Access custom logger in AppModule - nestjs

Question

I replaced the nestjs logger with a custom for having it also for bootstrap messages.
This is the code i have used to instantiate it
const logger = CustomLoggerModule.createLogger();
try {
const app = await NestFactory.create(AppModule, {
logger,
});
} catch (e) {
logger.error(e)
}
createLogger is a static method of the CustomLoggerModule class that returns an instance of the CustomLoggerModule class, a class that implements Nest's LoggerService interface.
I now want to have access to the Logger inside the AppModule and this is what I've tried:
#Module({
imports: [
ConfigModule.forRoot(),
ESModule,
ElasticSearchConfigModule,
KafkaConfigModule,
IndexModule,
AppConfigModule,
ReadyModule,
],
providers: [
{
provide: APP_FILTER, //you have to use this custom provider
useClass: ErrorFilter, //this is your custom exception filter
},
Logger,
],
})
export class AppModule implements NestModule {
constructor(private moduleRef: ModuleRef) {}
configure(consumer: MiddlewareConsumer) {
const logger = this.moduleRef.get(Logger) as CustomLoggerModule;
const logger.initMiddleware(consumer);
}
}
But in this way, I get an exception at the line logger.initMiddleware, because the logger returned by moduleRef is of type Logger
Obviously by trying to access CustomLogger inside modules other than the AppModule by dependency injection works as expected
How can i access my custom logger instance inside the appModule ?

Answer 1

From Nest: "Because application instantiation (NestFactory.create()) happens outside the context of any module, it doesn't participate in the normal Dependency Injection phase of initialization."
So, you must ensure that at least one application module imports a CustomloggerModule to trigger Nest to instantiate a singleton instance of the custom logger class.
One of your application modules needs to have the following:
providers: [Logger]
exports: [Logger]
Also, your not setting the value of the optional logger property in NestFactory.create() to an object that fulfills the LoggerService interface. Try:
{
logger: logger
}
Then, you need to instruct Nest to use the logger singleton instance in your bootstrap:
const app = await NestFactory.create(AppModule, {
logger,
});
app.useLogger(logger);