Add ability to specify custom logger (#2725)

* Add ability to specify custom logger

* Add test

* Use regex match

lib/puma/dsl.rb

@@ -365,6 +365,11 @@ def log_requests(which=true)
       @options[:log_requests] = which
     end
 
+    # Pass in a custom logging class instance
+    def logger(custom_logger)
+      @options[:logger] = custom_logger
+    end
+
     # Show debugging info
     #
     def debug

test/config/custom_logger.rb

@@ -0,0 +1,13 @@
+class CustomLogger
+  def initialize(output=STDOUT)
+    @output = output
+  end
+
+  def write(msg)
+    @output.print 'Custom logging: ' + msg
+    @output.flush
+  end
+end
+
+log_requests
+logger CustomLogger.new(STDOUT)

test/test_config.rb

@@ -59,6 +59,19 @@ def test_ssl_configuration_from_DSL
     assert_equal [200, {}, ["embedded app"]], app.call({})
   end
 
+  def test_custom_logger_from_DSL
+    conf = Puma::Configuration.new do |c|
+      c.load "test/config/custom_logger.rb"
+    end
+
+    conf.load
+    out, _ = capture_subprocess_io do
+      conf.options[:logger].write('test')
+    end
+
+    assert_match /Custom logging: test/, out
+  end
+
   def test_ssl_bind
     skip_if :jruby
     skip_unless :ssl
@@ -122,9 +135,6 @@ def test_ssl_bind_jruby
     assert_equal [ssl_binding], conf.options[:binds]
   end
 
-
-
-
   def test_ssl_bind_no_tlsv1_1
     skip_if :jruby
     skip_unless :ssl