Module: BrainzLab::Cortex

Defined in:
lib/brainzlab/cortex.rb,
lib/brainzlab/cortex/cache.rb,
lib/brainzlab/cortex/client.rb,
lib/brainzlab/cortex/provisioner.rb

Defined Under Namespace

Classes: Cache, Client, Provisioner

Class Method Summary collapse

Class Method Details

.all(**context) ⇒ Hash

Get all flags for a context

Examples:

flags = BrainzLab::Cortex.all(user: current_user)
flags[:new_checkout]  # => true
flags[:rate_limit]    # => 200

Parameters:

  • context (Hash) —

    Evaluation context

Returns:

  • (Hash) —

    All flag values



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# File 'lib/brainzlab/cortex.rb', line 93

def all(**context)
  return {} unless module_enabled?

  ensure_provisioned!
  return {} unless BrainzLab.configuration.cortex_valid?

  merged_context = merge_context(context)
  client.evaluate_all(context: merged_context)
end

.cache ⇒ Object 



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# File 'lib/brainzlab/cortex.rb', line 217

def cache
  @cache ||= Cache.new(BrainzLab.configuration.cortex_cache_ttl)
end

.clear_cache! ⇒ Object

Clear the flag cache



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# File 'lib/brainzlab/cortex.rb', line 173

def clear_cache!
  cache.clear!
end

.clear_context! ⇒ Object

Clear the current context



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# File 'lib/brainzlab/cortex.rb', line 186

def clear_context!
  Thread.current[:cortex_context] = nil
end

.client ⇒ Object 



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# File 'lib/brainzlab/cortex.rb', line 213

def client
  @client ||= Client.new(BrainzLab.configuration)
end

.create_flag(flag_name, name: nil, type: 'boolean', description: nil, tags: []) ⇒ Hash?

Create (push) a new feature flag definition.

Examples:

BrainzLab::Cortex.create_flag(:new_checkout, name: "New Checkout")

Parameters:

  • flag_name (String, Symbol) —

    flag key (lowercase, underscores)

  • name (String) (defaults to: nil) —

    human-readable name (defaults to the key)

  • type (String) (defaults to: 'boolean') —

    boolean | percentage | variant | segment

Returns:

  • (Hash, nil) —

    the created flag, or nil if disabled/unconfigured



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# File 'lib/brainzlab/cortex.rb', line 136

def create_flag(flag_name, name: nil, type: 'boolean', description: nil, tags: [])
  return nil unless writable?

  client.create_flag(
    key: flag_name.to_s,
    name: name || flag_name.to_s,
    flag_type: type,
    description: description,
    tags: tags
  )
end

.disable!(flag_name, environment: nil) ⇒ Object

Disable a flag in an environment (idempotent).



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# File 'lib/brainzlab/cortex.rb', line 155

def disable!(flag_name, environment: nil)
  set_enabled(flag_name, false, environment: environment)
end

.disabled?(flag_name, **context) ⇒ Boolean

Check if a feature flag is disabled

Parameters:

  • flag_name (String, Symbol) —

    The flag name

  • context (Hash) —

    Evaluation context

Returns:

  • (Boolean) —

    True if the flag is disabled



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# File 'lib/brainzlab/cortex.rb', line 29

def disabled?(flag_name, **context)
  !enabled?(flag_name, **context)
end

.enable!(flag_name, environment: nil) ⇒ Hash?

Enable a flag in an environment (idempotent).

Returns:

  • (Hash, nil) —

    the new state, or nil if disabled/unconfigured



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# File 'lib/brainzlab/cortex.rb', line 150

def enable!(flag_name, environment: nil)
  set_enabled(flag_name, true, environment: environment)
end

.enabled?(flag_name, **context) ⇒ Boolean

Check if a feature flag is enabled

Examples:

if BrainzLab::Cortex.enabled?(:new_checkout, user: current_user)
  render_new_checkout
end

Parameters:

  • flag_name (String, Symbol) —

    The flag name

  • context (Hash) —

    Evaluation context (user, attributes, etc.)

Returns:

  • (Boolean) —

    True if the flag is enabled



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# File 'lib/brainzlab/cortex.rb', line 20

def enabled?(flag_name, **context)
  result = get(flag_name, **context)
  [true, 'true'].include?(result)
end

.ensure_provisioned! ⇒ Object

INTERNAL ===



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# File 'lib/brainzlab/cortex.rb', line 202

def ensure_provisioned!
  return if @provisioned

  @provisioned = true
  provisioner.ensure_project!
end

.flag_config(flag_name) ⇒ Hash?

Get a flag’s configuration

Parameters:

  • flag_name (String, Symbol) —

    The flag name

Returns:

  • (Hash, nil) —

    Flag configuration



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# File 'lib/brainzlab/cortex.rb', line 117

def flag_config(flag_name)
  return nil unless module_enabled?

  ensure_provisioned!
  return nil unless BrainzLab.configuration.cortex_valid?

  client.get_flag(flag_name.to_s)
end

.get(flag_name, default: nil, **context) ⇒ Object

Get the value of a feature flag

Examples:

limit = BrainzLab::Cortex.get(:rate_limit, user: current_user, default: 100)

Parameters:

  • flag_name (String, Symbol) —

    The flag name

  • context (Hash) —

    Evaluation context

  • default (Object) (defaults to: nil) —

    Default value if flag not found

Returns:

  • (Object) —

    The flag value



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# File 'lib/brainzlab/cortex.rb', line 42

def get(flag_name, default: nil, **context)
  return default unless module_enabled?

  ensure_provisioned!
  return default unless BrainzLab.configuration.cortex_valid?

  flag_key = flag_name.to_s
  merged_context = merge_context(context)
  cache_key = build_cache_key(flag_key, merged_context)

  # Check cache first
  return cache.get(cache_key) if BrainzLab.configuration.cortex_cache_enabled && cache.has?(cache_key)

  result = client.evaluate(flag_key, context: merged_context)

  if result.nil?
    default
  else
    cache.set(cache_key, result) if BrainzLab.configuration.cortex_cache_enabled
    result
  end
end

.list_flags ⇒ Array<Hash>

List all flag definitions

Returns:

  • (Array<Hash>) —

    List of flag metadata



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# File 'lib/brainzlab/cortex.rb', line 105

def list_flags
  return [] unless module_enabled?

  ensure_provisioned!
  return [] unless BrainzLab.configuration.cortex_valid?

  client.list
end

.provisioner ⇒ Object 



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# File 'lib/brainzlab/cortex.rb', line 209

def provisioner
  @provisioner ||= Provisioner.new(BrainzLab.configuration)
end

.reset! ⇒ Object 



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# File 'lib/brainzlab/cortex.rb', line 221

def reset!
  @client = nil
  @provisioner = nil
  @cache = nil
  @provisioned = false
  Thread.current[:cortex_context] = nil
end

.set_context(**context) ⇒ Object

Set default context for all evaluations in current request

Parameters:

  • context (Hash) —

    Context to merge



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# File 'lib/brainzlab/cortex.rb', line 181

def set_context(**context)
  Thread.current[:cortex_context] = (Thread.current[:cortex_context] || {}).merge(context)
end

.set_percentage(flag_name, percentage, environment: nil) ⇒ Object

Set the rollout percentage (0-100) for a percentage flag.



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# File 'lib/brainzlab/cortex.rb', line 160

def set_percentage(flag_name, percentage, environment: nil)
  return nil unless writable?

  result = client.set_percentage(
    flag_name.to_s,
    percentage: percentage,
    environment: environment || BrainzLab.configuration.environment
  )
  clear_cache!
  result
end

.variant(flag_name, default: nil, **context) ⇒ String?

Get the variant for an A/B test flag

Examples:

variant = BrainzLab::Cortex.variant(:checkout_experiment, user: current_user)
case variant
when "control" then render_control
when "treatment_a" then render_treatment_a
when "treatment_b" then render_treatment_b
end

Parameters:

  • flag_name (String, Symbol) —

    The flag name

  • context (Hash) —

    Evaluation context

  • default (String) (defaults to: nil) —

    Default variant if flag not found

Returns:

  • (String, nil) —

    The variant name



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# File 'lib/brainzlab/cortex.rb', line 79

def variant(flag_name, default: nil, **context)
  result = get(flag_name, **context)
  result.is_a?(String) ? result : default
end

.with_context(**context) ⇒ Object

Evaluate flags with a temporary context

Parameters:

  • context (Hash) —

    Temporary context



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# File 'lib/brainzlab/cortex.rb', line 192

def with_context(**context)
  previous = Thread.current[:cortex_context]
  Thread.current[:cortex_context] = (previous || {}).merge(context)
  yield
ensure
  Thread.current[:cortex_context] = previous
end