如何在嵌套的 promise Cloud Functions 中限定 Firebase 的范围

Question

我正在尝试从 Firebase 设置一些变量，然后将它们传递给另一个函数。目前，Promise.all 正在正确设置 foo 和 bar，但在 .then 期间抛出错误，因此未在 Firebase 中设置响应。

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

admin.initializeApp(functions.config().firebase);

exports.someFunc = functions.database.ref(`/data`).onWrite(event => {
  const condition = event.data.val()
  if (condition) {
    // Get the data at this location only once, returns a promise, to ensure retrieval of foo and bar
    const foo = event.data.adminRef.child('foo').once('value')
    const bar = event.data.adminRef.child('bar').once('value')

    return Promise.all([foo, bar]).then(results => {
      const foo = results[0].val()
      const bar = results[1].val()

      return someModule.anotherFunction({
        "foo": foo,
        "bar": bar
      }).then(response => {
        // Get an error thrown that Firebase is not defined
        let updates = {}
        updates['/data'] = response
        return firebase.database().ref().update(updates)
      })
    })
  } else {
    console.log('Fail')
  }
});

控制台登录报错如下：

ReferenceError: firebase is not defined
    at someModule.anotherFunction.then.response 
(/user_code/index.js:100:16)
    at process._tickDomainCallback (internal/process/next_tick.js:129:7)

如何限定 return firebase.database().ref().update(updates); 的范围以设置来自 anotherFunction 的响应？

Answer 1

您需要 include the Firebase Admin SDK，通常称为 admin。

如 getting started documentation for functions 中所示和解释：

Import the required modules and initialize

For this sample, your project must import the Cloud Functions and Admin SDK modules using Node require statements. Add lines like the following to your index.js file:
const functions = require('firebase-functions');

const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);
These lines load the firebase-functions and firebase-admin modules, and initialize an admin app instance from which Realtime Database changes can be made.

然后你可以这样使用它：

return admin.database().ref().update(updates);

另请参阅此 complete example in the functions-samples repo。

如何在嵌套的 promise Cloud Functions 中限定 Firebase 的范围

How to scope Firebase in nested promise Cloud Functions

javascript

node.js

firebase

google-cloud-functions

Import the required modules and initialize