Error Tracking Integrator

3. Install and Configure

Sentry (React example):

npm install @sentry/react

import * as Sentry from "@sentry/react";

Sentry.init({
  dsn: process.env.REACT_APP_SENTRY_DSN,
  environment: process.env.NODE_ENV,
  tracesSampleRate: 1.0,
  integrations: [
    new Sentry.BrowserTracing(),
    new Sentry.Replay()
  ],
});

Sentry (Node.js/Express):

const Sentry = require("@sentry/node");

Sentry.init({
  dsn: process.env.SENTRY_DSN,
  environment: process.env.NODE_ENV,
  tracesSampleRate: 1.0,
});

// Request handler (first middleware)
app.use(Sentry.Handlers.requestHandler());

// Error handler (after all routes, before error middleware)
app.use(Sentry.Handlers.errorHandler());

4. Add Error Boundaries (React)

import { ErrorBoundary } from '@sentry/react';

function App() {
  return (
    <ErrorBoundary fallback={<ErrorFallback />}>
      <YourApp />
    </ErrorBoundary>
  );
}

5. Add Context

User context:

Sentry.setUser({
  id: user.id,
  email: user.email,
  username: user.username
});

Tags:

Sentry.setTag("page_locale", "en-US");
Sentry.setTag("feature_flag", "new_ui");

Context:

Sentry.setContext("order", {
  id: order.id,
  total: order.total,
  items: order.items.length
});

6. Breadcrumbs

Track user actions leading to error:

Sentry.addBreadcrumb({
  category: "auth",
  message: "User logged in",
  level: "info"
});

Sentry.addBreadcrumb({
  category: "ui",
  message: "Button clicked",
  data: { buttonId: "submit-form" }
});

7. Manual Error Capture

try {
  riskyOperation();
} catch (error) {
  Sentry.captureException(error, {
    tags: { section: "payment" },
    level: "error",
    extra: { orderId: order.id }
  });
}

8. Filter Sensitive Data

Scrub PII:

Sentry.init({
  beforeSend(event, hint) {
    // Don't send if contains sensitive data
    if (event.request?.data?.password) {
      delete event.request.data.password;
    }
    return event;
  },
  ignoreErrors: [
    // Ignore browser extension errors
    /extensions\//i,
    /^Non-Error promise rejection/,
  ]
});

9. Source Maps (Production)

Enable source maps for readable stack traces:

Webpack:

// webpack.config.js
module.exports = {
  devtool: 'source-map',
  plugins: [
    new SentryWebpackPlugin({
      org: "your-org",
      project: "your-project",
      authToken: process.env.SENTRY_AUTH_TOKEN,
      include: "./dist",
    }),
  ],
};

10. Alert Configuration

Set up alerts for:

• New issues
• Regression (resolved issue occurs again)
• Spike in error rate
• Critical errors (payment, auth failures)

11. Performance Monitoring

Add transaction tracking:

const transaction = Sentry.startTransaction({
  name: "processOrder",
  op: "task"
});

try {
  await processOrder();
} finally {
  transaction.finish();
}

12. Best Practices

• Environment separation: Different projects for dev/staging/prod
• Release tracking: Tag errors with release version
• Sample rates: 100% errors, lower% for performance
• Team notifications: Slack/email integration
• Issue assignment: Auto-assign to code owners
• Error grouping: Custom fingerprinting for better grouping
• Don't log sensitive data: PII, passwords, tokens

Supporting Files

• templates/sentry-react.js: React integration template
• templates/sentry-node.js: Node.js integration template
• templates/sentry-python.py: Python integration template