Wait for Firebase emulators to finish

logListener.ts

import { client as Client, connection as Connection } from 'websocket'

export interface LogMessage {
  type: string
  utf8Data: string
}
export interface LogMessageContent {
  level: string
  data: Data
  timestamp: number
  message: string
}

export interface Data {
  metadata: Metadata
}

export interface Metadata {
  emulator: Emulator
  function: Emulator
  message: string
}

export interface Emulator {
  name: string
}

let con: Connection
const listeners: (() => void)[] = []

export function initFirebaseListener(waitTimeMs: number = 100) {
  return new Promise((resolve) => {
    if (con) {
      resolve(true)
    }
    const socket = new Client()
    socket.connect('ws://localhost:4500/')
    socket.on('connect', (connection) => {
      con = connection
      let debounce: NodeJS.Timeout
      con.on('message', (message) => {
        const data = message as any as LogMessage
        const messageContent = JSON.parse(data.utf8Data) as LogMessageContent
        if (messageContent.message.startsWith('Beginning execution of "')) {
          if (debounce) {
            clearTimeout(debounce)
          }
        } else if (messageContent.message.startsWith('Finished "')) {
          debounce = setTimeout(
            () => listeners.forEach((listener) => listener()),
            waitTimeMs
          )
        }
      })
      resolve(true)
    })
  })
}

export function closeSocket() {
  con.close()
}

export function waitForFirebaseToFinish() {
  return new Promise((resolve) => {
    listeners.push(() => resolve(true))
  })
}