如何从Meteor.method与普通代码中调用Meteor数据库更改器? [英] How does a Meteor database mutator know if it's being called from a Meteor.method vs. normal code?

问题描述

如果某人在客户端上做某事

If one does something on the client like

Foo.insert({blah : 1})

其中Foo是Meteor集合，实际上会触发 http://docs.meteor.com/#meteor_methods ，该代码可在客户端和服务器上执行代码.

where Foo is a Meteor collection, this actually triggers a Meteor.method call as documented in the last paragraph of http://docs.meteor.com/#meteor_methods that executes code on both the client and the server.

但是，假设我定义了一个在客户端和服务器上执行相同操作的方法:

However, let's say I define a method (on client and server) that does the same thing:

Meteor.methods({
  bar: function() { 
    Foo.insert({blah : 1}) 
  }
});

现在，我用

Meteor.call("bar");

作为方法的结果，现在将在客户端和服务器上同时调用

Foo.insert.但是，insert的客户端调用如何知道不再调用服务器，因为它本身就是方法?

Foo.insert will now be called both on the client and the server as a result of the method. However, how does the client-side invocation of insert know not to call the server again, since it is itself a method?

此外，有没有办法在客户端无的情况下调用insert，而不会自动触发规范的服务器端延迟补偿调用并产生同步? (有关为何要执行此操作的原因，请参见使用伪造的即弃数据加载Meteor客户端应用)

Moreover, is there a way to call insert on the client side without automatically triggering the canonical server-side latency-compensation call and resulting synchronization? (For why I'd want to do this, see Loading a Meteor client app with fake fire-and-forget data)

推荐答案

客户端一成为存根".它具有此isSimulation属性设置，使其看起来好像为延迟补偿插入了数据.

The client side one becomes a 'stub'. It has this isSimulation property set that makes it appear as if the data is inserted for latency compensation.

我认为，如果在客户端上运行.method，则始终启用延迟补偿，并且不应将其输入数据库.因此，在客户端方法上运行的任何东西都将是伪"类型的模拟

I think if a .method is run on the client the latency compensation is always enabled and it shouldn't enter in the database. So anything running on a client side method would be a 'fake' type simulation

如果您尝试将this.isSimulation设置为false，则会收到一些奇怪的错误，表明您的客户端插入内容开始对插入内容引发错误.

If you try setting this.isSimulation to false you'll get some weird error that shows you that the client side insert starts to throw errors with the insert.

我不太确定如何在错误的模拟中运行它.我认为您必须使用其他方法var dothis = function() {...}类型的方法来运行它.

I'm not too sure how to run it in a false simulation. I think you'd have to run it off in some other method var dothis = function() {...} type method.

要进行这种假冒"行为，忘记并且只有客户端数据，这就是我所假定的(如果我错了，请更正，以便更改答案)，然后在您的客户端方法中修改_collection属性.

To do this 'fake fire' & forget and have client side only data, which is what I presume (please correct if I'm wrong so I change the answer) modify the _collection property in your client side method.

例如，如果有

mydata = new Meteor.Collection("something");

function something() {
    mydata.insert({..});
}

修改方法来代替

mydata._collection.insert({..});

这将确保数据未同步到服务器，但将使本地集合具有此伪数据".

This will make sure that the data isn't synchronized to the server, yet will have the local collection have this 'fake data'.

希望这会有所帮助！

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