Class: Featurevisor::Instance

Inherits:
Object
  • Object
show all
Defined in:
lib/featurevisor/instance.rb

Overview

Instance class for managing feature flag evaluations

Constant Summary collapse

EMPTY_DATAFILE =

Empty datafile template

{
  schemaVersion: "2",
  revision: "unknown",
  segments: {},
  features: {}
}.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ Instance

Initialize a new Featurevisor instance

Parameters:

  • options (Hash) (defaults to: {}) —

    Instance options

Options Hash (options):

  • :datafile (Hash, String) —

    Datafile content or JSON string

  • :context (Hash) —

    Initial context

  • :log_level (String) —

    Log level

  • :logger (Logger) —

    Logger instance

  • :sticky (Hash) —

    Sticky features

  • :hooks (Array<Hook>) —

    Array of hooks



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# File 'lib/featurevisor/instance.rb', line 26

def initialize(options = {})
  # from options
  @context = options[:context] || {}
  @logger = options[:logger] || Featurevisor.create_logger(level: options[:log_level] || "info")
  @hooks_manager = Featurevisor::Hooks::HooksManager.new(
    hooks: (options[:hooks] || []).map { |hook_data| Featurevisor::Hooks::Hook.new(hook_data) },
    logger: @logger
  )
  @emitter = Featurevisor::Emitter.new
  @sticky = options[:sticky] || {}

  # datafile
  @datafile_reader = Featurevisor::DatafileReader.new(
    datafile: EMPTY_DATAFILE,
    logger: @logger
  )

  if options[:datafile]
    @datafile_reader = Featurevisor::DatafileReader.new(
      datafile: options[:datafile].is_a?(String) ? JSON.parse(options[:datafile], symbolize_names: true) : options[:datafile],
      logger: @logger
    )
  end

  @logger.info("Featurevisor SDK initialized")
end

Instance Attribute Details

#context ⇒ Object (readonly)

Returns the value of attribute context.



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# File 'lib/featurevisor/instance.rb', line 8

def context
  @context
end

#datafile_reader ⇒ Object (readonly)

Returns the value of attribute datafile_reader.



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# File 'lib/featurevisor/instance.rb', line 8

def datafile_reader
  @datafile_reader
end

#emitter ⇒ Object (readonly)

Returns the value of attribute emitter.



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# File 'lib/featurevisor/instance.rb', line 8

def emitter
  @emitter
end

#hooks_manager ⇒ Object (readonly)

Returns the value of attribute hooks_manager.



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# File 'lib/featurevisor/instance.rb', line 8

def hooks_manager
  @hooks_manager
end

#logger ⇒ Object (readonly)

Returns the value of attribute logger.



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# File 'lib/featurevisor/instance.rb', line 8

def logger
  @logger
end

#sticky ⇒ Object (readonly)

Returns the value of attribute sticky.



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# File 'lib/featurevisor/instance.rb', line 8

def sticky
  @sticky
end

Instance Method Details

#add_hook(hook) ⇒ Proc?

Add a hook

Parameters:

  • hook (Hook) —

    Hook to add

Returns:

  • (Proc, nil) —

    Remove function or nil if hook already exists



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# File 'lib/featurevisor/instance.rb', line 115

def add_hook(hook)
  @hooks_manager.add(hook)
end

#close ⇒ Object

Close the instance



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# File 'lib/featurevisor/instance.rb', line 128

def close
  @emitter.clear_all
end

#evaluate_flag(feature_key, context = {}, options = {}) ⇒ Hash

Evaluate a flag

Parameters:

  • feature_key (String) —

    Feature key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Hash) —

    Evaluation result



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# File 'lib/featurevisor/instance.rb', line 184

def evaluate_flag(feature_key, context = {}, options = {})
  Featurevisor::Evaluate.evaluate_with_hooks(
    get_evaluation_dependencies(context, options).merge(
      type: "flag",
      feature_key: feature_key
    )
  )
end

#evaluate_variable(feature_key, variable_key, context = {}, options = {}) ⇒ Hash

Evaluate a variable

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Hash) —

    Evaluation result



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# File 'lib/featurevisor/instance.rb', line 250

def evaluate_variable(feature_key, variable_key, context = {}, options = {})
  Featurevisor::Evaluate.evaluate_with_hooks(
    get_evaluation_dependencies(context, options).merge(
      type: "variable",
      feature_key: feature_key,
      variable_key: variable_key
    )
  )
end

#evaluate_variation(feature_key, context = {}, options = {}) ⇒ Hash

Evaluate a variation

Parameters:

  • feature_key (String) —

    Feature key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Hash) —

    Evaluation result



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# File 'lib/featurevisor/instance.rb', line 213

def evaluate_variation(feature_key, context = {}, options = {})
  Featurevisor::Evaluate.evaluate_with_hooks(
    get_evaluation_dependencies(context, options).merge(
      type: "variation",
      feature_key: feature_key
    )
  )
end

#get_all_evaluations(context = {}, feature_keys = [], options = {}) ⇒ Hash

Get all evaluations

Parameters:

  • context (Hash) (defaults to: {}) —

    Context

  • feature_keys (Array<String>) (defaults to: []) —

    Feature keys to evaluate

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Hash) —

    All evaluations



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# File 'lib/featurevisor/instance.rb', line 369

def get_all_evaluations(context = {}, feature_keys = [], options = {})
  result = {}

          keys = feature_keys.size > 0 ? feature_keys : @datafile_reader.get_feature_keys

  keys.each do |feature_key|
    # Convert symbol keys to strings for evaluation functions
    feature_key_str = feature_key.to_s

    # isEnabled
    evaluated_feature = {
      enabled: is_enabled(feature_key_str, context, options)
    }

    # variation
    if @datafile_reader.has_variations?(feature_key_str)
      variation = get_variation(feature_key_str, context, options)
      evaluated_feature[:variation] = variation if variation
    end

    # variables
    variable_keys = @datafile_reader.get_variable_keys(feature_key_str)
    if variable_keys.size > 0
      evaluated_feature[:variables] = {}

      variable_keys.each do |variable_key|
        evaluated_feature[:variables][variable_key] = get_variable(
          feature_key_str,
          variable_key,
          context,
          options
        )
      end
    end

    result[feature_key] = evaluated_feature
  end

  result
end

#get_context(context = nil) ⇒ Hash

Get context

Parameters:

  • context (Hash, nil) (defaults to: nil) —

    Additional context to merge

Returns:

  • (Hash) —

    Merged context



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# File 'lib/featurevisor/instance.rb', line 156

def get_context(context = nil)
  if context
    {
      **@context,
      **context
    }
  else
    @context
  end
end

#get_feature(feature_key) ⇒ Hash?

Get a feature by key

Parameters:

  • feature_key (String) —

    Feature key

Returns:

  • (Hash, nil) —

    Feature data or nil if not found



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# File 'lib/featurevisor/instance.rb', line 108

def get_feature(feature_key)
  @datafile_reader.get_feature(feature_key)
end

#get_revision ⇒ String

Get the revision

Returns:

  • (String) —

    Revision string



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# File 'lib/featurevisor/instance.rb', line 101

def get_revision
  @datafile_reader.get_revision
end

#get_variable(feature_key, variable_key, context = {}, options = {}) ⇒ Object?

Get variable value

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Object, nil) —

    Variable value or nil



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# File 'lib/featurevisor/instance.rb', line 266

def get_variable(feature_key, variable_key, context = {}, options = {})
  begin
    evaluation = evaluate_variable(feature_key, variable_key, context, options)

    if !evaluation[:variable_value].nil?
      if evaluation[:variable_schema] &&
         evaluation[:variable_schema][:type] == "json" &&
         evaluation[:variable_value].is_a?(String)
        JSON.parse(evaluation[:variable_value], symbolize_names: true)
      else
        evaluation[:variable_value]
      end
    else
      nil
    end
  rescue => e
    @logger.error("getVariable", { feature_key: feature_key, variable_key: variable_key, error: e })
    nil
  end
end

#get_variable_array(feature_key, variable_key, context = {}, options = {}) ⇒ Array?

Get variable as array

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Array, nil) —

    Array value or nil



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# File 'lib/featurevisor/instance.rb', line 337

def get_variable_array(feature_key, variable_key, context = {}, options = {})
  variable_value = get_variable(feature_key, variable_key, context, options)
  get_value_by_type(variable_value, "array")
end

#get_variable_boolean(feature_key, variable_key, context = {}, options = {}) ⇒ Boolean?

Get variable as boolean

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Boolean, nil) —

    Boolean value or nil



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# File 'lib/featurevisor/instance.rb', line 293

def get_variable_boolean(feature_key, variable_key, context = {}, options = {})
  variable_value = get_variable(feature_key, variable_key, context, options)
  get_value_by_type(variable_value, "boolean")
end

#get_variable_double(feature_key, variable_key, context = {}, options = {}) ⇒ Float?

Get variable as double

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Float, nil) —

    Float value or nil



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# File 'lib/featurevisor/instance.rb', line 326

def get_variable_double(feature_key, variable_key, context = {}, options = {})
  variable_value = get_variable(feature_key, variable_key, context, options)
  get_value_by_type(variable_value, "double")
end

#get_variable_integer(feature_key, variable_key, context = {}, options = {}) ⇒ Integer?

Get variable as integer

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Integer, nil) —

    Integer value or nil



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# File 'lib/featurevisor/instance.rb', line 315

def get_variable_integer(feature_key, variable_key, context = {}, options = {})
  variable_value = get_variable(feature_key, variable_key, context, options)
  get_value_by_type(variable_value, "integer")
end

#get_variable_json(feature_key, variable_key, context = {}, options = {}) ⇒ Object?

Get variable as JSON

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Object, nil) —

    JSON value or nil



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# File 'lib/featurevisor/instance.rb', line 359

def get_variable_json(feature_key, variable_key, context = {}, options = {})
  variable_value = get_variable(feature_key, variable_key, context, options)
  get_value_by_type(variable_value, "json")
end

#get_variable_object(feature_key, variable_key, context = {}, options = {}) ⇒ Hash?

Get variable as object

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Hash, nil) —

    Object value or nil



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# File 'lib/featurevisor/instance.rb', line 348

def get_variable_object(feature_key, variable_key, context = {}, options = {})
  variable_value = get_variable(feature_key, variable_key, context, options)
  get_value_by_type(variable_value, "object")
end

#get_variable_string(feature_key, variable_key, context = {}, options = {}) ⇒ String?

Get variable as string

Parameters:

  • feature_key (String) —

    Feature key

  • variable_key (String) —

    Variable key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (String, nil) —

    String value or nil



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# File 'lib/featurevisor/instance.rb', line 304

def get_variable_string(feature_key, variable_key, context = {}, options = {})
  variable_value = get_variable(feature_key, variable_key, context, options)
  get_value_by_type(variable_value, "string")
end

#get_variation(feature_key, context = {}, options = {}) ⇒ String?

Get variation value

Parameters:

  • feature_key (String) —

    Feature key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (String, nil) —

    Variation value or nil



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# File 'lib/featurevisor/instance.rb', line 227

def get_variation(feature_key, context = {}, options = {})
  begin
    evaluation = evaluate_variation(feature_key, context, options)

    if evaluation[:variation_value]
      evaluation[:variation_value]
    elsif evaluation[:variation]
      evaluation[:variation][:value]
    else
      nil
    end
  rescue => e
    @logger.error("getVariation", { feature_key: feature_key, error: e })
    nil
  end
end

#is_enabled(feature_key, context = {}, options = {}) ⇒ Boolean

Check if a feature is enabled

Parameters:

  • feature_key (String) —

    Feature key

  • context (Hash) (defaults to: {}) —

    Context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:

  • (Boolean) —

    True if feature is enabled



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# File 'lib/featurevisor/instance.rb', line 198

def is_enabled(feature_key, context = {}, options = {})
  begin
    evaluation = evaluate_flag(feature_key, context, options)
    evaluation[:enabled] == true
  rescue => e
    @logger.error("isEnabled", { feature_key: feature_key, error: e })
    false
  end
end

#on(event_name, callback) ⇒ Proc

Subscribe to an event

Parameters:

  • event_name (String) —

    Event name

  • callback (Proc) —

    Callback function

Returns:

  • (Proc) —

    Unsubscribe function



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# File 'lib/featurevisor/instance.rb', line 123

def on(event_name, callback)
  @emitter.on(event_name, callback)
end

#set_context(context, replace = false) ⇒ Object

Set context

Parameters:

  • context (Hash) —

    Context to set

  • replace (Boolean) (defaults to: false) —

    Whether to replace existing context



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# File 'lib/featurevisor/instance.rb', line 135

def set_context(context, replace = false)
  if replace
    @context = context
  else
    @context = { **@context, **context }
  end

  @emitter.trigger("context_set", {
    context: @context,
    replaced: replace
  })

  @logger.debug(replace ? "context replaced" : "context updated", {
    context: @context,
    replaced: replace
  })
end

#set_datafile(datafile) ⇒ Object

Set the datafile

Parameters:

  • datafile (Hash, String) —

    Datafile content or JSON string



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# File 'lib/featurevisor/instance.rb', line 61

def set_datafile(datafile)
  begin
    new_datafile_reader = Featurevisor::DatafileReader.new(
      datafile: datafile.is_a?(String) ? JSON.parse(datafile, symbolize_names: true) : datafile,
      logger: @logger
    )

    details = Featurevisor::Events.get_params_for_datafile_set_event(@datafile_reader, new_datafile_reader)
    @datafile_reader = new_datafile_reader

    @logger.info("datafile set", details)
    @emitter.trigger("datafile_set", details)
  rescue => e
    @logger.error("could not parse datafile", { error: e })
  end
end

#set_log_level(level) ⇒ Object

Set the log level

Parameters:

  • level (String) —

    Log level



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# File 'lib/featurevisor/instance.rb', line 55

def set_log_level(level)
  @logger.set_level(level)
end

#set_sticky(sticky, replace = false) ⇒ Object

Set sticky features

Parameters:

  • sticky (Hash) —

    Sticky features

  • replace (Boolean) (defaults to: false) —

    Whether to replace existing sticky features



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# File 'lib/featurevisor/instance.rb', line 81

def set_sticky(sticky, replace = false)
  previous_sticky_features = @sticky || {}

  if replace
    @sticky = sticky
  else
    @sticky = {
      **@sticky,
      **sticky
    }
  end

  params = Featurevisor::Events.get_params_for_sticky_set_event(previous_sticky_features, @sticky, replace)

  @logger.info("sticky features set", params)
  @emitter.trigger("sticky_set", params)
end

#spawn(context = {}, options = {}) ⇒ ChildInstance

Spawn a child instance

Parameters:

  • context (Hash) (defaults to: {}) —

    Child context

  • options (Hash) (defaults to: {}) —

    Override options

Returns:



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# File 'lib/featurevisor/instance.rb', line 171

def spawn(context = {}, options = {})
  Featurevisor::ChildInstance.new(
    parent: self,
    context: get_context(context),
    sticky: options[:sticky]
  )
end