Question

我正在尝试为特定用户的关注者设置通知，以便每当他们关注的用户发布一章时，所有用户的关注者都会收到通知。我正在使用https://github.com/rails-engine/notifications。

根据本教程https://www.devwalks.com/lets-build-instagram-with-ruby-on-rails-part-6-follow-all-the-people/

，我实现了以下关系，这些关系在我的应用程序上运行良好

这是我到目前为止对代码所做的

user.rb

  has_many :books, dependent: :destroy
  has_many :chapters, dependent: :destroy
  has_many :reviews, dependent: :destroy
  has_many :genres
  has_many :ratings

chapter.rb

belongs_to :book
belongs_to :user

after_commit :create_notifications, on: :create

private

def create_notifications
   Notification.create do |notification|
      notification.notify_type = 'chapter'
      notification.actor = self.book.user
      notification.user = self.user.followers
      notification.target = self
      notification.second_target = self.book
    end
end

views / notifications / _chapter.html.erb

<div class=''>
  <%= link_to notification.actor.username, main_app.profile_path(notification.actor.username) %> published a new chapter to 
  <%= link_to notification.second_target.title, main_app.book_path(notification.second_target) %>
</div>

<div class=''>
  <% unless notification.target.blank? %>
    <%= link_to notification.target.title, main_app.book_chapter_path(notification.second_target, notification.target.id) %>
  <% end %>
</div>

book.rb

belongs_to :user
has_many :chapters, dependent: :destroy

当我将通知定向给自己时，我得到了正确的通知，但是当我执行上述通知时，我得到了错误：

User(#58266780) expected, got #<ActiveRecord::Associations::CollectionProxy [#<User id: 3, name: "Otunba Olusaga of Saganation", username: "saga", email: "officialklashe@gmail.com", created_at: "2019-03-26 11:59:16", updated_at: "2019-03-27 09:13:58", admin: false, bio: "">]> which is an instance of User::ActiveRecord_Associations_CollectionProxy(#58325780)

更多研究表明，我必须“映射关注者（或使用批处理插入工具）以插入多个通知”，而我不知道该怎么做。

对此示例代码进行说明将非常有帮助，谢谢！

Answer 1

我不确定您是否可以在这种情况下进行批量插入，因为我了解到，Notification gem需要每个通知都针对单个用户吗？也许这样做...

def create_notifications
   self.user.followers.each do |follower|
     Notification.create(notify_type: 'chapter', actor: self.book.user,
                         user: follower, target: self, second_target: self.book)

   end
end

如何使用“ Notifications gem”为关注者创建通知

1 个答案: