metamask-extension/ui/app/hooks/useMetricEvent.js

import { useContext, useCallback } from 'react'
import { MetaMetricsContext } from '../contexts/metametrics'
import { MetaMetricsContext as NewMetaMetricsContext } from '../contexts/metametrics.new'
import { useEqualityCheck } from './useEqualityCheck'

export function useMetricEvent (config = {}, overrides = {}) {
  const metricsEvent = useContext(MetaMetricsContext)
  const trackEvent = useCallback(() => metricsEvent(config, overrides), [config, metricsEvent, overrides])
  return trackEvent
}

/**
   * track a metametrics event using segment
   * e.g metricsEvent({ event: 'Unlocked MetaMask', category: 'Navigation' })
   *
   * @param {object}  config - configuration object for the event to track
   * @param {string}  config.event - event name to track
   * @param {string}  config.category - category to associate event to
   * @param {boolean} [config.isOptIn] - happened during opt in/out workflow
   * @param {object}  [config.properties] - object of custom values to track, snake_case
   * @param {number}  [config.revenue] - amount of currency that event creates in revenue for MetaMask
   * @param {string}  [config.currency] - ISO 4127 format currency for events with revenue, defaults to US dollars
   * @param {number}  [config.value] - Abstract "value" that this event has for MetaMask.
   * @return {() => undefined} function to execute the tracking event
   */
export function useNewMetricEvent (config) {
  const memoizedConfig = useEqualityCheck(config)
  const metricsEvent = useContext(NewMetaMetricsContext)
  return useCallback(() => metricsEvent(memoizedConfig), [metricsEvent, memoizedConfig])
}