observability-hooks-js Package

Available Hooks

BaseLogHook Batching Pattern

All platform hooks extend BaseLogHook which implements automatic batching with configurable flush intervals:

abstract class BaseLogHook<T> extends BaseHook {
  // Accumulates log records in a batch
  // Flushes when: batchSize is reached OR flushInterval expires
  protected async batchFlush(doc: T): Promise<void>;

  // Subclass sends the batch to the platform
  protected abstract sendBatch(docs: T[]): Promise<void>;
}

// Defaults:
// batchSize: 100 documents
// flushInterval: 5000ms (5 seconds)

Splunk Integration

import { SplunkLogHook } from '@edge-stream/observability-hooks-js';

const server = stream.server('bas')!;

server.incomingPipeline.addHook(new SplunkLogHook({
  hecUrl: 'https://splunk.company.com:8088/services/collector',
  hecToken: process.env.SPLUNK_HEC_TOKEN!,
  sourcetype: 'edgestream:pipeline',
  batchSize: 100,
  flushInterval: 5000,   // flush at least every 5 seconds
}));

Datadog Integration

import { DatadogHook } from '@edge-stream/observability-hooks-js';

server.incomingPipeline.addHook(new DatadogHook({
  apiKey: process.env.DATADOG_API_KEY!,
  site: 'datadoghq.com',   // or 'datadoghq.eu', 'us3.datadoghq.com', etc.
  batchSize: 50,
  flushInterval: 3000,
}));

Generic REST Endpoint (WebMcpHook)

import { WebMcpHook } from '@edge-stream/observability-hooks-js';

// Forward every pipeline event to a custom webhook
server.incomingPipeline.addHook(new WebMcpHook({
  endpoint: 'https://internal-monitoring.company.com/webhook',
  headers: {
    'X-API-Key': process.env.MONITORING_KEY!,
    'Content-Type': 'application/json',
  },
  retries: 3,
}));

HookActivityLogger (from edge-stream-js)

The in-process observability hook — feeds HooksMonitor and SubscribersMonitor. Unlike the external platform hooks, it writes to the local LoggingService ring buffer instead of a remote endpoint:

import { HookActivityLogger } from 'edge-stream-js';
// (also re-exported as LogHook from @edge-stream/observability-hooks-js)

server.incomingPipeline.addHook(new HookActivityLogger()); // priority 5

// Respects LogSettings.isHookLoggingEnabled()
// Use getLogSettings().setHookLoggingEnabled(false) to disable at runtime

Combining Multiple Observability Hooks

// Development: in-process monitor only
if (import.meta.env.DEV) {
  server.incomingPipeline.addHook(new HookActivityLogger()); // local UI monitor
}

// Production: external platform logging
if (import.meta.env.PROD) {
  server.incomingPipeline.addHook(new DatadogHook({
    apiKey: env.DATADOG_KEY,
    site: 'datadoghq.com',
    batchSize: 100,
    flushInterval: 5000,
  }));
}