens, a dependency module, and a default set of injected()
registrations that can be used collectively or rebound by the consuming application.