GitHub - abiglobalhealth/chatfireServerless: A serverless chat backend - built on Firebase Cloud Functions

# use the firebase cli to initialize a project
yarn global add firebase-tools

mkdir example && cd example
firebase init functions

# add chatFireServerless
cd functions
yarn add chatFireServerless

const chatFireServerless = require('chatFireServerless')

const serviceAccount = require('./serviceAccount.json') // temporarily required
// You'll also need to download your serviceAccount file from google.
// This is because default credentials dont allow you to call `createCustomToken`.
// more here: https://stackoverflow.com/questions/42717540/firebase-cloud-functions-createcustomtoken

module.exports = chatFireServerless({
  serviceAccount, //temporarily required
  authenticate: payload => {
  //  do your authentication/authorization and return the users id. For example:
  //  return fetch('https://api.mybackend.com', payload)
  //    .then(user => ({ uid: user.id }))
  })
})

{
  "rules": {
    "messages": {
      "$roomId": {
        ".indexOn": [ "at" ], // index messages by timestamp
        ".read": true, // anyone can read messages from any chatroom
        "$messageId": {
          ".write": "!data.exists() && newData.exists()" // users can only write new messages, not modify existing messages
        },
      },
    },
    "chats": {
      ".indexOn": [ "at" ], // index on the timestamp of the last message in each room
      ".read": true, // anyone can read the list of chatrooms
      ".write" false // only the server can write here
    }
  }
}