首页 \ 问答 \ 计算Meteor中的帖子数量评论(Count number comments in post in Meteor)

计算Meteor中的帖子数量评论(Count number comments in post in Meteor)

如果我想计算帖子的评论数量,每次创建或删除新评论时,我都必须保存评论数量。

每次创建或删除评论时,确保使用评论数更新帖子的最有效和最安全的方法是什么? 我尝试过Curser.observe()但似乎有时会引起一些问题。 我查看了我的代码,它应该没问题,但有时会发生一些变化,当它们不应该这样时,我担心当多个对象同时创建时,observe()会导致一些问题。

我看过meteor-collection-hooks ,他们不使用observe 。 我认为observe是最好的选择,因为它是原生的。 别人怎么解决这个问题?


If I want to count the number of comments a post has got, I will have to save the number of comments every time a new comment is either created or removed.

What is the most efficient and secure way to ensure the posts are updated with the number of comments every time a comment is either created or removed? I have tried Curser.observe() but it seems it causes some problems sometimes. I have looked through my code and it should be OK but sometimes some changes happend when they shouldn't so I'm afraid that observe() causes some problems when multiple objects are created at the same time.

I have looked at meteor-collection-hooks and they don't use observe. I thought observe was the best choice since it is native. How does others solve this?


原文:https://stackoverflow.com/questions/31190739
更新时间:2020-03-26 14:57

最满意答案

不要使用观察。 它消耗资源并且不会扩展到一个服务器(在N个服务器中观察到更改,您将有N个增量)。 我可以推荐两种可能的选择:

挂钩

如您所建议,您可以使用collection-hooks来修改计数。 具体来说,您可能希望在Comments集合中使用after.insertafter.remove 。 钩子不需要额外的资源 - 它们只是修补底层的集​​合代码来运行你的回调。

推荐阅读: 看看Meteor Collection Hooks

方法

如果您使用方法插入和删除评论,您还可以同时修改评论计数。 这样做的好处是不需要外部包装,但是在您的方法中也需要考虑一些问题。


Don't use observe. It consumes resources and doesn't scale past one server (in N servers are observing the change, you will have N increments). I can recommend two possible options:

hooks

As you suggested, you can use collection-hooks to modify the count. Specifically you'd probably want to use after.insert and after.remove on your Comments collection. Hooks don't require extra resources - they just patch the underlying collection code to run your callback.

Recommended reading: A Look At Meteor Collection Hooks

methods

If you use methods to insert and remove your comments, you can also modify your comment counts at the same time. This has the advantage of not requiring an external package, however it also requires some mixing of concerns in your methods.

2015-07-02

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