NestJS

AllStak SDK for NestJS. Adds a global interceptor and exception filter for request telemetry, errors, spans, and trace propagation.

Install

npm install @allstak/nestjs

Peer dependencies:

npm install @nestjs/common @nestjs/core reflect-metadata rxjs

Setup

import { Module } from '@nestjs/common';
import { AllStakModule } from '@allstak/nestjs';

@Module({
  imports: [
    AllStakModule.forRoot({
      apiKey: process.env.ALLSTAK_API_KEY,
      environment: process.env.NODE_ENV ?? 'production',
      release: process.env.ALLSTAK_RELEASE,
      serviceName: 'api',
      captureRequestHeaders: true,
    }),
  ],
})
export class AppModule {}

Async config

AllStakModule.forRootAsync({
  useFactory: () => ({
    apiKey: process.env.ALLSTAK_API_KEY,
    environment: process.env.NODE_ENV ?? 'production',
    release: process.env.ALLSTAK_RELEASE,
    serviceName: 'api',
  }),
});

What is captured

• Inbound HTTP request telemetry.
• Outbound HTTP request telemetry (global fetch, plus optional @nestjs/axios).
• Unhandled exceptions with stack traces.
• Process-level fatal errors (uncaught exceptions / unhandled rejections) that escape the request pipeline.
• Database queries (opt-in Prisma / TypeORM instrumentation) with the active trace.
• Server + client spans for each request and downstream call.
• W3C traceparent + baggage propagation on inbound responses AND outbound calls.

Configuration

Release health

AllStakModule.forRoot(...) opens a single release-health session per process on module init (/ingest/v1/sessions/start) and closes it on graceful shutdown (/ingest/v1/sessions/end) with the final status (ok / errored / crashed). Sessions are never sampled and the whole path is fail-open. Call app.enableShutdownHooks() so the closing event fires. Set enableAutoSessionTracking: false to opt out.

Offline queue

When telemetry cannot be delivered (network outage, retry exhausted, or the process shuts down with events still buffered) the SDK persists the already-redacted wire body to a bounded filesystem spool (<os.tmpdir()>/allstak-nestjs-spool by default) instead of dropping it. On the next init it asynchronously drains the spool and re-sends each entry through the normal transport, removing it only once accepted (2xx) or permanently undeliverable (a 4xx other than 429). The spool is bounded by count, total bytes, and max age, evicting the oldest entries first. Session lifecycle calls (/sessions/start, /sessions/end) are live-only and never persisted. If the spool directory is not writable (read-only FS, serverless, edge runtime with no fs) the SDK degrades silently to in-memory — it never throws or blocks init. Set enableOfflineQueue: false to opt out, or offlineQueueDir to point at a durable path.

Outbound HTTP tracing

Distributed traces only stay connected if egress carries the trace context. The SDK wraps the global fetch so every outbound call made while handling a request becomes a child span of that request's trace: it injects W3C traceparent + baggage (continuing the inbound trace id and sampled flag) and emits a http.client span plus an outbound HTTP request row. The SDK's own ingest host is always skipped, and the wrapper is fully fail-open — an instrumentation error never breaks the caller's request. Set enableOutboundHttp: false to opt out.

For @nestjs/axios (an optional/peer integration the SDK never hard-depends on), instrument the HttpService once after the module is registered:

import { Injectable, OnModuleInit } from '@nestjs/common';
import { HttpService } from '@nestjs/axios';
import { instrumentHttpService } from '@allstak/nestjs';

@Injectable()
export class HttpTracing implements OnModuleInit {
  constructor(private readonly http: HttpService) {}
  onModuleInit(): void {
    instrumentHttpService(this.http); // axios requests now propagate the trace
  }
}

Global error handlers

The interceptor and exception filter only see errors that flow through the NestJS request pipeline. A truly unhandled error thrown off that path — in a timer, an event-emitter callback, or a forgotten await — would otherwise terminate the process with nothing captured. On module init the SDK installs process.on('uncaughtException') and process.on('unhandledRejection') so such a failure is captured at fatal level, the release-health session is marked crashed, and buffered telemetry is flushed before exit.

Node's existing behaviour is preserved: for an uncaught exception the SDK re-emits out-of-band only when it is the sole listener (so Node's default crash-and-exit still applies); when your app has its own uncaughtException listener the SDK does not force an exit — your handler owns that decision. Unhandled rejections are captured without changing the process's rejection mode. The whole path is fail-open. Set enableGlobalErrorHandlers: false to opt out.

Database queries (Prisma / TypeORM)

Opt-in ORM instrumentation emits a /ingest/v1/db row for every query — normalized SQL (literal values stripped to ?, so no parameter values leave the process), duration, status, and the active request trace/span ids so a query made while handling a request becomes a child of that request's trace. Prisma and TypeORM are optional/peer integrations the SDK never hard-depends on; you pass your client / data-source in once, mirroring instrumentHttpService().

// Prisma — $extends returns a NEW client, so assign it back.
import { instrumentPrisma } from '@allstak/nestjs';
prisma = instrumentPrisma(prisma);

// TypeORM — attaches a query logger to your DataSource.
import { instrumentDataSource } from '@allstak/nestjs';
instrumentDataSource(dataSource);

Both helpers are idempotent and fail-open. Set enableDbInstrumentation: false to make them no-ops.

Privacy

Sensitive header and metadata keys are redacted before telemetry is sent. Add redactKeys for application-specific fields.

Troubleshooting

• No request events: confirm AllStakModule.forRoot(...) is imported by your root module.
• No errors: confirm no custom exception filter is swallowing exceptions before global filters run.
• Missing correlation: preserve incoming traceparent, baggage, and x-request-id headers at your proxy.

Contributing and Support

• Report bugs with the GitHub bug report template: https://github.com/AllStak/allstak-nestjs/issues/new/choose
• Open pull requests using the checklist in CONTRIBUTING.md.
• Report security vulnerabilities privately through SECURITY.md.

License

MIT