同时写入两个数据库引用

我有一个Firebase web应用程序作为注册系统。当用户注册课程时,课程数据作为回调函数的一部分添加到其所有注册的列表中。当用户注册时,最新的类在列表中被复制。在页面加载时,每个课程只列出一次。

实时数据库结构

{
  courses: {
    courseIdA: {
      // course data
    },
    couseIdB ... {}
  },
  users: {
    uid: {
      regs: {
        courseIdA: true
      }
    }
  }
}

member object 以及他们的 users uid courses 和 用户 有没有办法同时给两者写信?或者我需要为数据库设计一个更好的结构吗?

上课,倾听变化

PDReg.prototype.getAllClasses = function() {
  this.database = firebase.database()
  var uid = firebase.auth().currentUser.uid;
  var courses = [];
  var today = new Date().toISOString();

  this.classesRef = this.database.ref('courses');
  this.userRef = this.database.ref('users/' + uid + "/regs");

    var setClass = function(snapshot) {
      var course = snapshot.val();
      course.key = snapshot.key;

      // check for the current user in a course
      if(course.members) {

        if(course.members.hasOwnProperty(uid)) {

          // This callback fires twice when someone registers
          this.buildUserClasses(course);
        } else {
          this.buildAllClasses(course)
        }
      } else {
        this.buildAllClasses(course)
      }
    }.bind(this);

    // listen for changes to the classes database, rebuild the UI
    this.classesRef.orderByChild('start').startAt(today).on('child_added', setClass);
    this.classesRef.on('child_changed', setClass);
};

登记

PDReg.prototype.register = function(e) {
  // It's a form submit, don't reload the page
  e.preventDefault();
  var form = this.courseForm;
  var classes = [];
  var uid = firebase.auth().currentUser.uid;

  for (var i=0; i<form.elements.length; i++) {
    // build the object to submit and add to an array
  }

  for (var i=0; i<classes.length; i++) {
    this.coursesRef = this.database.ref('courses/' + classes[i].id + '/members/' + uid);

    // Write the member object to `courses` under the correct key
    this.coursesRef.set({'code': classes[i]['code']}).then(function(classes) {
    // write to the user ref
    firebase.database().ref('users/' + uid + '/regs/' + id).set(true);
    onSuccess(title);
document.getElementById('allCourses').removeChild(document.getElementById(id))
    }, function(e) {
      onFailure(e, title);
    });
  }
};