Windows Service using win32-service and win32/daemon

Windows Services series Update 2008-6-13

Rubyforge has got some good documentation on creating a daemon so I will start with that. The first thing to do is to get the demo code which doesn't come in the gem install of win32-services but can be got by downloading the zipped code.

Run through the demo (on a local drive not a networked share as the networked shares are not visible to services) and see how you go. I extracted a small version and installed with the manual service installer to make sure I could build a service.

Here is a sample daemon code taken from the demo plus I added a timestamp and a comment on close:

LOG_FILE = 'C:\\test.log'

begin
require 'win32/daemon'

include Win32

class DemoDaemon < Daemon

def service_main
while running?
sleep 3
File.open("c:\\test.log", "a"){ |f| f.puts "Service is running #{Time.now}" }
end
end

def service_stop
File.open("c:\\test.log", "a"){ |f| f.puts "***Service stopped #{Time.now}" }
exit!
end
end

DemoDaemon.mainloop
rescue Exception => err
File.open(LOG_FILE,'a+'){ |f| f.puts " ***Daemon failure #{Time.now} err=#{err} " }
raise
end

So I copied the code to NetBeans and tried to run. I had installed win32-services (gem install win32-services), I was using Ruby 1.86 and not Jruby as the interpreter.

Make sure it has include Win32 (which is not in some early versions of the demo code) I get

daemon1.rb:28: undefined method 'mainloop' for #

With I get this due to trying to run the Daemon from the command line:

daemon1.rb:29:in `mainloop': Service_Main thread exited abnormally (Win32::Daemon::Error)

However if you create a service and then run it it will work see the following with sc.

C:\>sc create test1 binPath= "C:\ruby\bin\rubyw.exe -C c:\temp\testDaemon\lib\ main.rb" type= own start= auto
[SC] CreateService SUCCESS

C:\>sc start test1

SERVICE_NAME: test1
TYPE : 10 WIN32_OWN_PROCESS
STATE : 4 RUNNING
(STOPPABLE,PAUSABLE,ACCEPTS_SHUTDOWN)
WIN32_EXIT_CODE : 0 (0x0)
SERVICE_EXIT_CODE : 0 (0x0)
CHECKPOINT : 0x0
WAIT_HINT : 0x0
PID : 5972
FLAGS :
C:\>sc stop test1

SERVICE_NAME: test1
TYPE : 10 WIN32_OWN_PROCESS
STATE : 3 STOP_PENDING
(STOPPABLE,PAUSABLE,ACCEPTS_SHUTDOWN)
WIN32_EXIT_CODE : 0 (0x0)
SERVICE_EXIT_CODE : 0 (0x0)
CHECKPOINT : 0x0
WAIT_HINT : 0x0

C:\>

And looking at c:\Test.log you can see the results.