即时创建新的 Meteor 集合 [英] Creating new Meteor collections on the fly

问题描述

是否可以即时创建新的 Meteor 收藏?我想根据某个路径名创建 foo_bar 或 bar_bar，我想这应该是一个全局变量(这样我就可以在整个应用程序中访问它).
类似的东西:

Is it possible to create new Meteor collections on-the-fly? I'd like to create foo_bar or bar_bar depending on some pathname which should be a global variable I suppose (so I can access it throughout my whole application).
Something like:

var prefix = window.location.pathname.replace(/^/([^/]*).*$/, '$1');
var Bar = new Meteor.Collection(prefix+'_bar');

这里的问题是我应该从 URL 获取我的 prefix 变量，所以如果我在 if (Meteor.isClient) 之外声明它，我会收到一个错误:<代码>参考错误:窗口未定义.有可能做这样的事情吗?

The thing here is that I should get my prefix variable from URL, so if i declare it outside of if (Meteor.isClient) I get an error: ReferenceError: window is not defined. Is it possible to do something like that at all?

编辑:使用 Akshats 的第一次迭代回答我的项目 js:http://pastie.org/6411287

Edit : Using the first iteration of Akshats answer my project js : http://pastie.org/6411287

推荐答案

我不完全确定这会奏效:

I'm not entirely certain this will work:

你需要把它分成两部分，第一部分加载你之前设置的集合(在客户端和服务器上)

You need it in two pieces, the first to load collections you've set up before (on both the client and server)

var collections = {};
var mysettings = new Meteor.Collection('settings') //use your settings

//Startup
Collectionlist = mysettings.find({type:'collection'});

Collectionlist.forEach(function(doc) {
    collections[doc.name] = new Meteor.Collection(doc.name);
})'

并且您需要在服务器上添加集合:

And you need a bit to add the collections on the server:

Meteor.methods({
    'create_server_col' : function(collectionname) {
       mysettings.insert({type:'collection', name: collectionname});
       newcollections[collectionname] = new Collection(collectionname);
       return true;
    }
});

并且您需要在客户端上创建它们:

And you need to create them on the client:

//Create the collection:

Meteor.call('create_server_col', 'My New Collection Name', function(err,result) {
    if(result) {
        alert("Collection made");
    }
    else
    {
        console.log(err);
    }
}

同样，这一切都未经测试，所以我只是试一试，希望它能奏效.

Again, this is all untested so I'm just giving it a shot hopefully it works.

编辑

也许下面应该可以工作，我已经添加了一些检查以查看集合是否首先存在.请您先运行meteor reset，然后再使用它从上面的代码中对错误进行排序:

Perhaps the below should work, I've added a couple of checks to see if the collection exists first. Please could you run meteor reset before you use it to sort bugs from the code above:

var collections = {};
var mysettings = new Meteor.Collection('settings')

if (Meteor.isClient) {
  Meteor.startup(function() {
    Collectionlist = mysettings.find({type:'collection'});

    Collectionlist.forEach(function(doc) {
        eval("var "+doc.name+" = new Meteor.Collection("+doc.name+"));
    });
  });
  Template.hello.greeting = function () {
    return "Welcome to testColl.";
  };

  var collectionname=prompt("Enter a collection name to create:","collection name")

  create_collection(collectionname);

  function create_collection(name) {
    Meteor.call('create_server_col', 'tempcoll', function(err,result) {
        if(!err) {
            if(result) {
                //make sure name is safe
                eval("var "+name+" = new Meteor.Collection('"+name+"'));
                alert("Collection made");
                console.log(result);
                console.log(collections);
            } else {
                alert("This collection already exists");
            }
        }
        else
        {
            alert("Error see console");
            console.log(err);
        }
    });
  }
}

if (Meteor.isServer) {
  Meteor.startup(function () {
    // code to run on server at startup
    Collectionlist = mysettings.find({type:'collection'});

    Collectionlist.forEach(function(doc) {
        collections[doc.name] = new Meteor.Collection(doc.name);
    });
  });

  Meteor.methods({
    'create_server_col' : function(collectionname) {
       if(!mysettings.findOne({type:'collection', name: collectionname})) {
        mysettings.insert({type:'collection', name: collectionname});

        collections[collectionname] = new Meteor.Collection(collectionname);

        return true;
       }
       else
       {
        return false; //Collection already exists
       }
    }
  });
}

还要确保你的名字是 javascript 转义的.

Also make sure your names are javascript escaped.

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