Error Tracking Overview
Set up comprehensive error tracking with Sentry to automatically capture, report, and analyze exceptions, performance issues, and application stability.
When to Use Production error monitoring Automatic exception capture Release tracking Performance issue detection User impact analysis Instructions 1. Sentry Setup npm install -g @sentry/cli npm install @sentry/node @sentry/tracing sentry init -d
- Node.js Sentry Integration // sentry.js const Sentry = require("@sentry/node"); const Tracing = require("@sentry/tracing");
Sentry.init({ dsn: process.env.SENTRY_DSN, environment: process.env.NODE_ENV || 'development', tracesSampleRate: process.env.NODE_ENV === 'production' ? 0.1 : 1.0, release: process.env.APP_VERSION || '1.0.0', integrations: [ new Sentry.Integrations.Http({ tracing: true }), new Tracing.Integrations.Express({ app: true, request: true, transaction: true }) ], ignoreErrors: [ 'Network request failed', 'TimeoutError' ] });
module.exports = Sentry;
- Express Middleware Integration // app.js const express = require('express'); const Sentry = require('./sentry');
const app = express();
app.use(Sentry.Handlers.requestHandler()); app.use(Sentry.Handlers.tracingHandler());
app.get('/api/users/:id', (req, res) => { const transaction = Sentry.startTransaction({ name: 'get_user', op: 'http.server' });
try { const userId = req.params.id;
Sentry.captureMessage('Fetching user', {
level: 'info',
tags: { userId: userId }
});
const user = db.query(`SELECT * FROM users WHERE id = ${userId}`);
if (!user) {
Sentry.captureException(new Error('User not found'), {
level: 'warning',
contexts: { request: { userId } }
});
return res.status(404).json({ error: 'User not found' });
}
transaction.setTag('user.id', user.id);
res.json(user);
} catch (error) { Sentry.captureException(error, { level: 'error', tags: { endpoint: 'get_user', userId: req.params.id } }); res.status(500).json({ error: 'Internal server error' }); } finally { transaction.finish(); } });
app.use(Sentry.Handlers.errorHandler());
app.listen(3000);
- Python Sentry Integration
sentry_config.py
import sentry_sdk from sentry_sdk.integrations.flask import FlaskIntegration from sentry_sdk.integrations.logging import LoggingIntegration import logging import os
sentry_logging = LoggingIntegration( level=logging.INFO, event_level=logging.ERROR )
sentry_sdk.init( dsn=os.environ.get('SENTRY_DSN'), integrations=[FlaskIntegration(), sentry_logging], environment=os.environ.get('ENVIRONMENT', 'development'), release=os.environ.get('APP_VERSION', '1.0.0'), traces_sample_rate=0.1 if os.environ.get('ENVIRONMENT') == 'production' else 1.0, attach_stacktrace=True )
Flask integration
from flask import Flask import sentry_sdk
app = Flask(name)
@app.route('/api/orders/
order = db.query(f'SELECT * FROM orders WHERE id = {order_id}')
if not order:
sentry_sdk.capture_exception(ValueError('Order not found'))
return {'error': 'Order not found'}, 404
return {'order': order}
except Exception as e:
sentry_sdk.capture_exception(e, {
'tags': { 'endpoint': 'get_order', 'order_id': order_id }
})
return {'error': 'Internal server error'}, 500
- Source Maps and Release Management // webpack.config.js const SentryCliPlugin = require('@sentry/webpack-plugin');
module.exports = { plugins: [ new SentryCliPlugin({ include: './dist', urlPrefix: 'https://example.com/', release: process.env.APP_VERSION || '1.0.0', org: process.env.SENTRY_ORG, project: process.env.SENTRY_PROJECT, authToken: process.env.SENTRY_AUTH_TOKEN }) ] };
- CI/CD Release Creation
!/bin/bash
VERSION=$(cat package.json | grep version | head -1 | awk -F: '{ print $2 }' | sed 's/[",]//g')
Create release
sentry-cli releases -o my-org -p my-project create $VERSION
Upload source maps
sentry-cli releases -o my-org -p my-project files $VERSION upload-sourcemaps ./dist
Finalize release
sentry-cli releases -o my-org -p my-project finalize $VERSION
Deploy
sentry-cli releases -o my-org -p my-project deploys $VERSION new -e production
- Custom Error Context // custom-error-context.js const Sentry = require('@sentry/node');
Sentry.configureScope(scope => { scope.setUser({ id: userId, email: userEmail, subscription: 'pro' });
scope.setTag('feature_flag', 'new-ui'); scope.setTag('database', 'postgres-v12');
scope.setContext('character', { name: 'Mighty Fighter', level: 19 });
scope.addBreadcrumb({ category: 'ui.click', message: 'User clicked signup button', level: 'info' });
scope.addBreadcrumb({ category: 'database', message: 'Query executed', level: 'debug', data: { query: 'SELECT * FROM users', duration: 125 } }); });
// Before sending Sentry.init({ dsn: process.env.SENTRY_DSN, beforeSend(event, hint) { if (event.request) { delete event.request.cookies; delete event.request.headers['authorization']; } return event; } });
- Performance Monitoring // performance.js const Sentry = require('@sentry/node');
const transaction = Sentry.startTransaction({ name: 'process_order', op: 'task', data: { orderId: '12345' } });
const dbSpan = transaction.startChild({ op: 'db', description: 'Save order to database' }); saveOrderToDb(order); dbSpan.finish();
const paymentSpan = transaction.startChild({ op: 'http.client', description: 'Process payment' }); processPayment(order); paymentSpan.finish();
transaction.setStatus('ok'); transaction.finish();
Best Practices ✅ DO Set up source maps for production Configure appropriate sample rates Track releases and deployments Filter sensitive information Add meaningful context to errors Use breadcrumbs for debugging Set user information Review error patterns regularly ❌ DON'T Send 100% of errors in production Include passwords in context Ignore configuration for environment Skip source map uploads Log personally identifiable information Use without proper filtering Disable tracking in production Key Commands sentry-cli releases create $VERSION sentry-cli releases files upload-sourcemaps $VERSION ./dist sentry-cli releases deploys $VERSION new -e production sentry-cli releases finalize $VERSION sentry-cli releases info $VERSION