Class: Vanity::Experiment::Base

Inherits:
Object
  • Object
show all
Defined in:
lib/vanity/experiment/base.rb

Overview

Base class that all experiment types are derived from.

Direct Known Subclasses

AbTest

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(playground, id, name, options = nil) ⇒ Base

Returns a new instance of Base.



67
68
69
70
71
72
 
# File 'lib/vanity/experiment/base.rb', line 67

def initialize(playground, id, name, options = nil)
  @playground = playground
  @id, @name = id.to_sym, name
  @options = options || {}
  @identify_block = method(:default_identify)
end

Instance Attribute Details

#completed_at ⇒ Object (readonly)

Time stamp when experiment was completed.



89
90
91
 
# File 'lib/vanity/experiment/base.rb', line 89

def completed_at
  @completed_at
end

#id ⇒ Object (readonly)

Unique identifier, derived from name experiment name, e.g. “Green Button” becomes :green_button.



81
82
83
 
# File 'lib/vanity/experiment/base.rb', line 81

def id
  @id
end

#name ⇒ Object (readonly) Also known as: to_s

Human readable experiment name (first argument you pass when creating a new experiment).



76
77
78
 
# File 'lib/vanity/experiment/base.rb', line 76

def name
  @name
end

Class Method Details

.load(playground, stack, file) ⇒ Object

Playground uses this to load experiment definitions.



45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
 
# File 'lib/vanity/experiment/base.rb', line 45

def load(playground, stack, file)
  fail "Circular dependency detected: #{stack.join('=>')}=>#{file}" if stack.include?(file)
  source = File.read(file)
  stack.push file
  id = File.basename(file, ".rb").downcase.gsub(/\W/, "_").to_sym
  context = Object.new
  context.instance_eval do
    extend Definition
    experiment = eval(source, context.new_binding(playground, id), file)
    fail NameError.new("Expected #{file} to define experiment #{id}", id) unless playground.experiments[id]
    experiment
  end
rescue
  error = NameError.exception($!.message, id)
  error.set_backtrace $!.backtrace
  raise error
ensure
  stack.pop
end

.type ⇒ Object

Returns the type of this class as a symbol (e.g. AbTest becomes ab_test).



40
41
42
 
# File 'lib/vanity/experiment/base.rb', line 40

def type
  name.split("::").last.gsub(/([a-z])([A-Z])/) { "#{$1}_#{$2}" }.gsub(/([A-Z])([A-Z][a-z])/) { "#{$1}_#{$2}" }.downcase
end

Instance Method Details

#active? ⇒ Boolean

Returns true if experiment active, false if completed.

Returns:

  • (Boolean) 


155
156
157
 
# File 'lib/vanity/experiment/base.rb', line 155

def active?
  !@playground.collecting? || !connection.is_experiment_completed?(@id)
end

#complete! ⇒ Object

Force experiment to complete.



142
143
144
145
146
147
 
# File 'lib/vanity/experiment/base.rb', line 142

def complete!
  @playground.logger.info "vanity: completed experiment #{id}"
  return unless @playground.collecting?
  connection.set_experiment_completed_at @id, Time.now
  @completed_at = connection.get_experiment_completed_at(@id)
end

#complete_if(&block) ⇒ Object

Define experiment completion condition. For example:

complete_if do
  !score(95).chosen.nil?
end

Raises:

  • (ArgumentError) 


135
136
137
138
139
 
# File 'lib/vanity/experiment/base.rb', line 135

def complete_if(&block)
  raise ArgumentError, "Missing block" unless block
  raise "complete_if already called on this experiment" if @complete_block
  @complete_block = block
end

#created_at ⇒ Object

Time stamp when experiment was created.



84
85
86
 
# File 'lib/vanity/experiment/base.rb', line 84

def created_at
  @created_at ||= connection.get_experiment_created_at(@id)
end

#description(text = nil) ⇒ Object

Sets or returns description. For example

ab_test "Simple" do
  description "A simple A/B experiment"
end

puts "Just defined: " + experiment(:simple).description



123
124
125
126
 
# File 'lib/vanity/experiment/base.rb', line 123

def description(text = nil)
  @description = text if text
  @description
end

#destroy ⇒ Object

Get rid of all experiment data.



162
163
164
165
 
# File 'lib/vanity/experiment/base.rb', line 162

def destroy
  connection.destroy_experiment @id
  @created_at = @completed_at = nil
end

#identify(&block) ⇒ Object

Defines how we obtain an identity for the current experiment. Usually Vanity gets the identity form a session object (see use_vanity), but there are cases where you want a particular experiment to use a different identity.

For example, if all your experiments use current_user and you need one experiment to use the current project:

ab_test "Project widget" do
  alternatives :small, :medium, :large
  identify do |controller|
    controller.project.id
  end
end



109
110
111
112
 
# File 'lib/vanity/experiment/base.rb', line 109

def identify(&block)
  fail "Missing block" unless block
  @identify_block = block
end

#save ⇒ Object

Called by Playground to save the experiment definition.



168
169
170
171
 
# File 'lib/vanity/experiment/base.rb', line 168

def save
  return unless @playground.collecting?
  connection.set_experiment_created_at @id, Time.now
end

#type ⇒ Object

Returns the type of this experiment as a symbol (e.g. :ab_test).



92
93
94
 
# File 'lib/vanity/experiment/base.rb', line 92

def type
  self.class.type
end