Setting Custom Context for Requests for Nodejs

Overview

The Hud SDK supports attaching custom context metadata to the forensics data on a current request or event being processed, whether it’s an HTTP request, a message from SQS, or any other handler. This context will be recorded and visible if the endpoint of queue fails or behaves unexpectedly, enabling richer debugging and investigation.

Use setContext() to inject metadata that is relevant to the current execution, such as clientId, messageId, userTier, or featureFlagStatus. The context is scoped to the current execution only, and is automatically cleared afterward.

When to Use

Use setContext if:

• You want extra identifiers in logs or error dashboards for specific requests or messages.
• You need metadata to trace failures or abnormal behaviors across systems (e.g. SQS).
• You want to correlate issues with tenants, plans, user types, or feature rollout states.

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Important Notes

• setContext must be called during the active handling of a request or message.
• It is per-invocation only. Calling it outside a request/message handler (e.g. in startup code) will have no effect.
• The context is automatically cleared after the handler completes.
• Keys are of type string
• Values are of the types: string | number | boolean | string[] | number[]

Example #1: Simple HTTP Handler

import { setContext } from 'hud-sdk/api';

export async function handleRequestOrMessage(request: any) {
  // Set context for the current execution
  setContext({
    clientId: request.clientId,
    requestId: request.id,
  });

  // Your actual logic here
  console.log('Processing request:', request);
}

Example #2: NestJS HTTP Interceptor

import { setContext } from 'hud-sdk/api';
import {
  Injectable,
  NestInterceptor,
  ExecutionContext,
  CallHandler,
} from '@nestjs/common';
import { Observable, tap } from 'rxjs';

@Injectable()
export class LoggingInterceptor implements NestInterceptor {
  intercept(context: ExecutionContext, next: CallHandler): Observable<any> {
    // Example dynamic context
    setContext({
      clientId: 'test',
      other: 2,
    });

    const now = Date.now();
    return next.handle().pipe(
      tap(() => console.log(`Request took ${Date.now() - now}ms`))
    );
  }
}