[ecf-dev] ECF 3.11.0: new provider api

[Scott Lewis <slewis@xxxxxxxxxxxxx>]

Hi Folks,

Over the past year, a lot of work has gone into the creation of new 
remote services distribution providers...e.g.

1) Websockets using R-OSGi [1]
2) MQTT [2]
3) Hazelcast [3]
4) JaxRS based providers (Jersey) [4]

I expect that there will be consumer desires for using other 
distribution providers, as this ability to create and use custom 
distribution providers with standards-based remoting (OSGi remote 
services) is very useful for integration.

I would like to make it easier for us and other to create new 
distribution providers, so I decided to put in place a small new API to 
make it easier for those that might wish to do so.

It's currently implemented as 3 new classes in a new package 
'org.eclipse.ecf.remoteservices.provider' [5].  The notion is is that a 
provider implementation can create an instance of 
IRemoteServiceDistributionProvider and register this instance via the 
OSGi whiteboard pattern...e.g.:

bundleContext.registerService(IRemoteServiceDistributionProvider.class, 
myProviderImpl, null);

and the myProviderImpl will be used by ECF's RSA implementation at 
export and/or import time.

I've created a RemoteServiceDistributionProvider class, so that the 
myProviderImpl can use the now-common 'builder' pattern to create 
myProviderImpl:

IRemoteServiceDistributionProvider myProviderImpl = new 
RemoteServiceDistributionProvider.Builder().setName('com.mycorp.myprovider.client').setInstantiator(new 
MyContainerInstantiator()).build();

The name 'com.mycorp.myprovider.client' and the 
MyContainerInstantiator() are required and define the relationship 
between the container/config type (e.g. 'ecf.generic.client') and the 
IContainerInstantiator that's responsible for creating IContainer 
instances associated with the container/config type. Below is a full 
example for the Hazelcast provider.   Note that using ds would also work 
great.

The Builder also allows other customization (e.g. defining a new 
Namespace), and flexibility it's currently possible for providers to 
sub-class RemoteServiceDistributionProvider .

I would like to include this new API in 3.11.0, which I propose 
releasing sometime in September.  Since it's new API a minor release is 
called for and requires a review.

If you have any comments, suggestions, or criticisms of this new API 
let's discuss here on this list.

Thanks,

Scott

[1] https://github.com/ECF/Websockets
[2] https://github.com/ECF/Mqtt-Provider
[3] https://github.com/ECF/HazelcastProvider
[4] https://github.com/ECF/JaxRSProviders
[5] 
http://git.eclipse.org/c/ecf/org.eclipse.ecf.git/tree/framework/bundles/org.eclipse.ecf.remoteservice/src/org/eclipse/ecf/remoteservice/provider


        // Build and register hazelcast manager distribution provider
context.registerService(IRemoteServiceDistributionProvider.class,
                new RemoteServiceDistributionProvider.Builder()
.setName(HazelcastManagerContainer.HAZELCAST_MANAGER_NAME)
                        .setInstantiator(new 
HazelcastManagerContainer.Instantiator())
                        .setDescription("ECF Hazelcast 
Manager").setServer(true)
                        .setAdapterConfig(new AdapterConfig(new 
RemoteServiceContainerAdapterFactory(),
                                HazelcastManagerContainer.class))
                        .build(),
                null);