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Load Sentry asynchronously only on error

To prevent a performance penalty by loading Sentry even if no errors occur, we wrote a small handler that lazy loads Sentry.

As I need to homeschool kids nowadays, I don't have time to write tests. So as all hell breaks loose I use Sentry so that I at least will be bombarded with JS error reports to keep me sane. But... If for some miraculous reason I didn't make any mistake, you end up with almost 60kb of useless JavaScript. As your local internet plumber I don't want that so I wrote a small handler that lazy loads Sentry only when an error occurs:

if (process.env.NODE_ENV === 'production') {  // trust me, only do it in production
  const captureError = async error => {
    try {
      console.error(error) // Log error to console for clarification
      const Sentry = await import('@sentry/browser')
      Sentry.init({
        dsn: `YOUR_DSN`,
        release: `YOUR_RELEASE`
      })
      Sentry.captureException(error)
    } catch (e) {
      // all fails, reset window.onerror to prevent infinite loop on window.onerror
      console.error('Logging to Sentry failed', e)
      window.onerror = null
    }
  }
  window.onerror = (message, url, line, column, error) => captureError(error)
  window.onunhandledrejection = event => captureError(event.reason)
}

There you go! Happy debugging 🐛

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