Class: Verdict::Segmenters::BaseSegmenter

Inherits:
Object
  • Object
show all
Defined in:
lib/verdict/segmenters/base_segmenter.rb

Overview

Base class of all segmenters.

The segmenter is responsible for assigning subjects to groups. You can implement any assignment strategy you like by subclassing this class and using it in your experiment.

  • You should implement the register_group method for the experiment definition DSL to make the system aware of the groups that the segmenter could return.

  • The verify! method is called after all the groups have been defined, so it can detect internal inconsistencies in the group definitions.

  • The assign method is where your assignment magic lives.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(experiment) ⇒ BaseSegmenter

Returns a new instance of BaseSegmenter.



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# File 'lib/verdict/segmenters/base_segmenter.rb', line 22

def initialize(experiment)
  @experiment = experiment
  @groups = {}
end

Instance Attribute Details

#experiment ⇒ Object (readonly)

The experiment to which this segmenter is associated



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# File 'lib/verdict/segmenters/base_segmenter.rb', line 16

def experiment
  @experiment
end

#groups ⇒ Object (readonly)

A hash of the groups that are defined in this experiment, indexed by their handle. The assign method should return one of the groups in this hash



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# File 'lib/verdict/segmenters/base_segmenter.rb', line 20

def groups
  @groups
end

Instance Method Details

#assign(identifier, subject, context) ⇒ Object

The assign method is called to assign a subject to one of the groups that have been defined in the segmenter implementation.

  • The identifier parameter is a string that uniquely identifies the subject.

  • The subject paramater is the subject instance that was passed to the framework, when the application code calls Experiment#assign or Experiment#switch.

  • The context parameter is an object that was passed to the framework, you can use this object any way you like in your segmenting logic.

This method should return the Verdict::Group instance to which the subject should be assigned. This instance should be one of the group instance that was registered in the definition DSL.

Raises:

  • (NotImplementedError) 


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# File 'lib/verdict/segmenters/base_segmenter.rb', line 64

def assign(identifier, subject, context)
  raise NotImplementedError
end

#conversion_feedback(identifier, subject, conversion) ⇒ Object

This method is called whenever a subjects converts to a goal, i.e., when Experiment#convert is called. You can use this to implement a feedback loop in your segmenter.

  • The identifier parameter is a string that uniquely identifies the subject.

  • The subject paramater is the subject instance that was passed to the framework, when the application code calls Experiment#assign or Experiment#switch.

  • The conversion parameter is a Verdict::Conversion instance that describes what goal the subject converted to.

The return value of this method is not used.



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# File 'lib/verdict/segmenters/base_segmenter.rb', line 79

def conversion_feedback(identifier, subject, conversion)
  # noop by default
end

#group(handle, *args, &block) ⇒ Object

DSL method to register a group. It calls the register_group method of the segmenter implementation



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# File 'lib/verdict/segmenters/base_segmenter.rb', line 29

def group(handle, *args, &block)
  group = register_group(handle, *args)
  @groups[group.handle] = group
  group.instance_eval(&block) if block_given?
end

#register_group(handle, *args) ⇒ Object

The group method is called from the experiment definition DSL. It should register a new group to the segmenter, with the given handle.

  • The handle parameter is a symbol that uniquely identifies the group within this experiment.

  • The return value of this method should be a Verdict::Group instance.

Raises:

  • (NotImplementedError) 


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# File 'lib/verdict/segmenters/base_segmenter.rb', line 41

def register_group(handle, *args)
  raise NotImplementedError
end

#verify! ⇒ Object

The verify! method is called after all the groups have been defined in the experiment definition DSL. You can run any consistency checks in this method, and if anything is off, you can raise a Verdict::SegmentationError to signify the problem.



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# File 'lib/verdict/segmenters/base_segmenter.rb', line 49

def verify!
  # noop by default
end