這邊我們重新打開googleHomeTrigger的function專案，利用node js加入 pub/sub的client端。

npm install @google-cloud/pubsub

新增config.ts

export const pubsubConfig = {
    projectId : 'your-project',
    topicName : 'your-topicName'
}

而在index.ts新增

const {PubSub} = require('@google-cloud/pubsub');

import { pubsubConfig } from './config'

const pubsub = new PubSub(pubsubConfig.projectId);

這邊則是主要進行判斷的部分，依據我的專案情況推播訊息

    exports.googleHomeTrigger = functions.firestore.document('personal-accounts/{firebaseId}/peoples/{tagMac}')
        .onUpdate(async (change, context) => {
        const beforeData = change.before.data() as peopleInterface
        const afterData = change.after.data() as peopleInterface

        const physiologicalState = verifyPhysiologicalState(beforeData, afterData)
        await notifyPhysiological(physiologicalState, afterData)
    .catch(err =>console.log(err))
    });

以及

    //for object
    const dataBuffer = Buffer.from(JSON.stringify(notifyMessage));
    //for string
    // const dataBuffer = Buffer.from(notifyMessage);
    const messageId = await pubsub.topic(pubsubConfig.topicName).publish(dataBuffer);
    console.log(`Message: ${messageId} published.`);

• 這邊因為我傳遞的是物件，須利用JSON.stringify，再設定好pubsub.topic(pubsubConfig.topicName)即可進行Pub的動作