Using an Interceptor

Another place to initiate the CLS context is an ClsInterceptor, which, unlike the ClsGuard uses AsyncLocalStorage#run method to wrap the following code, which is considered safer than enterWith.

To use it, pass its configuration to the interceptor property to the ClsModule.forRoot() options:

Automatically

app.module.ts

@Module({
    imports: [
        ClsModule.forRoot({
            interceptor: { mount: true },
        }),
    ],
    // ...
})
export class AppModule {}

Manually

Or mount it manually as APP_INTERCEPTOR

app.module.ts

@Module({
    imports: [
        ClsModule.forRoot({
            interceptor: { mount: false }
        }),
    ]
    providers: [
        {
            provide: APP_INTERCEPTOR,
            useClass: ClsInterceptor,
        },
    ],
    // ...
})
export class AppModule {}

or directly on the Controller/Resolver with:

@UseInterceptors(ClsInterceptor);

note

Please note: Since Nest's Interceptors run after Guards, that means using this method makes CLS unavailable in Guards (and in case of REST Controllers, also in Exception Filters).