metamask-extension/ui/app/contexts/metametrics.js

import React, {
  Component,
  createContext,
  useEffect,
  useCallback,
  useState,
  useMemo,
} from 'react'
import { useSelector } from 'react-redux'
import PropTypes from 'prop-types'
import { useHistory } from 'react-router-dom'
import { captureException } from '@sentry/browser'

import {
  getCurrentNetworkId,
  getAccountType,
  getNumberOfAccounts,
  getNumberOfTokens,
  getCurrentChainId,
} from '../selectors/selectors'
import { getSendToken } from '../selectors/send'
import { txDataSelector } from '../selectors/confirm-transaction'
import { getEnvironmentType } from '../../../app/scripts/lib/util'
import { getTrackMetaMetricsEvent } from '../../../shared/modules/metametrics'
import { getCurrentLocale } from '../ducks/metamask/metamask'

export const MetaMetricsContext = createContext(() => {
  captureException(
    Error(
      `MetaMetrics context function was called from a react node that is not a descendant of a MetaMetrics context provider`,
    ),
  )
})

export function MetaMetricsProvider({ children }) {
  const txData = useSelector(txDataSelector) || {}
  const network = useSelector(getCurrentNetworkId)
  const environmentType = getEnvironmentType()
  const chainId = useSelector(getCurrentChainId)
  const locale = useSelector(getCurrentLocale)
  const activeCurrency = useSelector(getSendToken)?.symbol
  const accountType = useSelector(getAccountType)
  const confirmTransactionOrigin = txData.origin
  const metaMetricsId = useSelector((state) => state.metamask.metaMetricsId)
  const participateInMetaMetrics = useSelector(
    (state) => state.metamask.participateInMetaMetrics,
  )
  const metaMetricsSendCount = useSelector(
    (state) => state.metamask.metaMetricsSendCount,
  )
  const numberOfTokens = useSelector(getNumberOfTokens)
  const numberOfAccounts = useSelector(getNumberOfAccounts)
  const history = useHistory()
  const [state, setState] = useState(() => ({
    currentPath: new URL(window.location.href).pathname,
    previousPath: '',
  }))

  const { currentPath } = state

  useEffect(() => {
    const unlisten = history.listen(() =>
      setState((prevState) => ({
        currentPath: new URL(window.location.href).pathname,
        previousPath: prevState.currentPath,
      })),
    )
    // remove this listener if the component is no longer mounted
    return unlisten
  }, [history])

  /**
   * track a metametrics event
   *
   * @param {import('../../../shared/modules/metametrics').MetaMetricsEventPayload} - payload for event
   * @returns undefined
   */
  const trackEvent = useMemo(() => {
    const referrer = confirmTransactionOrigin
      ? { url: confirmTransactionOrigin }
      : undefined
    const page = {
      path: currentPath,
    }
    return getTrackMetaMetricsEvent(global.platform.getVersion(), () => ({
      context: {
        referrer,
        page,
      },
      environmentType,
      locale: locale.replace('_', '-'),
      network,
      chainId,
      participateInMetaMetrics,
      metaMetricsId,
      metaMetricsSendCount,
    }))
  }, [
    network,
    chainId,
    locale,
    environmentType,
    participateInMetaMetrics,
    currentPath,
    confirmTransactionOrigin,
    metaMetricsId,
    metaMetricsSendCount,
  ])

  const metricsEvent = useCallback(
    (config = {}, overrides = {}) => {
      const { eventOpts = {} } = config

      return trackEvent({
        event: eventOpts.name,
        category: eventOpts.category,
        isOptIn: config.isOptIn,
        excludeMetaMetricsId:
          eventOpts.excludeMetaMetricsId ??
          overrides.excludeMetaMetricsId ??
          false,
        metaMetricsId: config.metaMetricsId,
        matomoEvent: true,
        properties: {
          action: eventOpts.action,
          number_of_tokens: numberOfTokens,
          number_of_accounts: numberOfAccounts,
          active_currency: activeCurrency,
          account_type: accountType,
          is_new_visit: config.is_new_visit,
          // the properties coming from this key will not match our standards for
          // snake_case on properties, and they may be redundant and/or not in the
          // proper location (origin not as a referrer, for example). This is a temporary
          // solution to not lose data, and the entire event system will be reworked in
          // forthcoming PRs to deprecate the old Matomo events in favor of the new schema.
          ...config.customVariables,
        },
      })
    },
    [accountType, activeCurrency, numberOfTokens, numberOfAccounts, trackEvent],
  )

  return (
    <MetaMetricsContext.Provider value={metricsEvent}>
      {children}
    </MetaMetricsContext.Provider>
  )
}

MetaMetricsProvider.propTypes = { children: PropTypes.node }

export class LegacyMetaMetricsProvider extends Component {
  static propTypes = {
    children: PropTypes.node,
  }

  static defaultProps = {
    children: undefined,
  }

  static contextType = MetaMetricsContext

  static childContextTypes = {
    metricsEvent: PropTypes.func,
  }

  getChildContext() {
    return {
      metricsEvent: this.context,
    }
  }

  render() {
    return this.props.children
  }
}