Merge pull request #23057 from schneems/schneems/default-puma-config

Add Default Puma Config

5 files changed, 64 insertions, 3 deletions

diff --git a/railties/lib/rails/generators/app_base.rb b/railties/lib/rails/generators/app_base.rb
index 51394de824..8bc7dd63f9 100644
--- a/railties/lib/rails/generators/app_base.rb
+++ b/railties/lib/rails/generators/app_base.rb
@@ -51,6 +51,9 @@ module Rails
         class_option :skip_active_record, type: :boolean, aliases: '-O', default: false,
                                           desc: 'Skip Active Record files'
 
+        class_option :skip_puma,          type: :boolean, aliases: '-P', default: false,
+                                          desc: 'Skip Puma related files'
+
         class_option :skip_action_cable,  type: :boolean, aliases: '-C', default: false,
                                           desc: 'Skip Action Cable files'
 
@@ -113,6 +116,7 @@ module Rails
       def gemfile_entries
         [rails_gemfile_entry,
          database_gemfile_entry,
+         webserver_gemfile_entry,
          assets_gemfile_entry,
          javascript_gemfile_entry,
          jbuilder_gemfile_entry,
@@ -171,6 +175,12 @@ module Rails
                             "Use #{options[:database]} as the database for Active Record"
       end
 
+      def webserver_gemfile_entry
+        return [] if options[:skip_puma]
+        comment = 'Use Puma as the app server'
+        GemfileEntry.new('puma', nil, comment)
+      end
+
       def include_all_railties?
         options.values_at(:skip_active_record, :skip_action_mailer, :skip_test, :skip_sprockets, :skip_action_cable).none?
       end
diff --git a/railties/lib/rails/generators/rails/app/app_generator.rb b/railties/lib/rails/generators/rails/app/app_generator.rb
index 775750d86b..248ad20019 100644
--- a/railties/lib/rails/generators/rails/app/app_generator.rb
+++ b/railties/lib/rails/generators/rails/app/app_generator.rb
@@ -79,6 +79,7 @@ module Rails
         template "environment.rb"
         template "secrets.yml"
         template "cable.yml" unless options[:skip_action_cable]
+        template "puma.rb"   unless options[:skip_puma]
 
         directory "environments"
         directory "initializers"
diff --git a/railties/lib/rails/generators/rails/app/templates/Gemfile b/railties/lib/rails/generators/rails/app/templates/Gemfile
index da5af4eefc..3825dc4e38 100644
--- a/railties/lib/rails/generators/rails/app/templates/Gemfile
+++ b/railties/lib/rails/generators/rails/app/templates/Gemfile
@@ -12,9 +12,6 @@ source 'https://rubygems.org'
 <% end -%>
 <% end -%>
 
-# Use Puma as the app server
-gem 'puma'
-
 # Use ActiveModel has_secure_password
 # gem 'bcrypt', '~> 3.1.7'
 
diff --git a/railties/lib/rails/generators/rails/app/templates/config/puma.rb b/railties/lib/rails/generators/rails/app/templates/config/puma.rb
new file mode 100644
index 0000000000..1bf274bc66
--- /dev/null
+++ b/railties/lib/rails/generators/rails/app/templates/config/puma.rb
@@ -0,0 +1,44 @@
+# Puma can serve each request in a thread from an internal thread pool.
+# The `threads` method setting takes two numbers a minimum and maximum.
+# Any libraries that use thread pools should be configured to match
+# the maximum value specified for Puma. Default is set to 5 threads for minimum
+# and maximum, this matches the default thread size of Active Record.
+#
+threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }.to_i
+threads threads_count, threads_count
+
+# Specifies the `port` that Puma will listen on to receive requests, default is 3000.
+#
+port        ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked webserver processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory. If you use this option
+# you need to make sure to reconnect any threads in the `on_worker_boot`
+# block.
+#
+# preload_app!
+
+# The code in the `on_worker_boot` will be called if you are using
+# clustered mode by specifying a number of `workers`. After each worker
+# process is booted this block will be run, if you are using `preload_app!`
+# option you will want to use this block to reconnect to any threads
+# or connections that may have been created at application boot, Ruby
+# cannot share connections between processes.
+#
+# on_worker_boot do
+#   ActiveRecord::Base.establish_connection if defined?(ActiveRecord)
+# end
diff --git a/railties/test/generators/app_generator_test.rb b/railties/test/generators/app_generator_test.rb
index 49536c068f..937f68fff8 100644
--- a/railties/test/generators/app_generator_test.rb
+++ b/railties/test/generators/app_generator_test.rb
@@ -27,6 +27,7 @@ DEFAULT_APP_FILES = %w(
   config/initializers
   config/locales
   config/cable.yml
+  config/puma.rb
   db
   lib
   lib/tasks
@@ -337,6 +338,14 @@ class AppGeneratorTest < Rails::Generators::TestCase
     end
   end
 
+  def test_generator_if_skip_puma_is_given
+    run_generator [destination_root, "--skip-puma"]
+    assert_no_file "config/puma.rb"
+    assert_file "Gemfile" do |content|
+      assert_no_match(/puma/, content)
+    end
+  end
+
   def test_generator_if_skip_active_record_is_given
     run_generator [destination_root, "--skip-active-record"]
     assert_no_file "config/database.yml"