Add Logger option to disable message broadcasts

When setting the Rails logger to log to STDOUT, it would broadcast the
log twice in development. This adds a setting that will prevent messages
from being broadcast to multiple logs, while still allowing calls to
`#close`, `#level=`, `#progname=`, and `#formatter=` to be broadcasted.

Fixes #14769, #11415

2 files changed, 8 insertions, 5 deletions

diff --git a/activesupport/lib/active_support/logger.rb b/activesupport/lib/active_support/logger.rb
index 33fccdcf95..82117a64d2 100644
--- a/activesupport/lib/active_support/logger.rb
+++ b/activesupport/lib/active_support/logger.rb
@@ -1,4 +1,3 @@
-require 'active_support/core_ext/module/attribute_accessors'
 require 'active_support/logger_silence'
 require 'logger'
 
@@ -6,16 +5,18 @@ module ActiveSupport
   class Logger < ::Logger
     include LoggerSilence
 
+    attr_accessor :broadcast_messages
+
     # Broadcasts logs to multiple loggers.
     def self.broadcast(logger) # :nodoc:
       Module.new do
         define_method(:add) do |*args, &block|
-          logger.add(*args, &block)
+          logger.add(*args, &block) if broadcast_messages
           super(*args, &block)
         end
 
         define_method(:<<) do |x|
-          logger << x
+          logger << x if broadcast_messages
           super(x)
         end
 
@@ -44,6 +45,7 @@ module ActiveSupport
     def initialize(*args)
       super
       @formatter = SimpleFormatter.new
+      @broadcast_messages = true
     end
 
     # Simple formatter which only displays the message.
diff --git a/activesupport/lib/active_support/logger_silence.rb b/activesupport/lib/active_support/logger_silence.rb
index a8efdef944..7d92256f24 100644
--- a/activesupport/lib/active_support/logger_silence.rb
+++ b/activesupport/lib/active_support/logger_silence.rb
@@ -1,8 +1,9 @@
 require 'active_support/concern'
+require 'active_support/core_ext/module/attribute_accessors'
 
 module LoggerSilence
   extend ActiveSupport::Concern
-  
+
   included do
     cattr_accessor :silencer
     self.silencer = true
@@ -21,4 +22,4 @@ module LoggerSilence
       yield self
     end
   end
-end
\ No newline at end of file
+end