Vulcan/packages/vulcan-subscribe

vulcan:subscribe

This optional package for Vulcan lets your users subscribe to the different domains (collections) of your application.

Dependencies & usage

Explicit dependency on vulcan:users to enable permissions.

If vulcan:posts is enabled, your users will be able to subscribe to:

• new posts from users they follow (subscribed to)
• new comments on a post they are subscribed to

If vulcan:categories is enabled, your users will be able to subscribe to new posts in a category.

Basic usage

This package gives you access to several methods of the type collection.subscribe & collection.unsubscribe. Default group of users can subscribe to any activated domain (see above) with the following methods (action) :

users.subscribe
users.unsubscribe
posts.subscribe
posts.unsubscribe
categories.subscribe
categories.unsubscribe

This package also provides a reusable component called SubscribeTo to subscribe to an document of collection.

This component takes the document as a props. It can trigger any method described below:

// for example, in PostItem.jsx
<Components.SubscribeTo document={post} />

// for example, in UsersProfile.jsx
<Components.SubscribeTo document={user} />

// for example, in Category.jsx
<Components.SubscribeTo document={category} />

Extend to other collections than Users, Posts, Categories

This package exports a function called subscribeMutationsGenerator that takes a collection as an argument and create the associated methods code :

// in my custom package
import subscribeMutationsGenerator from 'meteor/vulcan:subscribe';
import Movies from './collection.js';

// the function creates the code and give it to the graphql server
subscribeMutationsGenerator(Movies);

This will creates for you the mutations moviesSubscribe & moviesUnsubscribe than can be used in the SubscribeTo component:

// in my custom component
<Components.SubscribeTo document={movie} />

You'll also need to write the relevant callbacks, custom fields & permissions to run whenever a user is subscribed to your custom collection's item. See these files for inspiration. Note: it's more or less always the same thing

• Custom fields: https://github.com/TelescopeJS/Telescope/blob/devel/packages/vulcan-subscribe/lib/custom_fields.js#L47-L75
• Callbacks: https://github.com/TelescopeJS/Telescope/blob/devel/packages/vulcan-subscribe/lib/callbacks.js#L13-L36
• Permissions: https://github.com/TelescopeJS/Telescope/blob/devel/packages/vulcan-subscribe/lib/permissions.js

Reusable component to show a list of subscribed items

There was formerly a component that showed a list of subscribed posts. While reducing the depencies to other packages, it broke. It's on the roadmap to re-enable it. Feel free to discuss about it on the Slack channel if you want to build it!

Original PR & discussion can be found here: https://github.com/TelescopeJS/Telescope/pull/1425