04s-publications-and-subscriptions.md.erb

---
title: Publications and Subscriptions
slug: publications-and-subscriptions
date: 0004/01/02
number: 4.5
sidebar: true
contents: Understand how publications and subscriptions work.|Learn what the default Autopublish package does.|See a few more examples of publication patterns.
paragraphs: 52
---

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### The Olden Days

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### The Meteor Way

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<%= diagram "client-server", "Pushing a subset of the database to the client.", "pull-right" %>

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### Publishing

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<%= diagram "collections-1", "All the posts contained in our database.", "pull-center" %>

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<%= diagram "collections-2", "Excluding flagged posts.", "pull-center" %>

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~~~js
// on the server
Meteor.publish('posts', function() {
  return Posts.find({flagged: false}); 
});
~~~

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<% note do %>

### DDP

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<% end %>

### Subscribing

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<%= diagram "collections-3", "Subscribing to Bob's posts will mirror them on the client.", "pull-center" %>

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~~~js
// on the server
Meteor.publish('posts', function(author) {
  return Posts.find({flagged: false, author: author});
});
~~~

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~~~js
// on the client
Meteor.subscribe('posts', 'bob-smith');
~~~

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### Finding

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<%= diagram "collections-4", "Selecting a subset of documents on the client.", "pull-center" %>

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~~~js
// on the client
Template.posts.helpers({
  posts: function(){
    return Posts.find(author: 'bob-smith', category: 'JavaScript');
  }
});
~~~

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### Autopublish

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<%= diagram "autopublish", "Autopublish", "pull-center"%>

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### Publishing Full Collections

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~~~js 
Meteor.publish('allPosts', function(){
  return Posts.find();
});
~~~

<%= diagram "fullcollection", "Publishing a full collection", "pull-center" %>

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### Publishing Partial Collections

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~~~js 
Meteor.publish('somePosts', function(){
  return Posts.find({'author':'Tom'});
});
~~~

<%= diagram "partialcollection", "Publishing a partial collection", "pull-center" %>

<% note do %>

### Behind The Scenes

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- ////
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- ////

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<% end %>

### Publishing Partial Properties

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~~~js
Meteor.publish('allPosts', function(){
  return Posts.find({}, {fields: {
    date: false
  }});
});
~~~

<%= diagram "partialproperties", "Publishing partial properties", "pull-center" %>

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~~~js
Meteor.publish('allPosts', function(){
  return Posts.find({'author':'Tom'}, {fields: {
    date: false
  }});
});
~~~

### Summing Up

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