sentry.js

import * as Sentry from '@sentry/browser'
import { Integrations } from '@sentry/tracing'

if (process.env.SENTRY_DSN) {
  Sentry.init({
    dsn: process.env.SENTRY_DSN,
    integrations: [new Integrations.BrowserTracing()],

    // Set tracesSampleRate to 1.0 to capture 100%
    // of transactions for performance monitoring.
    // We recommend adjusting this value in production
    tracesSampleRate: 1.0,
  })
} else {
  console.log('Sentry is turned off.')
}

export function captureMessage(message, data) {
  // Sentry doesn't provide the option of seeing the full message if it's long
  // and Elm decode errors that log the entire data structure are very long
  // and have the useful bit at the very end, which is truncated by Sentry
  const truncatedData =
    data.length < 2000
      ? data
      : data.slice(0, 1000) + '\n...TRUNCATED...\n' + data.slice(-1000)

  if (process.env.SENTRY_DSN) {
    console.log('The following information has been reported:')
    console.log(truncatedData)

    Sentry.captureEvent({
      message,
      breadcrumbs: [
        {
          message: truncatedData,
        },
      ],
    })
  } else {
    console.log(
      'Error reporting is currently turned off. Here is what would have been reported:',
    )
    console.log(truncatedData)
  }
}