BufferedLogger#auto_flushing = N flushes the log every N messages. Buffers...

BufferedLogger#auto_flushing = N flushes the log every N messages. Buffers with an array instead of string.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7732 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

 *SVN*
 
+* BufferedLogger#auto_flushing = N flushes the log every N messages. Buffers with an array instead of string.  [Jeremy Kemper]
+
 * Fixed Date#xmlschema for dates outside the range of what can be created with Time #9744 [gbuesing]
 
 

activesupport/lib/active_support/buffered_logger.rb

@@ -29,13 +29,14 @@ def silence(temporary_level = ERROR)
       end
     end
 
-    attr_accessor :level, :auto_flushing
+    attr_accessor :level
+    attr_reader :auto_flushing
     attr_reader :buffer
 
     def initialize(log, level = DEBUG)
       @level         = level
-      @buffer        = ""
-      @auto_flushing = true
+      @buffer        = []
+      @auto_flushing = 1
 
       if log.respond_to?(:write)
         @log = log
@@ -56,7 +57,7 @@ def add(severity, message = nil, progname = nil, &block)
       # Ensures that the original message is not mutated.
       message = "#{message}\n" unless message[-1] == ?\n
       @buffer << message
-      flush if auto_flushing
+      auto_flush if auto_flushing
       message
     end
 
@@ -72,9 +73,25 @@ def #{severity.downcase}?
       EOT
     end
 
+    # Set the auto-flush period. Set to true to flush after every log message,
+    # to an integer to flush every N messages, or to false, nil, or zero to
+    # never auto-flush. If you turn auto-flushing off, be sure to regularly
+    # flush the log yourself -- it will eat up memory until you do.
+    def auto_flushing=(period)
+      case period
+      when true
+        @auto_flushing = 1
+      when 0
+        @auto_flushing = false
+      when false, nil, Integer
+        @auto_flushing = period
+      else
+        raise ArgumentError, "Unrecognized auto_flushing period: #{period.inspect}"
+      end
+    end
+
     def flush
-      return if @buffer.size == 0
-      @log.write(@buffer.slice!(0..-1))
+      @log.write(@buffer.slice!(0..-1)) unless @buffer.empty?
     end
 
     def close
@@ -82,5 +99,10 @@ def close
       @log.close if @log.respond_to?(:close)
       @log = nil
     end
+
+    protected
+      def auto_flush
+        flush if @buffer.size >= @auto_flushing
+      end
   end
-end
+end
\ No newline at end of file

activesupport/test/buffered_logger_test.rb

@@ -8,7 +8,7 @@ def setup
     @output  = StringIO.new
     @logger  = ActiveSupport::BufferedLogger.new(@output)
   end
-  
+
   def test_should_log_debugging_message_when_debugging
     @logger.level = Logger::DEBUG
     @logger.add(Logger::DEBUG, @message)
@@ -26,35 +26,62 @@ def test_should_add_message_passed_as_block_when_using_add
     @logger.add(Logger::INFO) {@message}
     assert @output.string.include?(@message)
   end
-  
+
   def test_should_add_message_passed_as_block_when_using_shortcut
     @logger.level = Logger::INFO
     @logger.info {@message}
     assert @output.string.include?(@message)
   end
-  
+
   def test_should_convert_message_to_string
     @logger.level = Logger::INFO
     @logger.info @integer_message
     assert @output.string.include?(@integer_message.to_s)
   end
-  
+
   def test_should_convert_message_to_string_when_passed_in_block
     @logger.level = Logger::INFO
     @logger.info {@integer_message}
     assert @output.string.include?(@integer_message.to_s)
   end
-  
+
   def test_should_not_evaluate_block_if_message_wont_be_logged
     @logger.level = Logger::INFO
     evaluated = false
     @logger.add(Logger::DEBUG) {evaluated = true}
-    assert evaluated == false  
+    assert evaluated == false
   end
-  
+
   def test_should_not_mutate_message
     message_copy = @message.dup
     @logger.info @message
     assert_equal message_copy, @message
   end
+
+
+  [false, nil, 0].each do |disable|
+    define_method "test_disabling_auto_flush_with_#{disable.inspect}_should_buffer_until_explicit_flush" do
+      @logger.auto_flushing = disable
+
+      4.times do
+        @logger.info 'wait for it..'
+        assert @output.string.empty?, @output.string
+      end
+
+      @logger.flush
+      assert !@output.string.empty?, @logger.buffer.size
+    end
+  end
+
+  def test_should_auto_flush_every_n_messages
+    @logger.auto_flushing = 5
+
+    4.times do
+      @logger.info 'wait for it..'
+      assert @output.string.empty?, @output.string
+    end
+
+    @logger.info 'there it is.'
+    assert !@output.string.empty?, @output.string
+  end
 end