improve delayed jobs logging

Enable auto_flush on the rails logging, so that the log is flushed to
disk after each log line, rather than each 1000 log lines.

Also redirect stdout and stderr if we've daemonized.

Change-Id: Iea89db81b4ac29a63614eff37da9216d6346a6f2
Reviewed-on: https://gerrit.instructure.com/2895
Tested-by: Hudson <[email protected]>
Reviewed-by: Bracken Mosbacker <[email protected]>
Reviewed-by: JT Olds <[email protected]>

vendor/plugins/delayed_job/lib/delayed/pool.rb

@@ -45,6 +45,7 @@ def initialize(config_filename)
         raise ArgumentError,
           "Invalid config file #{config_filename}"
       end
+      logger.auto_flushing = true
     end
 
     def environment
@@ -57,18 +58,31 @@ def daemonize
         @files_to_reopen << file unless file.closed?
       end
       Daemons.run_proc('delayed_jobs_pool',
-                       :dir => "#{RAILS_ROOT}/tmp/pids",
+                       :dir => "#{Rails.root}/tmp/pids",
                        :dir_mode => :normal) do
-        Dir.chdir(RAILS_ROOT)
+
+        Dir.chdir(Rails.root)
+        log_path = Rails.root+"log/delayed_job.log"
+
         # Re-open file handles
         @files_to_reopen.each do |file|
           begin
-            file.reopen File.join(RAILS_ROOT, 'log', 'delayed_job.log'), 'a+'
+            file.reopen(log_path, 'a+')
             file.sync = true
           rescue ::Exception
           end
         end
 
+        if $0 == 'delayed_jobs_pool'
+          # TODO: Daemons library doesn't provide a great way to redirect
+          # stdout/stderr to an arbitrary log file, and it also doesn't provid
+          # a great way to detect if we actually daemonized (or if we're
+          # running in the FG).
+          STDOUT.reopen(log_path, 'a+')
+          STDERR.reopen(STDOUT)
+          STDOUT.sync = STDERR.sync = true
+        end
+
         ActiveRecord::Base.connection_handler.clear_all_connections!
 
         start