Dynamically resolve rack.multithread/rack.multiprocess

History.md

@@ -11,6 +11,7 @@
   * Faster phased restart and worker timeout (#2220)
   * Added `state_permission` to config DSL to set state file permissions (#2238)
   * Added `Puma.stats_hash`, which returns a stats in Hash instead of a JSON string (#2086, #2253)
+  * `rack.multithread` and `rack.multiprocess` now dynamically resolved by `max_thread` and `workers` respectively (#2288)
 
 * Deprecations, Removals and Breaking API Changes
   * `--control` has been removed. Use `--control-url` (#1487)

lib/puma/binder.rb

@@ -6,14 +6,15 @@
 require 'puma/const'
 require 'puma/util'
 require 'puma/minissl/context_builder'
+require 'puma/configuration'
 
 module Puma
   class Binder
     include Puma::Const
 
     RACK_VERSION = [1,6].freeze
 
-    def initialize(events)
+    def initialize(events, conf = Configuration.new)
       @events = events
       @listeners = []
       @inherited_fds = {}
@@ -23,8 +24,8 @@ def initialize(events)
       @proto_env = {
         "rack.version".freeze => RACK_VERSION,
         "rack.errors".freeze => events.stderr,
-        "rack.multithread".freeze => true,
-        "rack.multiprocess".freeze => false,
+        "rack.multithread".freeze => conf.options[:max_threads] > 1,
+        "rack.multiprocess".freeze => conf.options[:workers] >= 1,
         "rack.run_once".freeze => false,
         "SCRIPT_NAME".freeze => ENV['SCRIPT_NAME'] || "",
 

lib/puma/launcher.rb

@@ -47,7 +47,7 @@ def initialize(conf, launcher_args={})
       @original_argv = @argv.dup
       @config        = conf
 
-      @binder        = Binder.new(@events)
+      @binder        = Binder.new(@events, conf)
       @binder.create_inherited_fds(ENV).each { |k| ENV.delete k }
       @binder.create_activated_fds(ENV).each { |k| ENV.delete k }
 

test/test_binder.rb

@@ -6,6 +6,7 @@
 require "puma/binder"
 require "puma/puma_http11"
 require "puma/events"
+require "puma/configuration"
 
 class TestBinderBase < Minitest::Test
   include SSLHelper
@@ -295,6 +296,34 @@ def test_socket_activation_unix
     File.unlink(path) rescue nil # JRuby race?
   end
 
+  def test_rack_multithread_default_configuration
+    binder = Puma::Binder.new(@events)
+
+    assert binder.proto_env["rack.multithread"]
+  end
+
+  def test_rack_multithread_custom_configuration
+    conf = Puma::Configuration.new(max_threads: 1)
+
+    binder = Puma::Binder.new(@events, conf)
+
+    refute binder.proto_env["rack.multithread"]
+  end
+
+  def test_rack_multiprocess_default_configuration
+    binder = Puma::Binder.new(@events)
+
+    refute binder.proto_env["rack.multiprocess"]
+  end
+
+  def test_rack_multiprocess_custom_configuration
+    conf = Puma::Configuration.new(workers: 1)
+
+    binder = Puma::Binder.new(@events, conf)
+
+    assert binder.proto_env["rack.multiprocess"]
+  end
+
   private
 
   def assert_activates_sockets(path: nil, port: nil, url: nil, sock: nil)