Allow users to provide custom formatters to Logger. [aeden] Closes #7106, #2484

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6225 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

 *SVN*
 
+* Allow users to provide custom formatters to Logger. [aeden]
+
 * Hash#to_query CGI-escapes its keys.  [Jeremy Kemper]
 
 * Deprecation: warn on stderr if RAILS_DEFAULT_LOGGER isn't set yet.  [Jeremy

activesupport/lib/active_support/clean_logger.rb

 require 'logger'
 require File.dirname(__FILE__) + '/core_ext/class/attribute_accessors'
 
-class Logger #:nodoc:
+# Extensions to the built in Ruby logger.
+#
+# If you want to use the default log formatter as defined in the Ruby core, then you 
+# will need to set the formatter for the logger as in:
+#
+#   logger.formatter = Formatter.new
+#
+# You can then specify the datetime format, for example:
+#
+#   logger.datetime_format = "%Y-%m-%d"
+class Logger
+  # Set to false to disable the silencer
   cattr_accessor :silencer
   self.silencer = true
-
+  
   # Silences the logger for the duration of the block.
   def silence(temporary_level = Logger::ERROR)
     if silencer
@@ -18,6 +29,35 @@ def silence(temporary_level = Logger::ERROR)
       yield self
     end
   end
+  
+  alias :old_datetime_format= :datetime_format=
+  # Logging date-time format (string passed to +strftime+). Ignored if the formatter
+  # does not respond to datetime_format=.
+  def datetime_format=(datetime_format)
+    formatter.datetime_format = datetime_format if formatter.respond_to?(:datetime_format=)
+  end
+  
+  alias :old_datetime_format :datetime_format
+  # Get the logging datetime format. Returns nil if the formatter does not support
+  # datetime formatting.
+  def datetime_format
+    formatter.datetime_format if formatter.respond_to?(:datetime_format)
+  end
+  
+  alias :old_formatter :formatter
+  # Get the current formatter. The default formatter is a SimpleFormatter which only
+  # displays the log message
+  def formatter
+    @formatter ||= SimpleFormatter.new
+  end
+  
+  # Simple formatter which only displays the message.
+  class SimpleFormatter < Logger::Formatter
+    # This method is invoked when a log event occurs
+    def call(severity, timestamp, progname, msg)
+      "#{msg}\n"
+    end
+  end
 
   private
     alias old_format_message format_message
@@ -28,11 +68,11 @@ def silence(temporary_level = Logger::ERROR)
     # with Logger from 1.8.3 and vice versa.
     if method_defined?(:formatter=)
       def format_message(severity, timestamp, progname, msg)
-        "#{msg}\n"
+        formatter.call(severity, timestamp, progname, msg)
       end
     else
       def format_message(severity, timestamp, msg, progname)
-        "#{msg}\n"
+        formatter.call(severity, timestamp, progname, msg)
       end
     end
 end

activesupport/test/clean_logger_test.rb

@@ -40,6 +40,13 @@ def test_silence
 
     assert_equal "error\nfatal\nerror\nfatal\nunsilenced\n", @out.string
   end
+  
+  def test_datetime_format
+    @logger.formatter = Logger::Formatter.new
+    @logger.datetime_format = "%Y-%m-%d"
+    @logger.debug 'debug'
+    assert_match(/D, \[\d\d\d\d-\d\d-\d\d#\d+\] DEBUG -- : debug/, @out.string)
+  end
 end
 
 class CleanLogger_182_to_183_Test < Test::Unit::TestCase