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User Identification

Link errors to specific users to understand who is affected.

Identifying Users​

After a user logs in:

Syntropy.identify({
  id: 'user-123',           // Required: unique user ID
  email: 'user@example.com', // Optional
  name: 'John Doe',          // Optional
  
  // Custom properties
  plan: 'pro',
  company: 'Acme Inc',
});

Clearing User Data​

On logout:

Syntropy.reset();

This clears:

  • User identification
  • Session data
  • Global tags and extras

User Context in Errors​

When an error occurs, user data is attached:

{
  "type": "error",
  "payload": {
    "message": "Cannot read property 'id' of undefined"
  },
  "user": {
    "id": "user-123",
    "email": "user@example.com",
    "name": "John Doe",
    "plan": "pro"
  }
}

Server-Side Identification​

For server SDKs, identify users per-request:

Express​

app.use((req, res, next) => {
  if (req.user) {
    Syntropy.setUser({
      id: req.user.id,
      email: req.user.email,
    });
  }
  next();
});

Node.js with Async Context​

import { Syntropy, runWithContext } from '@eclosion-tech/syntropy-node';

app.use((req, res, next) => {
  runWithContext(
    { user: req.user },
    () => next()
  );
});

Privacy Considerations​

Don't Send PII You Don't Need​

// Good - just the ID
Syntropy.identify({ id: 'user-123' });

// Avoid if not needed
Syntropy.identify({
  id: 'user-123',
  ssn: '123-45-6789', // Don't do this!
  creditCard: '...', // Don't do this!
});

Scrub Sensitive Data​

Syntropy.init({
  projectId: 'your-project-id',
  beforeSend: (event) => {
    // Scrub sensitive fields
    if (event.user) {
      delete event.user.ssn;
      delete event.user.creditCard;
    }
    return event;
  },
});

Affected Users​

In the Syntropy dashboard, you can see:

  • How many unique users are affected by an issue
  • Which specific users hit an error
  • Error frequency per user
  • User environment details