ruby-firebase更新和删除？

Question

我正在尝试在我的rails应用中使用Firebase。我希望我的应用中的所有CRUD操作都映射到Firebase中的关联记录。也就是说，如果我添加，编辑或删除“共享”，我希望它在Firebase和通过javascript呈现的HTML中进行更新。我在方法update_firebase和after_destroy中添加了什么？如何告诉firebase从数据库中选择哪条记录？

我正在使用firebase-ruby gem。

以下是我的文件：

#config/initializers/firebase.rb
require 'firebase'
require 'rubygems'
require "firebase_token_generator"

base_uri = 'https://innohack-7bb17.firebaseio.com'

FIREBASE = Firebase::Client.new(base_uri)

payload = {:uid => "1", :auth_data => "foo", :other_auth_data => "bar"}
options = {:admin => true}

generator = Firebase::FirebaseTokenGenerator.new("YOUR_FIREBASE_SECRET")
token = generator.create_token(payload, options)

#app/models/share.rb
class Share < ActiveRecord::Base
  after_create :push_to_firebase
  after_save :update_firebase
  after_destroy :destroy_from_firebase


  include SimpleHashtag::Hashtaggable

  validates :body, presence: true
  belongs_to :user, foreign_key: 'user_id', class_name: "User"

  scope :newest, -> {order("updated_at DESC")}

  has_many :votes, dependent: :destroy
  has_many :comments, dependent: :destroy

  private

  def push_to_firebase
    response = FIREBASE.push("shares", {
      :title => self.title,
      :body => self.body,
      :lat => self.lat,
      :lon => self.lon 
    })
  end

  def update_firebase
  end

  def after_destroy
  end
end

#app/views/shares/index.html.erb
<script src="https://cdn.firebase.com/js/client/1.0.18/firebase.js"></script>

<script src="http://www.webglearth.com/v2/api.js"></script>

<script>
$(function() {
  if (gon.shares.length != 0) {
    var shares = gon.shares;
    var options = {
        center: [shares[shares.length-1].lat, shares[shares.length-1].lon],
        sky: false,
        atmosphere: false,
        zoom: 3,
        tilting: true,
        dragging: true,
    };
  } else {
      var options = {
        sky: false,
        atmosphere: false,
        zoom: 3,
        tilting: true,
        dragging: true,
    };
  };

  earth = new WE.map('earth_div', options);

  WE.tileLayer('http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png').addTo(earth);

  var myFirebaseRef = new Firebase("https://innohack-7bb17.firebaseio.com");
  myFirebaseRef.child("shares").on("child_added", function(snapshot) {
    var lat = snapshot.val().lat;
    var lon = snapshot.val().lon;
    var latLon = [lat, lon];
    var title = snapshot.val().title;
    var body = snapshot.val().body;
    var trimmedBody = body.substring(0, 25);
    var trimmedBody2 = body.substring(25, 100);
    var marker = WE.marker(latLon).addTo(earth);
    marker.bindPopup("<b>" + title + "</b><br>" + trimmedBody + "<br /><span style='font-size:10px;color:#999'>" + trimmedBody2 + "...</span>");
  });
});

</script>

<div class="row">
  <div class="col-xs-12">
    <h1>Shares</h1>
    <br />
  </div>
</div>

<div class="row">
  <div id="earth_div"></div> 
</div>



<div class="row">
  <div class="col-xs-10 col-xs-offset-1 col-sm-8 col-sm-offset-2 col-md-6 col-md-offset-3">
    <% @shares.each do |share| %>
      <div class="booyah-box post">
        <div class="handle">
          <h4><%= link_to share.title, share_path(share) %></h4>
          <p>
          <%= linkify_hashtags(truncate_html(markdown(share.body), length: 100)) %>
          </p>
          <small><%= share.user.name  %></small>
          <p><%= pluralize(share.votes.count, "votes") %></p>
        </div>

        <br />
        <br />

        <% share.comments.first(3).each do |comment| %>
          <blockquote>
            <%= comment.body %><br />
            <small><%= comment.user.email %></small>
          </blockquote>
        <% end %>

        <br />

        <% if share_owner?(share) %>
        <div>
          <div class="btn btn-danger">
            <%= link_to 'Delete', share_path(share), method: :delete, data: {confirm: 'Are you sure?'} %>
          </div>
          <div class="btn btn-warning">
            <%= link_to 'Edit', edit_share_path(share) %>
          </div>
        </div>
      <% end %>
    </div>
  <% end %>
</div>