Ensure TaggegLogging is thread safe.

2 files changed, 51 insertions, 14 deletions

diff --git a/activesupport/lib/active_support/tagged_logging.rb b/activesupport/lib/active_support/tagged_logging.rb
index 0cabb528ef..aff416a9eb 100644
--- a/activesupport/lib/active_support/tagged_logging.rb
+++ b/activesupport/lib/active_support/tagged_logging.rb
@@ -13,20 +13,20 @@ module ActiveSupport
   class TaggedLogging
     def initialize(logger)
       @logger = logger
-      @tags   = []
+      @tags   = Hash.new { |h,k| h[k] = [] }
     end
 
-    def tagged(*tags)
-      new_tags = Array.wrap(tags).flatten
-      @tags += new_tags
+    def tagged(*new_tags)
+      tags     = current_tags
+      new_tags = Array.wrap(new_tags).flatten
+      tags.concat new_tags
       yield
     ensure
-      new_tags.size.times { @tags.pop }
+      new_tags.size.times { tags.pop }
     end
 
-
     def add(severity, message = nil, progname = nil, &block)
-      @logger.add(severity, "#{tags}#{message}", progname, &block)
+      @logger.add(severity, "#{tags_text}#{message}", progname, &block)
     end
 
     %w( fatal error warn info debug unkown ).each do |severity|
@@ -37,17 +37,26 @@ module ActiveSupport
       EOM
     end
 
+    def flush(*args)
+      @tags.delete(Thread.current)
+      @logger.flush(*args) if @logger.respond_to?(:flush)
+    end
 
     def method_missing(method, *args)
       @logger.send(method, *args)
     end
-    
 
-    private
-      def tags
-        if @tags.any?
-          @tags.collect { |tag| "[#{tag}]" }.join(" ") + " "
-        end
+    protected
+
+    def tags_text
+      tags = current_tags
+      if tags.any?
+        tags.collect { |tag| "[#{tag}]" }.join(" ") + " "
       end
+    end
+
+    def current_tags
+      @tags[Thread.current]
+    end
   end
 end
diff --git a/activesupport/test/tagged_logging_test.rb b/activesupport/test/tagged_logging_test.rb
index a1504c6ce4..b12b12f32c 100644
--- a/activesupport/test/tagged_logging_test.rb
+++ b/activesupport/test/tagged_logging_test.rb
@@ -3,9 +3,15 @@ require 'active_support/core_ext/logger'
 require 'active_support/tagged_logging'
 
 class TaggedLoggingTest < ActiveSupport::TestCase
+  class MyLogger < ::Logger
+    def flush(*)
+      info "[FLUSHED]"
+    end
+  end
+
   setup do
     @output = StringIO.new
-    @logger = ActiveSupport::TaggedLogging.new(Logger.new(@output))
+    @logger = ActiveSupport::TaggedLogging.new(MyLogger.new(@output))
   end
 
   test "tagged once" do
@@ -23,6 +29,28 @@ class TaggedLoggingTest < ActiveSupport::TestCase
     assert_equal "[BCX] [Jason] [New] Funky time\n", @output.string
   end
 
+  test "keeps each tag in their own thread" do
+    @logger.tagged("BCX") do
+      Thread.new do
+        @logger.tagged("OMG") { @logger.info "Cool story bro" }
+      end.join
+      @logger.info "Funky time"
+    end
+    assert_equal "[OMG] Cool story bro\n[BCX] Funky time\n", @output.string
+  end
+
+  test "cleans up the taggings on flush" do
+    @logger.tagged("BCX") do
+      Thread.new do
+        @logger.tagged("OMG") do
+          @logger.flush
+          @logger.info "Cool story bro"
+        end
+      end.join
+    end
+    assert_equal "[FLUSHED]\nCool story bro\n", @output.string
+  end
+
   test "mixed levels of tagging" do
     @logger.tagged("BCX") do
       @logger.tagged("Jason") { @logger.info "Funky time" }