Capturing React Errors Globally

title_thumbnail(Capturing React Errors Globally)

Table of Contents

If you’re new to React and looking to capture all uncaught and unexpected errors or warnings, you’ve come to the right place. In this blog post, we’ll explore how to enable global error handling in React and log the errors to an external API. This approach will save you from having to write error-handling code repeatedly.

Using Try-Catch: Limitations and Alternatives

One common way to handle errors in JavaScript is by using try-catch blocks. While this method works for catching JavaScript errors, it does not directly capture React-specific errors. So, we need an alternative approach to handle React errors globally.

Error Boundary Component

In React 16 and above, the recommended way to capture React errors globally is by using an ErrorBoundary component. This component acts as a boundary around your application components, allowing you to catch errors and display fallback UI when an error occurs.

Here’s an example of how you can implement the ErrorBoundary component:


// app.js
const MOUNT_NODE = document.getElementById('app');

const render = (messages) => {
  ReactDOM.render(
    <Provider store={store}>
      <LanguageProvider messages={messages}>
        <ConnectedRouter history={history}>
          <ErrorBoundary>
            <App />
          </ErrorBoundary>
        </ConnectedRouter>
      </LanguageProvider>
    </Provider>,
    MOUNT_NODE
  );
};

// ErrorBoundary component
export default class ErrorBoundary {
  constructor(props) {
    super(props);
    this.state = { hasError: false };
  }

  componentDidCatch(error, info) {
    // Log the error to an external API
    console.error(error);

    // Update the state to display error UI
    this.setState({ hasError: true });
  }

  render() {
    if (this.state.hasError) {
      return (
        <div>
          <p>Oops! Something went wrong.</p>
        </div>
      );
    }

    return this.props.children;
  }
}

Capturing Errors in Async Methods

It is important to note that errors in async methods like componentDidMount won’t be caught by the error boundary. To capture these errors, you can rely on the window.onerror and window.onunhandledrejection events in vanilla JavaScript. These events can be used to capture any unhandled errors, even outside the React component hierarchy.

Here’s an example of how to utilize these events:


// Global error handler using window.onerror
window.onerror = function(message, source, lineno, colno, error) {
  // Log the error to an external API
  console.error(error);
};

// Global promise rejection handler using window.onunhandledrejection
window.onunhandledrejection = function(event) {
  const error = event.reason;
  // Log the error to an external API
  console.error(error);
};

Conclusion

In this blog post, we explored how to capture React errors globally and log them to an external API. By implementing an ErrorBoundary component and utilizing the window.onerror and window.onunhandledrejection events, you can effectively handle errors in your React application. Now, you can save time and effort by enabling error handling globally instead of writing error-handling code repeatedly.

For more in-depth information, you can refer to the React documentation on error handling.

Feel free to reach out if you have any further questions. Happy coding!

reference :

reactjs

Capturing React Errors Globally