将Firebase Cloud Function称为快照的'ForEach'子级

Question

我正在尝试部署Firebase Cloud Function，该功能将文本消息发送给与之关联的收件人，以获得x条文本消息。 当对“发送”实时数据库参考进行更新时，表明用户已按下“发送”按钮，将在我的iOS应用中触发该功能。

我的Firebase结构是

  {
  "user1uid": {
    "send": false
    "messagesToSend": {
      "messageuid1": {
         "messageText": "What's for dinner?",
         "recipientNumber": "+18017378888",
      }
      "messageuid2:
         "messageText": "Who won the Cowboys game?",
         "recipientNumber": "+18017377787",
      }
   }
   "user2uid": {
    "send": false
    "messagesToSend": {
      "messageuid1": {
         "messageText": "What's for dinner?",
         "recipientNumber": "+18017378888",
      }
      "messageuid2:
         "messageText": "Who won the Cowboys game?",
         "recipientNumber": "+18017377787",
      }
   }
}

我的代码当前仅发送一条消息，我不确定如何正确地遍历每个用户的messagesToSend节点并发送其中的所有消息。

我一直在尝试遵循此处的教程。 我查看了以下堆栈溢出响应，但是无法从中解密或得出解决方案：

Firebase云功能承诺
我是否正确使用ForEach？

我的发送一条消息的index.js代码如下：

const functions = require('firebase-functions');

// The Firebase Admin SDK to access the Firebase Realtime Database.
const admin = require('firebase-admin');
admin.initializeApp();

const twilio = require('twilio')

const accountSid = functions.config().twilio.sid;
const authToken  = functions.config().twilio.token;

const client = new twilio(accountSid, authToken);

const twilioNumber = functions.config().twilio.number;


// Start cloud function
exports.sendSecrets = functions.database
       .ref('/{uid}/send')
       .onUpdate((change,context) => {

    const uid = context.params.uid;

    return admin.database().ref(uid+'/messagesToSend').once('value').then(snapshot => {

      snapshot.forEach(function(childSnapshot) {

          var key = childSnapshot.key;
          var messageData = childSnapshot.val();
          **if (messageData.sanitized) return true;**
          var message = messageData.messageText;
          var phoneNumber = messageData.recipientNumber;

          const textMessage = {
            body: `From My App - ${message}`,
            from: twilioNumber, // From Twilio number
            to: phoneNumber  // Text to this number
          }
          return client.messages.create(textMessage)
        })
        **return snapshot.ref.toString();**
    });
}); 

请注意，在两端标记为**的行表示我知道我需要根据收到的错误消息返回某些内容，该错误消息表明“每个then（）应返回值或抛出”。

Answer 1

我假设您正在使用使用twilio-node库： https : twilio-node 。

由于要并行发送多个消息，因此必须使用Promise.all() ，如下所示：

const functions = require('firebase-functions');

// The Firebase Admin SDK to access the Firebase Realtime Database.
const admin = require('firebase-admin');
admin.initializeApp();

const twilio = require('twilio')

const accountSid = functions.config().twilio.sid;
const authToken  = functions.config().twilio.token;

const client = new twilio(accountSid, authToken);

const twilioNumber = functions.config().twilio.number;


// Start cloud function
exports.sendSecrets = functions.database
       .ref('/{uid}/send')
       .onUpdate((change,context) => {

    const uid = context.params.uid;

    return admin.database().ref(uid+'/messagesToSend').once('value')
    .then(snapshot => {

      const promises = [];

      snapshot.forEach(function(childSnapshot) {

          var key = childSnapshot.key;
          var messageData = childSnapshot.val();
          //**if (messageData.sanitized) return true;**
          var message = messageData.messageText;
          var phoneNumber = messageData.recipientNumber;

          const textMessage = {
            body: `From My App - ${message}`,
            from: twilioNumber, // From Twilio number
            to: phoneNumber  // Text to this number
          }

          promises.push(client.messages.create(textMessage));
      })

      return Promise.all(promises);
    })
    // Edits made below to parentheses/brackets
    .then(results => {
      //Do whatever you want !!
      // e.g. print the results which will be an array of messages
      // (see https://www.twilio.com/docs/libraries/node#testing-your-installation)
    })            
}); 

您还可以简单地返回Promise.all() ，如下所示：

....
     return Promise.all(promises);
   })
});