Class: Hackle::Client

Inherits:
Object
  • Object
show all
Defined in:
lib/hackle/client.rb

Overview

A client for Hackle API.

Instance Method Summary collapse

Constructor Details

#initialize(config:, workspace_fetcher:, event_processor:, decider:) ⇒ Client

Initializes a Hackle client.

Parameters:



39
40
41
42
43
44
45
46
47
48
49
50
 
# File 'lib/hackle/client.rb', line 39

def initialize(config:, workspace_fetcher:, event_processor:, decider:)
  @logger = config.logger

  # @type [PollingWorkspaceFetcher]
  @workspace_fetcher = workspace_fetcher

  # @type [EventProcessor]
  @event_processor = event_processor

  # @type [Decider]
  @decider = decider
end

Instance Method Details

#close ⇒ Object

Shutdown the background task and release the resources used for the background task.



122
123
124
125
 
# File 'lib/hackle/client.rb', line 122

def close
  @workspace_fetcher.stop!
  @event_processor.stop!
end

#track(event:, user:) ⇒ Object

Records the event that occurred by the user.

Parameters:

  • event (Event) —

    the event that occurred.

  • user (User) —

    the user that occurred the event.



103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
 
# File 'lib/hackle/client.rb', line 103

def track(event:, user:)

  return if event.nil? || !event.is_a?(Event) || !event.valid?
  return if user.nil? || !user.is_a?(User) || !user.valid?

  workspace = @workspace_fetcher.fetch
  return if workspace.nil?

  event_type = workspace.get_event_type(event_type_key: event.key)
  track_event = UserEvent::Track.new(user: user, event_type: event_type, event: event)
  @event_processor.process(event: track_event)

rescue => e
  @logger.error { "Unexpected error while tracking event: #{e.inspect}" }
end

#variation(experiment_key:, user:, default_variation: 'A') ⇒ String

Decide the variation to expose to the user for experiment.

This method return the control variation ‘A’ if:

  • The experiment key is invalid

  • The experiment has not started yet

  • The user is not allocated to the experiment

  • The decided variation has been dropped

Parameters:

  • experiment_key (Integer) —

    The unique key of the experiment. MUST NOT be nil.

  • user (User) —

    the user to participate in the experiment. MUST NOT be nil.

  • default_variation (String) (defaults to: 'A') —

    The default variation of the experiment.

Returns:

  • (String) —

    The decided variation for the user, or default variation



67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
 
# File 'lib/hackle/client.rb', line 67

def variation(experiment_key:, user:, default_variation: 'A')

  return default_variation if experiment_key.nil? || !experiment_key.is_a?(Integer)
  return default_variation if user.nil? || !user.is_a?(User) || !user.valid?

  workspace = @workspace_fetcher.fetch
  return default_variation if workspace.nil?

  experiment = workspace.get_experiment(experiment_key: experiment_key)
  return default_variation if experiment.nil?

  decision = @decider.decide(experiment: experiment, user: user)
  case decision
  when Decision::NotAllocated
    default_variation
  when Decision::ForcedAllocated
    decision.variation_key
  when Decision::NaturalAllocated
    exposure_event = UserEvent::Exposure.new(user: user, experiment: experiment, variation: decision.variation)
    @event_processor.process(event: exposure_event)
    decision.variation.key
  else
    default_variation
  end

rescue => e
  @logger.error { "Unexpected error while deciding variation for experiment[#{experiment_key}]. Returning default variation[#{default_variation}]: #{e.inspect}" }
  default_variation
end