Frontend Data Error Handling

Frontend Data Error Handling

When to use this skill

• Handling API errors
• Showing error messages
• Implementing retry logic
• Error boundaries

Workflow

• Catch errors at API layer
• Show user-friendly messages
• Log errors for debugging
• Implement retry for transient errors
• Use error boundaries for crashes

Instructions

API Error Handling

try {
  const data = await fetchUser(id);
  return data;
} catch (error) {
  if (error.response?.status === 404) {
    throw new NotFoundError('User not found');
  }
  if (error.response?.status >= 500) {
    throw new ServerError('Server error, please try again');
  }
  throw error;
}

React Error Boundary

class ErrorBoundary extends React.Component {
  state = { hasError: false, error: null };

  static getDerivedStateFromError(error) {
    return { hasError: true, error };
  }

  componentDidCatch(error, errorInfo) {
    console.error('Error:', error, errorInfo);
  }

  render() {
    if (this.state.hasError) {
      return <ErrorFallback error={this.state.error} />;
    }
    return this.props.children;
  }
}

Resources

• Show friendly messages to users
• Log detailed errors for debugging
• Retry transient failures