Module: Mongoid::Tracking::Aggregates::ClassMethods

Defined in:
lib/mongoid/tracking/aggregates.rb

Instance Method Summary collapse

Instance Method Details

#aggregate(name, &block) ⇒ Object

Defines an aggregate token to an already tracked model. It defines a new mongoid model named after the original model.

Example:

class Page include Mongoid::Document include Mongoid::Tracking track :visits aggregate :browsers do |b| b.split(" ").first end end

A new model is defined as class PageAggregates

This model has the following structure:

belongs_to :page field :ns, :type => String field :key, :type => String index [:page_id, :ns, :key], :unique => true track :[original_parent_tracking_data] track :...

:ns is the “namespace”. It’s the name you put along the “aggregate :browsers” in the original model definition.

:key is your aggregation key. This is the value you are required to return in the “aggregate” block.

With the above structure, you can always query aggregates directly  using Mongoid this way:

TestModelAggregates.where(:ns => "browsers", :key => "explorer").first

But you are encouraged to use Trackoid methods whenever possible.

Raises:



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# File 'lib/mongoid/tracking/aggregates.rb', line 60

def aggregate(name, &block)
  raise Errors::AggregationAlreadyDefined.new(self.name, name) if aggregate_fields.has_key? name
  raise Errors::AggregationNameDeprecated.new(name) if DEPRECATED_TOKENS.include? name.to_s

  define_aggregate_model if aggregate_klass.nil?
  has_many internal_accessor_name(name), class_name: aggregate_klass.to_s
  add_aggregate_field(name, block)
  create_aggregation_accessors(name)
end

#aggregated? ⇒ Boolean

Return true if this model has aggregated data.

Returns:

  • (Boolean) 


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# File 'lib/mongoid/tracking/aggregates.rb', line 71

def aggregated?
  !aggregate_klass.nil?
end