Module: Mongoid::CollectionSnapshot

Extended by:
ActiveSupport::Concern
Defined in:
lib/mongoid_collection_snapshot/version.rb,
lib/mongoid_collection_snapshot.rb

Defined Under Namespace

Modules: ClassMethods

Constant Summary collapse

VERSION = 
'1.0.1'

Instance Method Summary collapse

Instance Method Details

#collection_snapshot(name = nil) ⇒ Object 



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# File 'lib/mongoid_collection_snapshot.rb', line 29

def collection_snapshot(name=nil)
  if name
    snapshot_session["#{self.collection.name}.#{name}.#{slug}"]
  else
    snapshot_session["#{self.collection.name}.#{slug}"]
  end
end

#drop_snapshot_collections ⇒ Object 



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# File 'lib/mongoid_collection_snapshot.rb', line 37

def drop_snapshot_collections
  snapshot_session.collections.each do |collection|
    collection.drop if collection.name =~ /^#{self.collection.name}\.([^\.]+\.)?#{slug}$/
  end
end

#ensure_at_most_two_instances_exist ⇒ Object

Since we should always be using the latest instance of this class, this method is called after each save - making sure only at most two instances exists should be sufficient to ensure that this data can be rebuilt live without corrupting any existing computations that might have a handle to the previous “latest” instance.



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# File 'lib/mongoid_collection_snapshot.rb', line 47

def ensure_at_most_two_instances_exist
  all_instances = self.class.order_by([[:created_at, :desc]]).to_a
  if all_instances.length > self.max_collection_snapshot_instances
    all_instances[self.max_collection_snapshot_instances..-1].each { |instance| instance.destroy }
  end
end

#snapshot_session ⇒ Object

Override to supply custom database connection for snapshots



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# File 'lib/mongoid_collection_snapshot.rb', line 55

def snapshot_session
  Mongoid.default_session
end