Merge pull request #2663 from fluent/logrotate-windows

Support logrotate on Windows correctly. Fix #2446

lib/fluent/command/fluentd.rb

@@ -311,6 +311,16 @@
 
 require 'fluent/supervisor'
 if opts[:supervise]
+  if Fluent.windows?
+    if opts[:log_path] && opts[:log_path] != "-"
+      if opts[:log_rotate_age] || opts[:log_rotate_size]
+        require 'pathname'
+
+        log_path = Pathname(opts[:log_path]).sub_ext("-supervisor#{Pathname(opts[:log_path]).extname}").to_s
+        opts[:log_path] = log_path
+      end
+    end
+  end
   Fluent::Supervisor.new(opts).run_supervisor
 else
   if opts[:standalone_worker] && opts[:workers] && opts[:workers] > 1

lib/fluent/supervisor.rb

@@ -353,13 +353,21 @@ def initialize(path, level, chuser, chgroup, opts, log_rotate_age: nil, log_rota
         @log_rotate_size = log_rotate_size
       end
 
+      def worker_id_suffixed_path(worker_id, path)
+        require 'pathname'
+
+        Pathname(path).sub_ext("-#{worker_id}#{Pathname(path).extname}").to_s
+      end
+
       def init(process_type, worker_id)
         @opts[:process_type] = process_type
         @opts[:worker_id] = worker_id
 
         if @path && @path != "-"
           @logdev = if @log_rotate_age || @log_rotate_size
-                     Fluent::LogDeviceIO.new(@path, shift_age: @log_rotate_age, shift_size: @log_rotate_size)
+                     Fluent::LogDeviceIO.new(Fluent.windows? ?
+                                               worker_id_suffixed_path(worker_id, @path) : @path,
+                                             shift_age: @log_rotate_age, shift_size: @log_rotate_size)
                    else
                      File.open(@path, "a")
                    end