Allow to define a custom formatter for logs

History.md

@@ -1,7 +1,7 @@
 ## Master
 
 * Features
-  * Your feature goes here (#Github Number)
+  * Add log_formatter configuration (#1816)
 
 * Bugfixes
   * Your bugfix goes here (#Github Number)
@@ -11,8 +11,7 @@
 * 2 bugfixes
   * Fix socket removed after reload - should fix problems with systemd socket activation. (#1829)
   * Add extconf tests for DTLS_method & TLS_server_method, use in minissl.rb. Should fix "undefined symbol: DTLS_method" when compiling against old OpenSSL versions. (#1832)
-* 1 other
-  * Removed unnecessary RUBY_VERSION checks. (#1827)
+
 
 ## 4.0.0 / 2019-06-25
 

lib/puma/dsl.rb

@@ -282,6 +282,10 @@ def stdout_redirect(stdout=nil, stderr=nil, append=false)
       @options[:redirect_append] = append
     end
 
+    def log_formatter(&block)
+      @options[:log_formatter] = block
+    end
+
     # Configure +min+ to be the minimum number of threads to use to answer
     # requests and +max+ the maximum.
     #

lib/puma/events.rb

@@ -23,6 +23,16 @@ def call(str)
       end
     end
 
+    class CustomFormatter
+      def initialize(formatter)
+        @formatter = formatter
+      end
+
+      def call(str)
+        @formatter.call(str)
+      end
+    end
+
     include Const
 
     # Create an Events object that prints to +stdout+ and +stderr+.

lib/puma/launcher.rb

@@ -50,9 +50,6 @@ def initialize(conf, launcher_args={})
       @original_argv = @argv.dup
       @config        = conf
 
-      @binder        = Binder.new(@events)
-      @binder.import_from_env
-
       @environment = conf.environment
 
       # Advertise the Configuration
@@ -63,6 +60,11 @@ def initialize(conf, launcher_args={})
       @options = @config.options
       @config.clamp
 
+      @events.formatter = Events::CustomFormatter.new(@options[:log_formatter]) if @options[:log_formatter]
+
+      @binder        = Binder.new(@events)
+      @binder.import_from_env
+
       generate_restart_data
 
       if clustered? && !Process.respond_to?(:fork)
@@ -81,7 +83,7 @@ def initialize(conf, launcher_args={})
       set_rack_environment
 
       if clustered?
-        @events.formatter = Events::PidFormatter.new
+        @events.formatter = Events::PidFormatter.new unless @options[:log_formatter]
         @options[:logger] = @events
 
         @runner = Cluster.new(self, @events)

test/config/custom_log_formatter.rb

@@ -0,0 +1,3 @@
+log_formatter do |str|
+  "[#{Process.pid}] [#{Socket.gethostname}] #{Time.now}: #{str}"
+end

test/test_cli.rb

@@ -253,6 +253,30 @@ def test_state_file_callback_filtering
     assert_empty keys_not_stripped
   end
 
+  def test_log_formatter_default_single
+    cli = Puma::CLI.new [ ]
+    assert_instance_of Puma::Events::DefaultFormatter, cli.launcher.events.formatter
+  end
+
+  def test_log_formatter_default_clustered
+    skip_on :jruby, :windows
+
+    cli = Puma::CLI.new [ "-w 2" ]
+    assert_instance_of Puma::Events::PidFormatter, cli.launcher.events.formatter
+  end
+
+  def test_log_formatter_custom_single
+    cli = Puma::CLI.new [ "--config", "test/config/custom_log_formatter.rb" ]
+    assert_instance_of Puma::Events::CustomFormatter, cli.launcher.events.formatter
+  end
+
+  def test_log_formatter_custom_clustered
+    skip_on :jruby, :windows
+
+    cli = Puma::CLI.new [ "--config", "test/config/custom_log_formatter.rb", "-w 2" ]
+    assert_instance_of Puma::Events::CustomFormatter, cli.launcher.events.formatter
+  end
+
   def test_state
     url = "tcp://127.0.0.1:#{next_port}"
     cli = Puma::CLI.new ["--state", @tmp_path, "--control", url]

test/test_events.rb

@@ -152,7 +152,7 @@ def test_pid_formatter
   end
 
   def test_custom_log_formatter
-    custom_formatter = proc { |str| "-> #{ str }" }
+    custom_formatter = Puma::Events::CustomFormatter.new(Proc.new { |str| "-> #{str}" })
 
     out, _ = capture_io do
       events = Puma::Events.stdio