docs: migration guide for v6

MigrationGuide.md

@@ -0,0 +1,39 @@
+# Migrating to Unleash-Client-Ruby 6.0.0
+
+The upgrade the v6.0.0 of the Unleash client should be mostly seamless. There are a few significant changes that may require some changes on the consumer side or that the consumer should be generally aware of.
+
+## Custom strategy changes
+
+There's a few changes to custom strategies that may affect you if you make heavy use of them.
+
+Firstly, custom strategies are no longer allowed to override the built in strategies, namely custom strategies named 'applicationHostname', 'default', 'flexibleRollout', 'gradualRolloutRandom', 'gradualRolloutSessionId', 'gradualRolloutUserId', 'remoteAddress' or 'userWithId' will now raise an error on startup, whereas previously creating a custom strategy with one of these names would raise a warning in the logs.
+
+Secondly, the deprecated `register_custom_strategies` method has now been removed. The only way to register a custom strategy is to use configuration, i.e.
+
+```ruby
+class MyCustomStrategy
+  def name
+    'myCustomStrategy'
+  end
+
+  def is_enabled?(params = {}, context = nil)
+    true
+  end
+end
+
+Unleash.configure do |config|
+  config.strategies.add(MyCustomStrategy.new)
+end
+```
+
+If you're already using configuration to register your custom strategies and you're not overriding the default strategies, this section doesn't affect you.
+
+## Direct access to strategy objects
+
+The objects for base strategies are no longer directly accessible via the SDK, the `known_strategies` method will only return custom strategies registered by the user. If you need to know whether or not a custom strategy will override either a built in or custom strategy, the `includes?` method will return a false if the name is available.
+
+Generally, it's strongly discouraged to access or alter any of the strategy properties other than the name for built in strategies. v.6.0.0 makes this a hard requirement.
+
+## ARM requirements
+
+v6.0.0 has a new dependency on a native binary; we currently only distribute ARM binaries for MacOS. If you need ARM support on Linux or Windows, please feel free to open an issue.

README.md

@@ -32,6 +32,10 @@ Ruby client for the [Unleash](https://github.com/Unleash/unleash) feature manage
 - [Releasing](#releasing)
 - [Contributing](#contributing)
 
+# Migrating to v6
+
+If you're using custom strategies or overriding built in strategies, please read the full [migration guide](./MigrationGuide.md) before upgrading to v6.
+
 ## Supported Ruby Interpreters
 
 - MRI 3.3

lib/unleash.rb

@@ -10,7 +10,7 @@ module Unleash
   TIME_RESOLUTION = 3
 
   class << self
-    attr_accessor :configuration, :toggle_fetcher, :toggles, :toggle_metrics, :reporter, :segment_cache, :logger
+    attr_accessor :configuration, :toggle_fetcher, :reporter, :logger, :engine
   end
 
   self.configuration = Unleash::Configuration.new

lib/unleash/client.rb

@@ -2,7 +2,7 @@
 require 'unleash/toggle_fetcher'
 require 'unleash/metrics_reporter'
 require 'unleash/scheduled_executor'
-require 'unleash/feature_toggle'
+require 'unleash/variant'
 require 'unleash/util/http'
 require 'logger'
 require 'time'
@@ -11,14 +11,17 @@ module Unleash
   class Client
     attr_accessor :fetcher_scheduled_executor, :metrics_scheduled_executor
 
+    # rubocop:disable Metrics/AbcSize
     def initialize(*opts)
       Unleash.configuration = Unleash::Configuration.new(*opts) unless opts.empty?
       Unleash.configuration.validate!
 
       Unleash.logger = Unleash.configuration.logger.clone
       Unleash.logger.level = Unleash.configuration.log_level
+      Unleash.engine = YggdrasilEngine.new
+      Unleash.engine.register_custom_strategies(Unleash.configuration.strategies.custom_strategies)
 
-      Unleash.toggle_fetcher = Unleash::ToggleFetcher.new
+      Unleash.toggle_fetcher = Unleash::ToggleFetcher.new Unleash.engine
       if Unleash.configuration.disable_client
         Unleash.logger.warn "Unleash::Client is disabled! Will only return default (or bootstrapped if available) results!"
         Unleash.logger.warn "Unleash::Client is disabled! Metrics and MetricsReporter are also disabled!"
@@ -30,6 +33,7 @@ def initialize(*opts)
       start_toggle_fetcher
       start_metrics unless Unleash.configuration.disable_metrics
     end
+    # rubocop:enable Metrics/AbcSize
 
     def is_enabled?(feature, context = nil, default_value_param = false, &fallback_blk)
       Unleash.logger.debug "Unleash::Client.is_enabled? feature: #{feature} with context #{context}"
@@ -40,15 +44,16 @@ def is_enabled?(feature, context = nil, default_value_param = false, &fallback_b
                         default_value_param
                       end
 
-      toggle_as_hash = Unleash&.toggles&.select{ |toggle| toggle['name'] == feature }&.first
-      if toggle_as_hash.nil?
+      toggle_enabled = Unleash.engine.enabled?(feature, context)
+      if toggle_enabled.nil?
         Unleash.logger.debug "Unleash::Client.is_enabled? feature: #{feature} not found"
+        Unleash.engine.count_toggle(feature, false)
         return default_value
       end
 
-      toggle = Unleash::FeatureToggle.new(toggle_as_hash, Unleash&.segment_cache)
+      Unleash.engine.count_toggle(feature, toggle_enabled)
 
-      toggle.is_enabled?(context)
+      toggle_enabled
     end
 
     def is_disabled?(feature, context = nil, default_value_param = true, &fallback_blk)
@@ -71,23 +76,19 @@ def if_disabled(feature, context = nil, default_value = true, &blk)
     end
 
     def get_variant(feature, context = Unleash::Context.new, fallback_variant = disabled_variant)
-      Unleash.logger.debug "Unleash::Client.get_variant for feature: #{feature} with context #{context}"
-
-      toggle_as_hash = Unleash&.toggles&.select{ |toggle| toggle['name'] == feature }&.first
-
-      if toggle_as_hash.nil?
-        Unleash.logger.debug "Unleash::Client.get_variant feature: #{feature} not found"
-        return fallback_variant
-      end
-
-      toggle = Unleash::FeatureToggle.new(toggle_as_hash, Unleash&.segment_cache)
-      variant = toggle.get_variant(context, fallback_variant)
+      variant = Unleash.engine.get_variant(feature, context)
 
       if variant.nil?
         Unleash.logger.debug "Unleash::Client.get_variant variants for feature: #{feature} not found"
+        Unleash.engine.count_toggle(feature, false)
         return fallback_variant
       end
 
+      variant = Variant.new(variant)
+
+      Unleash.engine.count_variant(feature, variant.name)
+      Unleash.engine.count_toggle(feature, variant.feature_enabled)
+
       # TODO: Add to README: name, payload, enabled (bool)
 
       variant
@@ -96,7 +97,6 @@ def get_variant(feature, context = Unleash::Context.new, fallback_variant = disa
     # safe shutdown: also flush metrics to server and toggles to disk
     def shutdown
       unless Unleash.configuration.disable_client
-        Unleash.toggle_fetcher.save!
         Unleash.reporter.post unless Unleash.configuration.disable_metrics
         shutdown!
       end
@@ -117,7 +117,7 @@ def info
         'appName': Unleash.configuration.app_name,
         'instanceId': Unleash.configuration.instance_id,
         'sdkVersion': "unleash-client-ruby:" + Unleash::VERSION,
-        'strategies': Unleash.strategies.keys,
+        'strategies': Unleash.strategies.known_strategies,
         'started': Time.now.iso8601(Unleash::TIME_RESOLUTION),
         'interval': Unleash.configuration.metrics_interval_in_millis,
         'platformName': RUBY_ENGINE,
@@ -140,7 +140,6 @@ def start_toggle_fetcher
     end
 
     def start_metrics
-      Unleash.toggle_metrics = Unleash::Metrics.new
       Unleash.reporter = Unleash::MetricsReporter.new
       self.metrics_scheduled_executor = Unleash::ScheduledExecutor.new(
         'MetricsReporter',
@@ -166,7 +165,7 @@ def register
     end
 
     def disabled_variant
-      @disabled_variant ||= Unleash::FeatureToggle.disabled_variant
+      @disabled_variant ||= Unleash::Variant.disabled_variant
     end
 
     def first_fetch_is_eager

lib/unleash/configuration.rb

@@ -40,9 +40,9 @@ def metrics_interval_in_millis
     def validate!
       return if self.disable_client
 
-      raise ArgumentError, "URL and app_name are required parameters." if self.app_name.nil? || self.url.nil?
+      raise ArgumentError, "app_name is a required parameter." if self.app_name.nil?
 
-      validate_custom_http_headers!(self.custom_http_headers)
+      validate_custom_http_headers!(self.custom_http_headers) unless self.url.nil?
     end
 
     def refresh_backup_file!