Skip to content

typescript.missing_correlation_id

Observability Medium

Detects HTTP handlers without correlation ID propagation for distributed tracing.

Why It Matters

Missing correlation IDs:

Break tracing — Can’t follow requests across services
Hinder debugging — No way to correlate logs
Increase MTTR — Slower incident resolution

Example

// ❌ Before (no correlation ID)
app.get('/users/:id', async (req, res) => {
  const user = await userService.getUser(req.params.id);
  res.json(user);
});

// ✅ After (with correlation ID)
import { v4 as uuid } from 'uuid';

app.use((req, res, next) => {
  req.correlationId = req.headers['x-correlation-id'] as string || uuid();
  res.setHeader('x-correlation-id', req.correlationId);
  next();
});

app.get('/users/:id', async (req, res) => {
  const user = await userService.getUser(req.params.id, {
    correlationId: req.correlationId,
  });
  res.json(user);
});

What Unfault Detects

Handlers without correlation ID extraction
Missing correlation ID header forwarding
Logs without correlation context