Testing

Testing Utilities

Import from @nestarc/tenancy/testing:

import { TestTenancyModule, withTenant, expectTenantIsolation } from '@nestarc/tenancy/testing';

// 1. Use TestTenancyModule in unit/integration tests (no middleware or guard)
const module = await Test.createTestingModule({
  imports: [TestTenancyModule.register()],
  providers: [MyService],
}).compile();

// 2. Run code in a tenant context
const result = await withTenant('tenant-1', () => service.findAll());

// 3. Assert tenant isolation in E2E tests
await expectTenantIsolation(prisma.user, 'tenant-a-uuid', 'tenant-b-uuid');

Event System

Optional integration with @nestjs/event-emitter. Install the package and import EventEmitterModule:

import { EventEmitterModule } from '@nestjs/event-emitter';
import { TenancyEvents } from '@nestarc/tenancy';

@Module({
  imports: [
    EventEmitterModule.forRoot(),
    TenancyModule.forRoot({ tenantExtractor: 'x-tenant-id' }),
  ],
})
export class AppModule {}

// Listen for events anywhere in your app
@Injectable()
class TenantLogger {
  @OnEvent(TenancyEvents.RESOLVED)
  handleResolved({ tenantId }: { tenantId: string }) {
    console.log(`Tenant resolved: ${tenantId}`);
  }
}

Events: tenant.resolved, tenant.not_found, tenant.validation_failed, tenant.context_bypassed, tenant.cross_check_failed.

If @nestjs/event-emitter is not installed, events are silently skipped — no errors.

OpenTelemetry

Optional integration with @opentelemetry/api. Install the package to enable automatic tenant context in traces:

npm install @opentelemetry/api

TenancyModule.forRoot({
  tenantExtractor: 'X-Tenant-Id',
  telemetry: {
    spanAttributeKey: 'tenant.id', // default
    createSpans: true,              // create custom spans for tenant lifecycle
  },
})

When enabled, tenant.id is automatically added as a span attribute to the active span on every request. If createSpans is true, a tenant.resolved span is also created.

If @opentelemetry/api is not installed, telemetry is silently skipped — no errors.