Question

我指的是这里给出的例子： docs.meteor.com/#publish_added 我已经阅读了答案： How does the messages-count example in Meteor docs work?

我想跟踪3个独立集合中的条目数。将值存储在名为counts的集合中。与示例不同，我不需要过滤表格（通过roomId）。

我在服务器上的

：

Meteor.publish("counts-all", function () {
var self = this;

var pcount = 0;
var fcount = 0;
var scount = 0;
var initializing = true;

// observeChanges only returns after the initial `added` callbacks
// have run. Until then, we don't want to send a lot of
// `self.changed()` messages - hence tracking the
// `initializing` state.
var phandle = Persons.find({}).observeChanges({
  added: function (id) {
    pcount++;
    if (!initializing)
      self.changed('counts', 'persons', {count: pcount});
      // self.changed('counts', 0, {count: pcount});
  },
  removed: function (id) {
    pcount--;
    self.changed('counts', 'persons', {count: pcount});
    // self.changed('counts', 0, {count: pcount});
  }
  // don't care about changed
});

var fhandle = Families.find({}).observeChanges({
  added: function (id) {
    fcount++;
    if (!initializing)
      self.changed('counts', 'families', {count: fcount});
      // self.changed('counts', 1, {count: fcount});
  },
  removed: function (id) {
    fcount--;
    self.changed('counts', 'families', {count: fcount});
    // self.changed('counts', 1, {count: fcount});
  }
  // don't care about changed
});

var shandle = Sources.find({}).observeChanges({
  added: function (id) {
    scount++;
    if (!initializing)
      self.changed('counts', 'sources', {count: scount});
      // self.changed('counts', 2, {count: scount});
  },
  removed: function (id) {
    scount--;
    self.changed('counts', 'sources', {count: scount});
    // self.changed('counts', 2, {count: scount});
  }
  // don't care about changed
});

// Instead, we'll send one `self.added()` message right after
// observeChanges has returned, and mark the subscription as
// ready.
console.log('publish counts: '+pcount+' '+fcount+' '+scount);
initializing = false;

self.added('counts', 'persons', {count: pcount});
self.added('counts', 'families', {count: fcount});
self.added('counts', 'sources', {count: scount});


self.ready();

// Stop observing the cursor when client unsubs.
// Stopping a subscription automatically takes
// care of sending the client any removed messages.
self.onStop(function () {
  phandle.stop();
  fhandle.stop();
  shandle.stop();
});
});

我可以从我的日志记录中看到它确实计算出每个集合的记录总数：发表人数：168 150 36

在客户端，我有：

Counts = new Meteor.Collection("counts");

Deps.autorun(function () {
console.log('inside autorun');
Meteor.subscribe("counts-all");
console.log(Counts.find({}));
});

日志记录不会显示集合中的条目。我如何在客户端上引用这些项目？ Counts.findOne（{_ id：'persons'}）。count

此外，在我提到的问题中，网站示例和响应之间存在差异：

使用Dep vs Tracker
添加和删除哈希函数的不同参数
使用Mongo.collection与Meteor.collection。

指导将不胜感激

Answer 1

您可以通过以下方式访问客户端counts：

    Deps.autorun(function () {
        console.log('inside autorun');
        Meteor.subscribe("counts-all");
        console.log(Counts.find({_id:"persons"}).fetch());
        var persons     = Counts.findOne({_id:"persons"}) || {};
        var sources     = Counts.findOne({_id:"sources"}) || {} ;
        var families    = Counts.findOne({_id:"families"}) || {};
        console.log(persons.count, sources.count, families.count);
    });

在v0.9.1中引入了{p> Mongo.collection vs Meteor.collection和Deps -> Tracker更改。

如何调整Meteor消息计数示例以跟踪多个集合？

1 个答案: