@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 (JavaScript)

Usage

To use this SDK, call SentryClient.create(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 { SentryClient } from '@sentry/browser';

SentryClient.create({
  dsn: '__DSN__',
  // ...
});

To set context information or send manual events, use the provided methods on SentryClient. Note that these functions will not perform any action before you have called SentryClient.install():

// Set user information, as well as tags and further extras
SentryClient.setContext({
  extra: { battery: 0.7 },
  tags: { user_mode: 'admin' },
  user: { id: '4711' },
});

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

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

Advanced Usage

If you don't want to use a global static instance of Sentry, you can create one yourself:

import { BrowserFrontend } from '@sentry/browser';

const client = new BrowserFrontend({
  dsn: '__DSN__',
  // ...
});

client.install();
// ...

Note that install() returns a Promise that resolves when the installation has finished. It is not necessary to wait for the installation before adding breadcrumbs, defining context or sending events. However, the return value indicates whether the installation was successful and the environment could be instrumented:

import { BrowserFrontend } from '@sentry/browser';

const client = new BrowserFrontend({
  dsn: '__DSN__',
  // ...
});

const success = await client.install();
if (success) {
  // Will catch global exceptions, record breadcrumbs for DOM events, etc...
} else {
  // Limited instrumentation, but sending events will still work
}