Plugin-API

[Pierre Baillet]

Hi, --

On Thu, Nov 20, 2003, Christian Kruse wrote:

> Hi there,
>
> I'm writing an application in Ruby which should be easy to extend. One
> should be able to write a plugin for this application and should be able
> to load it with an entry in the config file, e.g.
>
> [snip]
> What's the "ruby way" to do this?
>
> Greetings,
> CK
>

Maybe you can have a look at the rbot source code
([url]http://www.linuxbrit.co.uk[/url]) which has a quite good system of plugin
auto discovery (and reload too)

HTH,
--
Pierre Baillet
It is a good viewpoint to see the world as a dream. When you have something
like a nightmare, you will wake up and tell yourself that it was only a dream.
It is said that the world we live in is not a bit different from this.
Ghost Dog - The Way of the Samouraï

[Christian Kruse]

Hi there,

I'm writing an application in Ruby which should be easy to extend. One
should be able to write a plugin for this application and should be able
to load it with an entry in the config file, e.g.

Load ContentFilter

Perl I would use eval statements like

eval "use $modname";
die $@ if $@;

to load the plugin. In Perl the plugin would look like the following:

push @{$main::Plugins->{state}},new Module;

package Module;

sub new() {
}
....

1;

What's the "ruby way" to do this?

Greetings,
CK

[Robert Klemme]

"Christian Kruse" <ckruse@defunced.de> schrieb im Newsbeitrag
news:8mgipb.a13.ln@news.defunced.de...

> Hi there,
>
> I'm writing an application in Ruby which should be easy to extend. One
> should be able to write a plugin for this application and should be able
> to load it with an entry in the config file, e.g.
>
> Load ContentFilter
>
> Perl I would use eval statements like
>
> eval "use $modname";
> die $@ if $@;
>
> to load the plugin. In Perl the plugin would look like the following:
>
> push @{$main::Plugins->{state}},new Module;
>
> package Module;
>
> sub new() {
> }
> ....
>
> 1;
>
> What's the "ruby way" to do this?

Assuming the config file is evaluated as ruby code you can do:

15:33:28 [temp]: for file in PluginBase.rb SomePlugin.rb config.rb
application.rb ; do echo "---- $file ----" ; cat "$file" ; done
---- PluginBase.rb ----
class PluginBase
end

---- SomePlugin.rb ----
require 'PluginBase'

class PluginClass < PluginBase
# functionality
end

$plugin_registry << PluginClass
---- config.rb ----
require 'SomePlugin'

---- application.rb ----
# other classes

$plugin_registry = []

eval File.readlines("config.rb").join

p $plugin_registry

15:33:36 [temp]:


As easy as that...

robert

[gabriele renzi]

il Thu, 20 Nov 2003 14:47:52 +0100, Christian Kruse
<ckruse@defunced.de> ha scritto::


you may find this thread useful:
[url]http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/48648[/url]

[Curt Hibbs]

On Thu, Nov 20, 2003, Christian Kruse wrote:

> Hi there,
>
> I'm writing an application in Ruby which should be easy to extend. One
> should be able to write a plugin for this application and should be able
> to load it with an entry in the config file, e.g.
>
> [snip]
> What's the "ruby way" to do this?
>
> Greetings,
> CK

You might want to look at the plugin system used by FreeRIDE which is called
FreeBASE and has been packaged as a separate download. See:

[url]http://freeride.rubyforge.org/wiki/wiki.pl?FreeBASE[/url]

The FreeRIDE IDE is completely (100%) implemented as a set of plugins, with
the exception of FreeBASE, which is the plugin manager. It has sophisticated
facilities for specifying dependencies between plugins (which affects the
load order of plugins) and includes a high-performance messaging engine (the
databus) that allows plugins to communicate with each other while minimizing
coupling.

However, if your plugin needs are very simple, this might be overkill.

Curt

[Christian Kruse]

Hoi,

> [...]

Thank you very much for your help.

Greetings,
CK