Class: Conductor::Weights

Inherits:
Object
  • Object
show all
Defined in:
lib/conductor/weights.rb

Class Method Summary collapse

Class Method Details

.compute(group_name, alternatives) ⇒ Object 



27
28
29
30
31
32
33
34
35
36
37
38
39
40
 
# File 'lib/conductor/weights.rb', line 27

def compute(group_name, alternatives)
  # create the conditions after sanitizing sql.
  alternative_filter = alternatives.inject([]) {|res,x| res << "alternative = '#{Conductor.sanitize(x)}'"}.join(' OR ')

  # pull daily data and recompute if daily data
  group_rows = Conductor::Experiment::Daily.since(14.days.ago).for_group(group_name).find(:all, :conditions => alternative_filter)

  unless group_rows.empty?
    Conductor::Experiment::Weight.delete_all(:group_name => group_name) # => remove all old data for group
    total = group_rows.sum_it(:conversion_value)
    data = total ? compute_weights_for_group(group_name, group_rows, total) : assign_equal_weights(group_rows)
    update_weights_in_db(group_name, data)
  end
end

.find_or_create(group_name, alternatives) ⇒ Object

Returns all the weights for a given group. In the event that the alternatives specified for the group do not match all the alternatives previously computed for the group, new weights are generated. The cache is used to speed up this check



8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
 
# File 'lib/conductor/weights.rb', line 8

def find_or_create(group_name, alternatives)
  weights_for_group = Conductor.cache.read("Conductor::Experiment::#{group_name}::Alternatives")

  alternatives_array = weights_for_group.map(&:alternative).sort if weights_for_group
  if alternatives_array.eql?(alternatives.sort)
    Conductor.log('alternatives equal to cache')
    return weights_for_group
  else
    # Conductor.log('alternatives NOT equal to cache.  Need to recompute')
    compute(group_name, alternatives)

    # get the new weights
    weights_for_group = Conductor::Experiment::Weight.find(:all, :conditions => "group_name = '#{group_name}'")
    Conductor.cache.delete("Conductor::Experiment::#{group_name}::Alternatives")
    Conductor.cache.write("Conductor::Experiment::#{group_name}::Alternatives", weights_for_group)
    return weights_for_group
  end
end