Add reraise_exception_classes keyword argument to Logger and LogDevice

lib/logger.rb

@@ -574,10 +574,14 @@ def fatal!; self.level = FATAL; end
   # - +shift_period_suffix+: sets the format for the filename suffix
   #   for periodic log file rotation; default is <tt>'%Y%m%d'</tt>.
   #   See {Periodic Rotation}[rdoc-ref:Logger@Periodic+Rotation].
+  # - +reraise_write_errors+: An array of exception classes, which will
+  #   be reraised if there is an error when writing to the log device.
+  #   The default is to swallow all exceptions raised.
   #
   def initialize(logdev, shift_age = 0, shift_size = 1048576, level: DEBUG,
                  progname: nil, formatter: nil, datetime_format: nil,
-                 binmode: false, shift_period_suffix: '%Y%m%d')
+                 binmode: false, shift_period_suffix: '%Y%m%d',
+                 reraise_write_errors: [])
     self.level = level
     self.progname = progname
     @default_formatter = Formatter.new
@@ -589,7 +593,8 @@ def initialize(logdev, shift_age = 0, shift_size = 1048576, level: DEBUG,
       @logdev = LogDevice.new(logdev, shift_age: shift_age,
         shift_size: shift_size,
         shift_period_suffix: shift_period_suffix,
-        binmode: binmode)
+        binmode: binmode,
+        reraise_write_errors: reraise_write_errors)
     end
   end
 

lib/logger/log_device.rb

@@ -11,9 +11,10 @@ class LogDevice
     attr_reader :filename
     include MonitorMixin
 
-    def initialize(log = nil, shift_age: nil, shift_size: nil, shift_period_suffix: nil, binmode: false)
+    def initialize(log = nil, shift_age: nil, shift_size: nil, shift_period_suffix: nil, binmode: false, reraise_write_errors: [])
       @dev = @filename = @shift_age = @shift_size = @shift_period_suffix = nil
       @binmode = binmode
+      @reraise_write_errors = reraise_write_errors
       mon_initialize
       set_dev(log)
       if @filename
@@ -34,16 +35,22 @@ def write(message)
           if @shift_age and @dev.respond_to?(:stat)
             begin
               check_shift_log
+            rescue *@reraise_write_errors
+              raise
             rescue
               warn("log shifting failed. #{$!}")
             end
           end
           begin
             @dev.write(message)
+          rescue *@reraise_write_errors
+            raise
           rescue
             warn("log writing failed. #{$!}")
           end
         end
+      rescue *@reraise_write_errors
+        raise
       rescue Exception => ignored
         warn("log writing failed. #{ignored}")
       end

test/logger/test_logger.rb

@@ -113,6 +113,15 @@ def test_string_level
     assert_raise(ArgumentError) { @logger.level = 'something_wrong' }
   end
 
+  def test_reraise_write_errors
+    c = Object.new
+    e = Class.new(StandardError)
+    c.define_singleton_method(:write){|*| raise e}
+    c.define_singleton_method(:close){}
+    logger = Logger.new(c, :reraise_write_errors=>[e])
+    assert_raise(e) { logger.warn('foo') }
+  end
+
   def test_progname
     assert_nil(@logger.progname)
     @logger.progname = "name"