Class: Hootenanny::Subscription

Inherits:
ActiveRecord::Base
  • Object
show all
Extended by:
Chronological
Defined in:
app/models/hootenanny/subscription.rb

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.subscribe(options = {}) ⇒ Object

Private: Subscribes a given subscriber to a given topic URL by creating a Subscription.

This operation is idempotent. It will not modify a subscription if one already exists for the subscriber/topic passed in.

options - A Hash of options

:subscriber     - A String representing the URI which should be
                  notified when changes occur on the topic
:to             - A String representing the topic URI which is
                  publishing the items that the subscriber is
                  interested in.
:digest_secret  - A String token of no more than 200 bytes which
                  will be used during content distribution so that
                  the subscriber can verify that the request is
                  from the hub and not a undesired 3rd party
                  (optional).
:lease_duration - A Number representing the length of time (in
                  seconds) after the subscription is created until
                  it should be considered invalid

Example:

# If a subscription does not yet exist for the subscriber/topic, it
# creates # a new Subscription

Subscription.subscribe(subscriber: 'http://example.com/my_callback',
                       to:         'http://example.org/my_topic')

# => <Subscription subscriber:  'http://example.com/my_callback',
                   topic:       'http://example.org/my_topic'>

# If a subscription already exists for the subscriber/topic, it retrieves
# and returns the current Subscription with all other attributes updated
# as if the subscription were new.

Subscription.subscribe(subscriber:    'http://example.com/my_callback',
                       to:            'http://example.org/my_topic',
                       digest_secret: 'new_secret')

# => <Subscription subscriber:    'http://example.com/my_callback',
                   topic:         'http://example.org/my_topic',
                   digest_secret: 'new_secret'>

Returns a Subscription Raises a Hootenanny::URI::InvalidSchemeError if the URIs are using something

other than HTTP or HTTPS

Raises a Hootenanny::URI::InvalidError if the URI can’t be parsed properly



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# File 'app/models/hootenanny/subscription.rb', line 91

def self.subscribe(options = {})
  subscriber             = Hootenanny::URI.parse(options.fetch(:subscriber)).to_s
  topic                  = Hootenanny::URI.parse(options.fetch(:to)).to_s

  attrs                  = {}
  attrs[:started_at]     = Time.now.utc
  attrs[:digest_secret]  = options.fetch(:digest_secret, nil)
  attrs[:lease_duration] = options.fetch(:lease_duration)

  subscription = find_or_initialize(subscriber, topic)

  subscription.update_attributes(attrs)

  subscription
end

.to(topic) ⇒ Object

Private: Finds all subscriptions which are subscribed to a given topic

It takes into account only active subscriptions. If the subscription has expired, it will not be returned.

topic - A String represeenting a topic which has been subscribed to

Example:

Subscription.to('http://example.com/foo')
# => <ActiveRelation>

Returns an ActiveRelation which (if it has not been chained) represents the

subscriptions which are subscribed to the topic.



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# File 'app/models/hootenanny/subscription.rb', line 34

def self.to(topic)
  active.where(:topic => topic.to_s)
end

Instance Method Details

#subscriber ⇒ Object 



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# File 'app/models/hootenanny/subscription.rb', line 107

def subscriber
  Hootenanny::URI.parse(read_attribute(:subscriber))
end