Always flush logger at exit

Prior to this change, running code via script/runner would demonstrate
different logging behavior than running the same code via a rake task.
In production mode the script/runner approach would always flush the
logger, but the rake-based approach would not automatically flush the
logger. This discrepancy violates the principle of least surprise, and
it could lead to the loss of important production logging data.

This change removes special-case code in the "runner" command, and
replaces it with a general solution to ensure that the logger gets
flushed at exit. This solution works for "runner", "console", "server",
rake tasks, and any other process that loads the Rails environment.

2 files changed, 9 insertions, 14 deletions

diff --git a/railties/lib/rails/application/bootstrap.rb b/railties/lib/rails/application/bootstrap.rb
index 9c9d85eed6..0c02e5758e 100644
--- a/railties/lib/rails/application/bootstrap.rb
+++ b/railties/lib/rails/application/bootstrap.rb
@@ -37,6 +37,7 @@ module Rails
           )
           logger
         end
+        at_exit { Rails.logger.flush if Rails.logger.respond_to?(:flush) }
       end
 
       # Initialize cache early in the stack so railties can make use of it.
diff --git a/railties/lib/rails/commands/runner.rb b/railties/lib/rails/commands/runner.rb
index 1a91d477ec..ddd08a32ee 100644
--- a/railties/lib/rails/commands/runner.rb
+++ b/railties/lib/rails/commands/runner.rb
@@ -39,18 +39,12 @@ ENV["RAILS_ENV"] = options[:environment]
 require APP_PATH
 Rails.application.require_environment!
 
-begin
-  if code_or_file.nil?
-    $stderr.puts "Run '#{$0} -h' for help."
-    exit 1
-  elsif File.exist?(code_or_file)
-    $0 = code_or_file
-    eval(File.read(code_or_file), nil, code_or_file)
-  else
-    eval(code_or_file)
-  end
-ensure
-  if defined? Rails
-    Rails.logger.flush if Rails.logger.respond_to?(:flush)
-  end
+if code_or_file.nil?
+  $stderr.puts "Run '#{$0} -h' for help."
+  exit 1
+elsif File.exist?(code_or_file)
+  $0 = code_or_file
+  eval(File.read(code_or_file), nil, code_or_file)
+else
+  eval(code_or_file)
 end