[forge-dev] OSGi prototype

Tue Oct 16 14:29:48 EDT 2012

Getting closer. I can run it but nothing shows up in the console  (eclipse)
and nothing happens when I enter commands.

On Tue, Oct 16, 2012 at 2:25 PM, Lincoln Baxter, III <
lincolnbaxter at gmail.com> wrote:

> Fixed. Still trying to figure out exactly how to get this thing to run :)
> will get there. Thanks!
>
>
> On Tue, Oct 16, 2012 at 2:13 PM, Paul Bakker <paul.bakker.nl at gmail.com>wrote:
>
>> not sure, I might have accidentally used some java 7 features... No real
>> reason for it though so should be easy to fix.
>>
>> Sent from my iPhone
>>
>> On 16 okt. 2012, at 20:05, "Lincoln Baxter, III" <lincolnbaxter at gmail.com>
>> wrote:
>>
>> Having trouble getting JDK 1.7.0 on my machine... did you use 1.7 or will
>> 1.6 suffice?
>>
>> ~Lincoln
>>
>> On Mon, Oct 15, 2012 at 3:35 PM, Paul Bakker <paul.bakker.nl at gmail.com>wrote:
>>
>>> THE zip contains a eclipse plugin site. Configure it as such in the
>>> eclipse install wizard.
>>>
>>> Sent from my iPhone
>>>
>>> On 15 okt. 2012, at 21:01, "Lincoln Baxter, III" <
>>> lincolnbaxter at gmail.com> wrote:
>>>
>>> How do you install BNDTools 2.0 once you have downloaded and extracted
>>> the archive.zip latest build from the CI server?
>>>
>>> Thanks,
>>> ~Lincoln
>>>
>>> On Sat, Oct 13, 2012 at 4:17 PM, Paul Bakker <paul.bakker.nl at gmail.com>wrote:
>>>
>>>> Hi all,
>>>>
>>>> As discussed in last Wednesday meeting I created a basic OSGi based
>>>> prototype for Forge 2.0. This is not even close to a port of Forge, but
>>>> rather a demonstration on how the basic programming model could work for
>>>> further discussion.
>>>>
>>>> The prototype contains the following:
>>>> 1) A jline shell that can execute plugins
>>>> 2) A plugin example using Felix Dependency Manager
>>>> 3) A plugin using SCR annotations
>>>> 4) A simple Facet that can be injected
>>>>
>>>> Note that jline is not configured properly, I didn't really look into
>>>> that.
>>>>
>>>> Plugins are OSGi services, so they need to be registered to the service
>>>> registry. This can be done using any dependency injection framework in
>>>> OSGi, for the example I have focussed on Felix Dependency Manager and
>>>> Declarative Services with annotations.
>>>>
>>>> A plugin doesn't need to be annotated and doesn't need to implement any
>>>> interfaces. The only requirement is a service property "plugin" that
>>>> defines the name (alias) of the plugin. Service properties are a standard
>>>> OSGi services feature.
>>>>
>>>> The Forge shell listens to plugin registrations and de-registrations.
>>>> Whenever a new plugin service is registered to the service registry it will
>>>> be picked up, and whenever a service is unregistered it will be removed
>>>> from the list of services. This is very valuable for adding/(re)installing
>>>> new plugins while running Forge. While this is kind of hacky in the current
>>>> Forge implementation, this is one of the very basic features of OSGi
>>>> services. The fact that it only requires a few lines of code sort of proves
>>>> that :-)
>>>>
>>>> Another important part of Forge are Facets and dependency injection of
>>>> Facets. Facets are also OSGi services, but in this case they should publish
>>>> an interface (that's the whole idea of Facets). In the prototype there is a
>>>> Project interface defined in the exported api package. This interface is
>>>> implemented and published as a service by the ProjectFacet project. Again
>>>> I'm using Felix Dependency Manager to register the service, but we could
>>>> use annotations as well. The Project facet is then injected into the
>>>> ExamplePlugin (using Felix DM again).
>>>>
>>>> The programming model for Plugin developers is very similar to the
>>>> current model. You define a pojo and register it to the registry using
>>>> either an annotation or an Activator. Because we package plugins as OSGi
>>>> bundles we do need a manifest. When using BndTools this is all generated
>>>> automatically, you don't even have to know it's there. When using Maven you
>>>> can use the Maven Bundle Plugin, which is also based on Bnd and does
>>>> basically the same. As a plugin developer you just add the plugin to the
>>>> POM (or Forge does that for you, I already have a plugin for that...) and
>>>> that's it. No need to worry about import/exports or anything else OSGi
>>>> related. Packaging a plugin could be done in several ways (from code,
>>>> picking up from disk etc.). Basically you just need to install the bundle
>>>> into the OSGi framework.
>>>>
>>>> As a core developer the model is very similar too. Basically you still
>>>> just develop internal plugins and facets the same way you would today. We
>>>> can be more strict about interfaces and versioning however. Public
>>>> classes/interfaces must be explicitly export in the Manifest. This is a
>>>> good thing! It's impossible to use non-exported packages in OSGi, so we can
>>>> strictly enforce that plugins only use public APIs. Exported packages are
>>>> also versioned. A client of a class/interface will usually import the
>>>> package using a version range up to the next major version for example.
>>>> Using this you can have semantic versioning, and compatibility problems
>>>> will be more predictable.
>>>>
>>>> This prototype just shows the very basic model. If we agree this is a
>>>> good model to move forward with, we should look at some more detailed
>>>> requirements such as plugin sharing/inheritance and library usage. Before
>>>> hacking away we should probably come up with some requirements for that :-)
>>>>
>>>> Running the prototype:
>>>> The code is on github: https://github.com/paulbakker/forgeosgi.
>>>> Note that you need BndTools 2.0 to play with the code. This is an
>>>> Eclipse plugin that does all the OSGi related stuff. BndTools 2.0 is not
>>>> released yet (but I'm using it daily) and you can get it from the latest
>>>> build:
>>>> https://bndtools.ci.cloudbees.com/job/bndtools.master/lastSuccessfulBuild/artifact/
>>>> .
>>>> After installing BndTools you can create a workspace and import the
>>>> projects. You can run from Eclipse by opening org.jboss.forge.shell,
>>>> right-click on forge.bndrun and select "Run as->OSGi run". This runs Forge
>>>> in an Eclipse console which is not very useful because it messes up the
>>>> shell. It does give you hot code replacement however. Packaging Forge is as
>>>> simple as opening the bndrun file, go to the run tab, and click export. You
>>>> get a executable jar file that contains everything. Hot code replacement in
>>>> a Forge instance running in a normal terminal should also be possible, but
>>>> we have to do some work for that (normally you would just use the Eclipse
>>>> console). The two plugins both support a "setup" command and can be
>>>> executed as "example setup" and "annotated setup".
>>>>
>>>> Cheers,
>>>>
>>>> Paul
>>>> _______________________________________________
>>>> forge-dev mailing list
>>>> forge-dev at lists.jboss.org
>>>> https://lists.jboss.org/mailman/listinfo/forge-dev
>>>>
>>>
>>>
>>>
>>> --
>>> Lincoln Baxter, III
>>> http://ocpsoft.org
>>> "Simpler is better."
>>>
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>>> forge-dev at lists.jboss.org
>>> https://lists.jboss.org/mailman/listinfo/forge-dev
>>>
>>>
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>>> forge-dev at lists.jboss.org
>>> https://lists.jboss.org/mailman/listinfo/forge-dev
>>>
>>>
>>
>>
>> --
>> Lincoln Baxter, III
>> http://ocpsoft.org
>> "Simpler is better."
>>
>> _______________________________________________
>> forge-dev mailing list
>> forge-dev at lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/forge-dev
>>
>>
>> _______________________________________________
>> forge-dev mailing list
>> forge-dev at lists.jboss.org
>> https://lists.jboss.org/mailman/listinfo/forge-dev
>>
>>
>
>
> --
> Lincoln Baxter, III
> http://ocpsoft.org
> "Simpler is better."
>

-- 
Lincoln Baxter, III
http://ocpsoft.org
"Simpler is better."
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