# \[ANN\] BackgrounDRb 0.2.0 Release. Complete Rewrite

**URL:** <https://www.ruby-forum.com/t/ann-backgroundrb-0-2-0-release-complete-rewrite/74461>\
**Category:** Rails\
**Created:** [November 7, 2006, 10:44am UTC](https://www.ruby-forum.com/t/ann-backgroundrb-0-2-0-release-complete-rewrite/74461 "2006-11-07T10:44:37Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![ezmobius\_mob](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/e/958977/32.png) [@ezmobius\_mob](https://www.ruby-forum.com/u/ezmobius_mob)\
**Post date:** [November 7, 2006, 10:44am UTC](https://www.ruby-forum.com/t/ann-backgroundrb-0-2-0-release-complete-rewrite/74461/1 "2006-11-07T10:44:37Z")

</div>

Hello Folks-

```
I am really happy to announce the release of BackgrounDRb 0.2.0 .

```

This is a complete rewrite and re-architecture of this codebase. I want  
to  
thank skaar for all of his hard work. I put out a call for help with the  
new  
architecture and skaar stepped up bigtime. I had already written the  
new  
scheduler and cron compatible syntax and moved to multi process  
architecture. But he took what I had that wasn’t very whole and did a  
whopping 100 svn commits to the project! Big ups to skaar for this  
release!

= BackgrounDRb 0.2.0

!! Note that this is in an entirely different svn repo then the old  
plugin.  
Make sure you remove the old before you install the new.

[http://svn.devjavu.com/backgroundrb/tags/release-0.2.0/README](http://svn.devjavu.com/backgroundrb/tags/release-0.2.0/README)  
[http://svn.devjavu.com/backgroundrb/tags/release-0.2.0](http://svn.devjavu.com/backgroundrb/tags/release-0.2.0) (latest release)  
[http://svn.devjavu.com/backgroundrb/trunk](http://svn.devjavu.com/backgroundrb/trunk) (svn trunk)  
[http://backgroundrb.devjavu.com](http://backgroundrb.devjavu.com) (trac)  
[http://backgroundrb.rubyforge.org](http://backgroundrb.rubyforge.org) (rdoc)

Copyright (c) 2006 Ezra Z. and skaar[at]waste[dot]org

== DISCLAIMER

The 0.2.0 release of BackgrounDRb is a complete re-write of previous  
releases and is to be considered experimental, in-complete and in many  
respect untested. Our goal is to reach a release recommended for  
production use by 0.3.x. This said, this release is a more robust  
solution that the previous release.

Also note that support for Windows is deprecated with this release of  
BackgrounDRb, sorry : ( . It may work under cygwin but we have not tried  
it.

== Introduction

BackgrounDRb is a ruby job server and scheduler. It main intent is to be  
used with Ruby on Rails applications for offloading long running tasks.  
Since a rails application blocks while servicing a request it is best  
to move long running tasks off into a background process that is  
divorced  
from the http request/response cycle.

This new release of BackgrounDRb is also modular and can be used without  
Rails. So any ruby program or framework can use it.

== Technology Overview

This 0.2.x branch of BackgrounDRb introduces a completely new  
architecture  
then the previous versions. Instead of a single process, multi  
threaded environment,  
the new system uses multi process with IPC to manage workers. So each of  
your  
workers will run in their own ruby interpreter. The interface that you  
use within rails remains mostly unchanged.

The new architecture allows for a much more robust system. Each of your  
worker classes get run in their own ruby interpreter. The main server  
process  
holds a collection of references to your running worker objects. This  
acts as  
the interface or MiddleMan that you use to interact with your remote  
jobs from  
rails or other ruby client code. When workers are spawned an  
interprocess  
communication channel is opened between the MiddleMan and the worker.  
There is a heartbeat setup between parent and child processes so that if  
you kill the parent, all children processes are killed off the next  
time they try to  
hearbeat. All of this happens transparently to you as a user.

The new release comes with a brand new job scheduler. You can use  
simple triggers like repeat\_every or you can get more complex and use  
full cron compatible syntax.

Workers can be scheduled by two built in ‘trigger’ types. A simple  
‘trigger’ is specified with start, stop and interval:

require ‘active\_support’  
MiddleMan.schedule\_worker(  
:class =\> :example\_worker,  
:job\_key =\> :schedule\_test,  
:worker\_method =\> :other\_method,  
:trigger\_args =\> {  
:start =\> Time.now + 5.seconds,  
:end =\> Time.now + 10.minutes,  
:repeat\_interval =\> 30.seconds  
}

The cron trigger uses a similar syntax to cron found on UNIX systems:

MiddleMan.schedule\_worker(  
:class =\> simple\_class,  
:job\_key =\> :schedule\_test,  
:worker\_method =\> :arg\_method,  
:worker\_method\_args =\> “my argument to arg\_method”,  
:trigger\_args =\> “0 15 10 \* \* \* \*”  
)

Also note that when the server starts up, you will see 3 processes  
running.  
One of the is the MiddleMan server, one is the results worker and one is  
the logger worker. When you do a logger.info(“foo log!”) in your  
workers,  
you are actually logging to the Logger worker.

As you might imagine, this new way of managing multiple processes will  
scale a lot better then the multi threaded single process version 😉 But  
also be aware that there is still a thread pool in the middleman that  
you  
can control the size of. All this does is keep the plugin from spawning  
too  
many processes. It will allow however many workers you specify to run at  
once and any more then that will just queue up and wit for their turn to  
spawn.

If you are already a user of the old BackgrounDRb please give the new  
version a tryout. It should not require very much work to port your  
worker  
classes to the new architecture.

This is alpha software folks. It works for me™ but we will not be held  
responsible  
if it ruins your day 😉

– Ezra Z.-- Lead Rails Evangelist  
– removed\_email\_address@domain.invalid  
– Engine Y., Serious Rails Hosting  
– (866) 518-YARD (9273)

---

<div class="post-metadata">

**Author:** ![ezmobius\_mob](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/e/958977/32.png) [@ezmobius\_mob](https://www.ruby-forum.com/u/ezmobius_mob)\
**Post date:** [November 7, 2006, 10:54am UTC](https://www.ruby-forum.com/t/ann-backgroundrb-0-2-0-release-complete-rewrite/74461/2 "2006-11-07T10:54:51Z")

</div>

> This is alpha software folks. It works for me™ but we will not be held  
> responsible  
> if it ruins your day 😉

I use your Scheduler/Trigger but its fired only once:

the worker is started like this:  
def start\_worker  
MiddleMan.schedule\_worker(  
:class =\> :firewall\_worker,  
:job\_key =\> :worker,  
:trigger\_args =\> {  
:start\_time =\> Time.now + 10.seconds,  
:repeat\_interval =\> 10.seconds,  
:trigger\_type =\> :trigger  
})  
render :nothing =\> true  
end

and its defined like this:

class FirewallWorker \< BackgrounDRb::Worker::RailsBase

def do\_work(args)  
logger.info(“hello outside world”)  
end

end

As I understand the README this should be enough to trigger the worker  
periodically.

I’m at Revision 123

---

<div class="post-metadata">

**Author:** ![ezmobius\_mob](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/e/958977/32.png) [@ezmobius\_mob](https://www.ruby-forum.com/u/ezmobius_mob)\
**Post date:** [November 7, 2006, 10:59am UTC](https://www.ruby-forum.com/t/ann-backgroundrb-0-2-0-release-complete-rewrite/74461/3 "2006-11-07T10:59:16Z")

</div>

Define badly. Anyways, please grab a new copy from trunk instead of  
the release tag. There has been more work done on the scheduler and  
we are close to another release to remedy the issues.

-Ezra  
On Nov 3, 2006, at 2:24 AM, lanzm wrote:

> > > > responsible  
> > > > :start\_time =\> Time.now + 10.seconds,  
> > > > def do\_work(args)  
> > > > – Lead Rails Evangelist  
> > > > – removed\_email\_address@domain.invalid  
> > > > – Engine Y., Serious Rails Hosting  
> > > > – (866) 518-YARD (9273)
> 
> >

– Ezra Z.  
– Lead Rails Evangelist  
– removed\_email\_address@domain.invalid  
– Engine Y., Serious Rails Hosting  
– (866) 518-YARD (9273)

---

<div class="post-metadata">

**Author:** ![ezmobius\_mob](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/e/958977/32.png) [@ezmobius\_mob](https://www.ruby-forum.com/u/ezmobius_mob)\
**Post date:** [November 7, 2006, 10:57am UTC](https://www.ruby-forum.com/t/ann-backgroundrb-0-2-0-release-complete-rewrite/74461/4 "2006-11-07T10:57:46Z")

</div>

> if it ruins your day 😉  
> it did…

it works if :worker\_method and :worker\_method\_args are defined  
schedule\_worker seems to handle the default :do\_work badly.

---

<div class="post-metadata">

**Author:** ![ezmobius\_mob](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/e/958977/32.png) [@ezmobius\_mob](https://www.ruby-forum.com/u/ezmobius_mob)\
**Post date:** [November 7, 2006, 10:55am UTC](https://www.ruby-forum.com/t/ann-backgroundrb-0-2-0-release-complete-rewrite/74461/5 "2006-11-07T10:55:47Z")

</div>

The scheduler is currently broken. We will be pushing a 0.2.1 release  
tonight or tomorrow that fixes it.

-Ezra

On Nov 2, 2006, at 6:33 AM, lanzm wrote:

> def start\_worker
> 
> As I understand the README this should be enough to trigger the worker  
> periodically.
> 
> I’m at Revision 123
> 
> >

– Ezra Z.  
– Lead Rails Evangelist  
– removed\_email\_address@domain.invalid  
– Engine Y., Serious Rails Hosting  
– (866) 518-YARD (9273)