Additional CLS Setup

The CLS middleware/guard/interceptor provide some default functionality, but sometimes you might want to store more contextual things in the CLS.

This can be of course done in a custom enhancer bound after, but for this scenario, the options expose a setup function, which will be executed in the enhancer right after the CLS context is set up.

The function receives the ClsService instance, and can be asynchronous.

Middleware

In case of middleware the Request and Response objects are passed as the second and third parameters.

ClsModule.forRoot({
    middleware: {
        mount: true,
        setup: (cls, req: Request, res: Response) => {
            cls.set('TENANT_ID', req.params['tenantId']);
            cls.set('AUTH', { authenticated: false });
        },
    },
});

Enhancers

In a guard or interceptor, the ExecutionContext object is passed as a second parameter.

ClsModule.forRoot({
    interceptor: {
        mount: true,
        setup: (cls, context) => {
            const req = context.switchToHttp().getRequest<Request>();
            cls.set('TENANT_ID', req.params['tenantId']);
            cls.set('AUTH', { authenticated: false });
        },
    },
});

info

The examples assume usage of Express by default. In case of using Fastify, the types of request and response objects are FastifyRequest and FastifyReply, respectively.