Merge pull request #782 from celluloid/merge-supervision

Merge 'celluloid-supervision' back into the tree

.rubocop.yml

@@ -1,10 +1,14 @@
 AllCops:
   DisplayCopNames: true
+  TargetRubyVersion: 2.2.6
 
 #
 # Lint
 #
 
+Lint/AmbiguousBlockAssociation:
+  Enabled: false # TODO: enable
+
 Lint/AssignmentInCondition:
   Enabled: false # TODO: enable
 
@@ -24,7 +28,10 @@ Lint/RescueException:
   Enabled: false # TODO: explicitly mark cases where we want to rescue Exception
 
 Lint/ShadowedException:
-  Enabled: false # TODO; enable
+  Enabled: false # TODO: enable
+
+Lint/UnderscorePrefixedVariableName:
+  Enabled: false # TODO: enable
 
 Lint/UselessAssignment:
   Enabled: false # TODO: enable
@@ -51,7 +58,7 @@ Metrics/CyclomaticComplexity:
   Enabled: false # TODO: enable
 
 Metrics/LineLength:
-  Max: 200 # TODO: decrease
+  Max: 128 # TODO: decrease
 
 Metrics/MethodLength:
   Max: 100
@@ -66,12 +73,32 @@ Metrics/PerceivedComplexity:
   Enabled: false # TODO: enable
 
 #
-# Style
+# Naming
+#
+
+Naming/AccessorMethodName:
+  Enabled: false # TODO: enable
+
+Naming/MemoizedInstanceVariableName:
+  Enabled: false # TODO: enable
+
+Naming/UncommunicativeMethodParamName:
+  Enabled: false # TODO: enable(?)
+
+#
+# Performance
 #
 
-Style/AccessorMethodName:
+Performance/TimesMap:
   Enabled: false # TODO: enable
 
+#
+# Style
+#
+
+Style/AccessModifierDeclarations:
+  Enabled: false # TODO: enable(?)
+
 Style/CaseEquality:
   Enabled: false
 
@@ -81,6 +108,9 @@ Style/ClassAndModuleChildren:
 Style/ClassVars:
   Enabled: false # TODO: enable
 
+Style/CommentedKeyword:
+  Enabled: false # TODO: enable
+
 Style/Documentation:
   Enabled: false # TODO: enable
 
@@ -90,6 +120,9 @@ Style/DoubleNegation:
 Style/For:
   Enabled: false # TODO: enable
 
+Style/FormatStringToken:
+  Enabled: false # TODO: enable
+
 Style/FrozenStringLiteralComment:
   Enabled: false # TODO: enable
 
@@ -99,7 +132,10 @@ Style/GuardClause:
 Style/IfInsideElse:
   Enabled: false # TODO: enable
 
-Style/MethodMissing:
+Style/MethodMissingSuper:
+  Enabled: false # TODO: enable
+
+Style/MissingRespondToMissing:
   Enabled: false # TODO: enable
 
 Style/ModuleFunction:
@@ -114,6 +150,9 @@ Style/RegexpLiteral:
 Style/RescueModifier:
   Enabled: false # TODO: enable
 
+Style/RescueStandardError:
+  Enabled: false # TODO: enable
+
 Style/SafeNavigation:
   Enabled: false
 

Gemfile

@@ -7,11 +7,11 @@ group :development do
 end
 
 group :test do
+  gem "benchmark-ips",           require: false
+  gem "coveralls",   ">= 0.8",   require: false
   gem "rspec",       "~> 3",     require: false
   gem "rspec-retry", "~> 0.5",   require: false
-  gem "rubocop",     "= 0.45.0", require: false
-  gem "coveralls",   ">= 0.8",   require: false
-  gem "benchmark-ips",           require: false
+  gem "rubocop", "= 0.58.2", require: false
 end
 
 group :development, :test do

Guardfile

@@ -5,7 +5,7 @@ guard "rspec", cmd: "bundle exec rspec" do
   {
     "actor_examples" => "actor",
     "example_actor_class" => "actor",
-    "mailbox_examples" => %w(mailbox evented_mailbox),
+    "mailbox_examples" => %w[mailbox evented_mailbox],
     "task_examples" => ["tasks/task_fiber", "tasks/task_thread"]
   }.each do |examples, spec|
     watch("spec/support/#{examples}.rb") do

Rakefile

@@ -2,5 +2,5 @@ require "bundler/gem_tasks"
 
 Dir["tasks/**/*.rake"].each { |task| load task }
 
-task default: %w(spec rubocop)
-task ci: %w(default benchmark)
+task default: %w[spec rubocop]
+task ci: %w[default benchmark]

benchmarks/ring.rb

@@ -4,7 +4,7 @@
 require "bundler/setup"
 require "celluloid"
 require "benchmark/ips"
-require File.expand_path("../../examples/ring", __FILE__)
+require File.expand_path("../examples/ring", __dir__)
 
 # 512-node ring
 ring = Ring.new 512

celluloid.gemspec

@@ -1,7 +1,6 @@
-# -*- encoding: utf-8 -*-
 # frozen_string_literal: true
 
-lib = File.expand_path("../lib", __FILE__)
+lib = File.expand_path("lib", __dir__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 require "celluloid/version"
 
@@ -34,6 +33,4 @@ Gem::Specification.new do |spec|
   spec.required_rubygems_version = ">= 2.0.0"
 
   spec.add_runtime_dependency "timers", "~> 4"
-  spec.add_runtime_dependency "celluloid-pool",        "~> 0.20"
-  spec.add_runtime_dependency "celluloid-supervision", "~> 0.20"
 end

examples/basic_usage.rb

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$LOAD_PATH.push File.expand_path("../../lib", __FILE__)
+$LOAD_PATH.push File.expand_path("../lib", __dir__)
 require "celluloid/autostart"
 
 class Counter

examples/configurations.rb

@@ -0,0 +1,78 @@
+require "celluloid/current"
+
+puts "Use Supervision::Configuration objects!"
+
+class Hello
+  include Celluloid
+
+  finalizer :ceasing
+
+  def initialize(to)
+    @to = to
+    puts "Created Hello #{@to}"
+  end
+
+  def ceasing
+    puts "Hello #{@to} go buhbye"
+  end
+end
+
+class FooBar
+  include Celluloid
+
+  finalizer :ceasing
+
+  def initialize(i = 0)
+    @i = i
+    puts "Created FooBar: #{@i}"
+  end
+
+  def ceasing
+    puts "FooBar FooBar: #{@i} go buhbye"
+  end
+end
+
+puts "\nInstantiated in bulk, using #deploy"
+
+config = Celluloid::Supervision::Configuration.define([
+                                                        { type: FooBar, as: :foobar },
+                                                        { type: Hello, as: :hello, args: ["World"] }
+                                                      ])
+
+config.deploy
+puts "...shut it down"
+config.shutdown
+
+puts "\nInstantiated in bulk, using .deploy"
+
+config = Celluloid::Supervision::Configuration.deploy([
+                                                        { type: FooBar, as: :foobar, args: [1] },
+                                                        { type: Hello, as: :hello, args: ["World"] }
+                                                      ])
+
+puts "...shut it down"
+config.shutdown
+
+puts "\nInstantiated two actors individually, using a local configuration object"
+
+config = Celluloid::Supervision::Configuration.new
+config.define type: FooBar, as: :foobar11, args: [11]
+config.define type: FooBar, as: :foobar33, args: [33]
+config.deploy
+
+puts "Instantiated another, which starts automatically."
+puts "... using the local configuration object"
+puts "... using a lazy loaded argument"
+config.add type: Hello, as: :hello, args: -> { "Spinning World" }
+
+config.shutdown
+
+puts "\nReuse our last configuration!"
+
+config.deploy
+puts "...shut it down"
+config.shutdown
+
+puts "Thinking for 4 seconds, and 4 seconds only."
+sleep 4
+puts "Use Supervision::Configuration objects. Really!"

examples/futures.rb

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$LOAD_PATH.push File.expand_path("../../lib", __FILE__)
+$LOAD_PATH.push File.expand_path("../lib", __dir__)
 require "celluloid/autostart"
 require "digest/sha2"
 

examples/ring.rb

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$LOAD_PATH.push File.expand_path("../../lib", __FILE__)
+$LOAD_PATH.push File.expand_path("../lib", __dir__)
 require "celluloid/autostart"
 
 class Ring

examples/simple_pmap.rb

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$LOAD_PATH.push File.expand_path("../../lib", __FILE__)
+$LOAD_PATH.push File.expand_path("../lib", __dir__)
 require "celluloid/autostart"
 
 module Enumerable

examples/stack.rb

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$LOAD_PATH.push File.expand_path("../../lib", __FILE__)
+$LOAD_PATH.push File.expand_path("../lib", __dir__)
 require "celluloid/autostart"
 
 # This example builds on basic_usage.rb to show two things about #async: the

examples/supervisors_and_registry.rb

@@ -0,0 +1,82 @@
+require "celluloid/autostart"
+
+class MyActor
+  include Celluloid
+  attr_reader :state
+
+  def initialize
+    @state = :clean
+  end
+
+  def broken_method
+    @state = :dirty
+    oh_crap_im_totally_broken
+  end
+end
+
+#
+# Using the Supervisor API directly
+#
+
+puts "*** Demonstrating using the Supervisor API directly"
+
+# Calling supervise directly returns the supervisor
+supervisor = MyActor.supervise
+
+# We can get to the current version of an actor by calling
+# Celluloid::Supervisor#actors. This prints ':clean'
+puts "We should be in a clean state now: #{supervisor.actors.first.state}"
+puts "Brace yourself for a crash message..."
+
+# If we call a method that crashes an actor, it will print out a debug message,
+# then restart an actor in a clean state
+begin
+  supervisor.actors.first.broken_method
+rescue NameError
+  puts "Uhoh, we crashed the actor..."
+end
+
+puts "The supervisor should automatically restart the actor"
+
+# By now we'll be back in a :clean state!
+begin
+  puts "We should now be in a clean state again: #{supervisor.actors.first.state}"
+rescue Celluloid::DeadActorError
+  # Perhaps we got ahold of the actor before the supervisor restarted it
+  retry
+end
+
+#
+# Using the Actor Registry
+# This is the preferred approach and will make using DCell easier
+#
+
+puts "*** Demonstrating using the actor registry"
+
+# We can give our actor a name and thus avoid interacting with the supervisor
+MyActor.supervise as: :my_actor
+
+# Same as above, just getting the actor from a different place
+puts "We should be in a clean state now: #{Celluloid::Actor[:my_actor].state}"
+puts "Brace yourself for a crash message..."
+
+# If we call a method that crashes an actor, it will print out a debug message,
+# then restart an actor in a clean state
+begin
+  Celluloid::Actor[:my_actor].broken_method
+rescue NameError
+  puts "Uhoh, we crashed the actor..."
+end
+
+puts "The supervisor should automatically restart the actor"
+
+# By now we'll be back in a :clean state!
+begin
+  puts "We should now be in a clean state again: #{Celluloid::Actor[:my_actor].state}"
+rescue Celluloid::DeadActorError
+  # Perhaps we got ahold of the actor before the supervisor restarted it
+  # Don't want to catch Celluloid::DeadActorError all over the place? If this
+  # code were in a supervised Celluloid::Actor itself, the supervisor would
+  # catch Celluloid::DeadActorError and automatically restart this actor
+  retry
+end

examples/timers.rb

@@ -1,6 +1,6 @@
 #!/usr/bin/env ruby
 
-$LOAD_PATH.push File.expand_path("../../lib", __FILE__)
+$LOAD_PATH.push File.expand_path("../lib", __dir__)
 require "celluloid/current"
 
 class TimerExample