我试图使一个谷歌云功能删除链接到Firebase实时数据库中的人对象的图像。但是每次我得到“请求期间出错”错误（没有任何具体的错误代码，它只是未定义）。下面是一个函数代码：

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

// The Firebase Admin SDK to access the Firebase Realtime Database.
const admin = require('firebase-admin');
const gcs = require('@google-cloud/storage')({ 
  projectId: "PROJ_ID",
  keyFilename: "SERV_ACC.json LOCATED IN FUNCTIONS FOLDER"});

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

exports.removePersonImage = 
functions.database.ref("users/{userId}/persons/{personId}")
 .onDelete((snapshot, context) => {
   const person = snapshot.val();    

   if (!person.photo || !person.photo.key) {
    console.log("Person doesn't have photo");
    return true;
   }

   var path = "user/" + context.params.userId + "/" + person.photo.key + ".jpg";

   console.log("Bucket path: " + path);

   return gcs.bucket(path)
    .delete()
    .then(() => {
      console.log("Image " + person.photo.key + " successfully deleted");
      return true;
    })
    .catch(err => {
      console.error("Failed to remove image " + person.photo.key);
      console.error("Error: " + err.message);
      return false;
    });
});

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