语法错误：意外的保留字，用于等待循环

Question

我有一个这样的功能：

exports.deleteUser = functions.https.onCall(async(data, context) => {
    let id = context.auth.uid;
    console.log('Delete user: ' + id);

    //delete from algolia
    usersIndex.deleteObject(id);
    console.log(id + 'Deleted from algolia');

    //delete user following
    await admin.firestore().collection('users').doc(id).collection('Following').get()
      .then(async(snapshot) => {
        for await (const document of snapshot.docs) {
          await admin.firestore().collection('users').doc(document.documentId)
            .update({
              'NumberOfFollowers': FieldValue.increment(-1)
            });
          await admin.firestore().collection('users').doc(document.documentId).collection('Followers')
            .doc(id).delete();
        }
        return console.log('Following of ' + id + ' deleted');
      });
...

但是当我尝试将它部署到 firebase 函数时，我收到以下错误：

!  functions[deleteUser(us-central1)]: Deployment error.
Function failed on loading user code. Error message: Code in file index.js can't be loaded.
Is there a syntax error in your code?
Detailed stack trace: /srv/index.js:47
            for await (const document of snapshot.docs) {
                ^^^^^

SyntaxError: Unexpected reserved word
    at createScript (vm.js:80:10)
    at Object.runInThisContext (vm.js:139:10)
    at Module._compile (module.js:617:28)
    at Object.Module._extensions..js (module.js:664:10)
    at Module.load (module.js:566:32)
    at tryModuleLoad (module.js:506:12)
    at Function.Module._load (module.js:498:3)
    at Module.require (module.js:597:17)
    at require (internal/module.js:11:18)
    at getUserFunction (/worker/worker.js:439:24)

发现这个：https : //github.com/nodejs/node/issues/21617但我确实在异步函数中设置了我的 ForLoop ......

Answer 1

for-await 循环首先在 node 版本 10 中可用。您可能在本地或在 package.json 中使用较早的节点版本。

您需要确保在用于部署的本地节点中至少使用节点 10：

$ node --version
...should print 10.x.x or later

并在 package.json 中定位节点 10，以便可以告诉 Cloud Functions 使用哪个版本进行部署：

  "engines": {
    "node": "10"
  }