factoryProvider

function in meocord/common Since 4.1.0

factoryProvider<
  const P extends ProviderToken,
  const I extends readonly ProviderToken[] = [],
>(provider: {
  provide: P
  inject?: I
  useFactory: (...args: Injected<I>) => Provided<P> | Promise<Provided<P>>
}): FactoryProvider<Provided<P>>

Makes a factory provider whose function is typed from its inject list and its token.

Use it in place of a plain { provide, useFactory, inject } object, which works the same at runtime but whose function TypeScript cannot type inside a list: each parameter is what the token in its place provides, and the function must return what provide stands for.

Parameters

Name	Type	Description
`provider`	`{ provide: P inject?: I useFactory: ( ...args: Injected<I> ) => Provided<P> \| Promise<Provided<P>> }`	The token to provide, the tokens to inject, and the function that makes the value.
`provider.provide`	`P`
`provider.inject?`	`I`
`provider.useFactory`	`( ...args: Injected<I> ) => Provided<P> \| Promise<Provided<P>>`

Returns

FactoryProvider<Provided<P>>

The provider, unchanged, for @MeoCord({ providers }) or a testing module's providers.

Examples

TypeScript

@Service()
class Settings { readonly databaseUrl = process.env.DATABASE_URL! }
class Database { constructor(readonly url: string) {} }
export const DATABASE = createToken<Database>('Database')

@MeoCord({
  controllers: [],
  // settings is a Settings, and the function must return a Database
  providers: [factoryProvider({ provide: DATABASE, inject: [Settings], useFactory: settings => new Database(settings.databaseUrl) })],
  clientOptions: { intents: [GatewayIntentBits.Guilds] },
})
class App {}