@sentry/browser

What is @sentry/browser?

The @sentry/browser package is a JavaScript SDK for Sentry, which is an error tracking service that helps developers monitor and fix crashes in real time. The SDK hooks into the global error handling mechanisms of the browser and captures unhandled exceptions and other errors, providing rich context and insights into the underlying issues.

What are @sentry/browser's main functionalities?

Error Tracking

This feature automatically captures JavaScript exceptions and sends them to Sentry for analysis and tracking. The code initializes Sentry with a DSN (Data Source Name) and sets up a global error handler to capture exceptions.

Sentry.init({ dsn: 'YOUR_DSN' });

window.onerror = function (errorMsg, url, lineNumber, column, errorObj) {
  Sentry.captureException(errorObj);
  return false;
}

Manual Error Reporting

This allows developers to manually report exceptions or errors to Sentry. The code block demonstrates how to catch an error in a try-catch block and manually send it to Sentry using the captureException method.

Sentry.init({ dsn: 'YOUR_DSN' });

try {
  // Code that might fail
} catch (error) {
  Sentry.captureException(error);
}

Performance Monitoring

This feature enables performance monitoring by capturing transactions and spans. The code initializes Sentry with a sample rate for transactions and demonstrates how to start and finish a transaction, which can be used to measure the performance of operations.

Sentry.init({ dsn: 'YOUR_DSN', tracesSampleRate: 1.0 });

const transaction = Sentry.startTransaction({ name: 'test transaction' });
// ... some code ...
transaction.finish();

Breadcrumbs

Breadcrumbs are a trail of events that happened prior to an issue. This feature allows you to record breadcrumbs manually. The code shows how to add a breadcrumb for an authentication event.

Sentry.init({ dsn: 'YOUR_DSN' });

Sentry.addBreadcrumb({
  category: 'auth',
  message: 'User authenticated',
  level: Sentry.Severity.Info
});

User Feedback

This feature allows you to collect user feedback when an error occurs. The code initializes Sentry and then shows a dialog to the user to collect feedback for a specific event.

Sentry.init({ dsn: 'YOUR_DSN' });

Sentry.showReportDialog({ eventId: 'event_id' });

Other packages similar to @sentry/browser

bugsnag-js

Bugsnag provides similar error tracking and monitoring capabilities as Sentry. It offers real-time error reporting and can be used to monitor application stability. Bugsnag also provides features for error diagnostics and supports multiple platforms.

raygun4js

Raygun is another error monitoring service that offers crash reporting with detailed diagnostics. It supports real-time error tracking and performance monitoring, and it can be used to identify and diagnose software errors and performance issues.

rollbar-browser

Rollbar offers real-time error tracking and is similar to Sentry in its capabilities. It includes features like telemetry, person tracking, and version tracking. Rollbar provides a comprehensive dashboard for monitoring and analyzing errors.

README

Official Sentry SDK for Browsers

Links

• Official SDK Docs

Usage

To use this SDK, call Sentry.init(options) as early as possible after loading the page. This will initialize the SDK and hook into the environment. Note that you can turn off almost all side effects using the respective options.

import * as Sentry from '@sentry/browser';

Sentry.init({
  dsn: '__DSN__',
  // ...
});

To set context information or send manual events, use the exported functions of @sentry/browser. Note that these functions will not perform any action before you have called Sentry.init():

import * as Sentry from '@sentry/browser';

// Set user information, as well as tags and further extras
Sentry.setExtra('battery', 0.7);
Sentry.setTag('user_mode', 'admin');
Sentry.setUser({ id: '4711' });

// Add a breadcrumb for future events
Sentry.addBreadcrumb({
  message: 'My Breadcrumb',
  // ...
});

// Capture exceptions, messages or manual events
Sentry.captureMessage('Hello, world!');
Sentry.captureException(new Error('Good bye'));
Sentry.captureEvent({
  message: 'Manual',
  stacktrace: [
    // ...
  ],
});

Changelog

9.10.0

Important Changes

• feat: Add support for logs

  • feat(node): Add logging public APIs to Node SDKs (#15764)
  • feat(core): Add support for beforeSendLog (#15814)
  • feat(core): Add support for parameterizing logs (#15812)
  • fix: Remove critical log severity level (#15824)

  All JavaScript SDKs other than @sentry/cloudflare and @sentry/deno now support sending logs via dedicated methods as part of Sentry's upcoming logging product.

  Logging is gated by an experimental option, _experiments.enableLogs.

  Sentry.init({
    dsn: 'PUBLIC_DSN',
    // `enableLogs` must be set to true to use the logging features
    _experiments: { enableLogs: true },
  });
  
  const { trace, debug, info, warn, error, fatal, fmt } = Sentry.logger;
  
  trace('Starting database connection', { database: 'users' });
  debug('Cache miss for user', { userId: 123 });
  error('Failed to process payment', { orderId: 'order_123', amount: 99.99 });
  fatal('Database connection pool exhausted', { database: 'users', activeConnections: 100 });
  
  // Structured logging via the `fmt` helper function. When you use `fmt`, the string template and parameters are sent separately so they can be queried independently in Sentry.
  
  info(fmt(`Updated profile for user ${userId}`));
  warn(fmt(`Rate limit approaching for endpoint ${endpoint}. Requests: ${requests}, Limit: ${limit}`));
  

  With server-side SDKs like @sentry/node, @sentry/bun or server-side of @sentry/nextjs or @sentry/sveltekit, you can do structured logging without needing the fmt helper function.

  const { info, warn } = Sentry.logger;
  
  info('User %s logged in successfully', [123]);
  warn('Failed to load user %s data', [123], { errorCode: 404 });
  

  To filter logs, or update them before they are sent to Sentry, you can use the _experiments.beforeSendLog option.

• feat(browser): Add diagnoseSdkConnectivity() function to programmatically detect possible connectivity issues (#15821)

  The diagnoseSdkConnectivity() function can be used to programmatically detect possible connectivity issues with the Sentry SDK.

  const result = await Sentry.diagnoseSdkConnectivity();
  

  The result will be an object with the following properties:

  • "no-client-active": There was no active client when the function was called. This possibly means that the SDK was not initialized yet.
  • "sentry-unreachable": The Sentry SaaS servers were not reachable. This likely means that there is an ad blocker active on the page or that there are other connection issues.
  • undefined: The SDK is working as expected.

• SDK Tracing Performance Improvements for Node SDKs

  • feat: Stop using dropUndefinedKeys (#15796)
  • feat(node): Only add span listeners for instrumentation when used (#15802)
  • ref: Avoid dropUndefinedKeys for spanToJSON calls (#15792)
  • ref: Avoid using SentryError for PromiseBuffer control flow (#15822)
  • ref: Stop using dropUndefinedKeys in SpanExporter (#15794)
  • ref(core): Avoid using SentryError for event processing control flow (#15823)
  • ref(node): Avoid dropUndefinedKeys in Node SDK init (#15797)
  • ref(opentelemetry): Avoid sampling work for non-root spans (#15820)

  We've been hard at work making performance improvements to the Sentry Node SDKs (@sentry/node, @sentry/aws-serverless, @sentry/nestjs, etc.). We've seen that upgrading from 9.7.0 to 9.10.0 leads to 30-40% improvement in request latency for HTTP web-server applications that use tracing with high sample rates. Non web-server applications and non-tracing applications will see smaller improvements.

Other Changes

• chore(deps): Bump rrweb to 2.35.0 (#15825)
• deps: Bump bundler plugins to 3.2.3 (#15829)
• feat: Always truncate stored breadcrumb messages to 2kb (#15819)
• feat(nextjs): Disable server webpack-handling for static builds (#15751)
• fix(nuxt): Don't override Nuxt options if undefined (#15795)