Re: IRC sessions on ServiceMix 4.0 design (was Re: ServiceMix 4.0)
Ok, sounds like we have enough people. So we just need to find a data and an hour. What about Friday 3 pm GMT, 11 am EST, 8 am PST Adrian, I'm not sure how to find a time that would suits you... Other propositions are welcome... Cheers, Guillaume Nodet On Aug 24, 2007, at 11:04 AM, Nodet Guillaume wrote: Any other people interested ? Cheers, Guillaume Nodet On Aug 23, 2007, at 3:37 PM, Kit Plummer wrote: I'd be up for a few chat sessions! On 8/23/07, Nodet Guillaume [EMAIL PROTECTED] wrote: Btw, if there is sufficient interest, we could organize irc meetings to discuss these topics and post the log to the dev list for archiving and later discussion. Cheers, Guillaume Nodet On Aug 22, 2007, at 4:59 PM, Nodet Guillaume wrote: As I explained in the other thread, I've been working on a new API for ServiceMix 4.0. Hopefully this will serve as an input for JBI 2.0. This API is available at https://svn.apache.org/repos/asf/ incubator/servicemix/branches/servicemix-4.0/api So here a few key changes: * clean integration with OSGi * the NormalizedMessage can contain not only XML * no more components * no more JBI packaging (just use OSGi bundles) * move the Channel to the Endpoint * use push delivery instead of pulling exchanges * introduce a single interface for identifying the Target of an Exchange As we remove components, everything goes down to the endpoint which become a key feature. The endpoint must implement the Endpoint interface. In OSGi, the NMR would listen to endpoints registered in the OSGi registry and call the registry to register / unregister the endpoints. As part of the endpoint registration, the NMR would inject a Channel into them, thus actually activating the endpoint. I guess I could write a sequence diagram for that (anybody knows a good tool for uml ?). In a non OSGI environment, the Endpoint will be registered in the Registry by calling the register method somehow. The Endpoint receives Exchange to be processed on the process method. I think we should keep the JBI 1.0 semantics and the endpoint use the same process as for JBI 1.0, which is send the exchange back using the Channel (with the response / fault / error / done). This will put the threading, transactions and security burden on the container itself. Which means it is easier to write JBI apps :-) Exchanges can be created using the Channel#createExchange method. The only change I'd like to integrate in the messaging API is to allow for non xml payloads and maybe untyped attachments. The body could be converted automatically to a given type if supported (I think Camel does it nicely, so I'm thinking of shamelessly copying the converter layer). I have added a few helper methods on the exchanges and messages (copy, copyFrom, ensureReReadable, display) to ease message management. For the deployment part, there is no packaging anymore. One would deploy an OSGi bundle that would register the needed endpoints in the OSGi registry. For certain types of endpoints, we may need an external activation process (such as creating a server socket for listening to HTTP requests) that may need to be shared across endpoints of a given type. In such a case, you would deploy a component that listens to new endpoints implementing HttpEndpoint for example. When a new endpoint is registered, the listener would activate a server socket that could be shared across all http endpoints. In a different way, if we have a BPEL engine, the bpel component would listen for new bundles and look for a specific file containing deployment information. The component would register new endpoints in the OSGi registry as needed (we could do that for jaxws pojos using cxf for example). So I said there is no more components, because this feature is not in the api anymore, but we will certainly need these components for some use cases. For simple endpoints, you would not need any component at all. Another benefit is that you can easily deploy a whole application inside a single OSGi bundle. Using spring-osgi, the bundle would just consist in a spring configuration file containing the endpoints declaration and expose them as OSGi services. Of course, we need to write a JBI 1.0 compatibility layer, and we could have an intermediate layer where SAs and JBI components could be OSGi bundles directly, thus leveraging the OSGi classloading mechanism. The thing I'm not completely sure about if the Target interface which aims to identify the target of an exchange. I'm thinking that some metadata are associated with endpoints (like service name, interface name, wsdl location, etc..). These metadatas could be used to retrieve targets using the Registry. We could plug in different mechanisms to query the metadata (simple lookup per id, policy based, etc...). And the result itself could be not only a single Endpoint, but could include some policies like: load balance between all the endpoint implementing the given interface,
Re: IRC sessions on ServiceMix 4.0 design (was Re: ServiceMix 4.0)
works for me. -brian On 8/25/07, Nodet Guillaume [EMAIL PROTECTED] wrote: Ok, sounds like we have enough people. So we just need to find a data and an hour. What about Friday 3 pm GMT, 11 am EST, 8 am PST Adrian, I'm not sure how to find a time that would suits you... Other propositions are welcome... Cheers, Guillaume Nodet On Aug 24, 2007, at 11:04 AM, Nodet Guillaume wrote: Any other people interested ? Cheers, Guillaume Nodet On Aug 23, 2007, at 3:37 PM, Kit Plummer wrote: I'd be up for a few chat sessions! On 8/23/07, Nodet Guillaume [EMAIL PROTECTED] wrote: Btw, if there is sufficient interest, we could organize irc meetings to discuss these topics and post the log to the dev list for archiving and later discussion. Cheers, Guillaume Nodet On Aug 22, 2007, at 4:59 PM, Nodet Guillaume wrote: As I explained in the other thread, I've been working on a new API for ServiceMix 4.0. Hopefully this will serve as an input for JBI 2.0. This API is available at https://svn.apache.org/repos/asf/ incubator/servicemix/branches/servicemix-4.0/api So here a few key changes: * clean integration with OSGi * the NormalizedMessage can contain not only XML * no more components * no more JBI packaging (just use OSGi bundles) * move the Channel to the Endpoint * use push delivery instead of pulling exchanges * introduce a single interface for identifying the Target of an Exchange As we remove components, everything goes down to the endpoint which become a key feature. The endpoint must implement the Endpoint interface. In OSGi, the NMR would listen to endpoints registered in the OSGi registry and call the registry to register / unregister the endpoints. As part of the endpoint registration, the NMR would inject a Channel into them, thus actually activating the endpoint. I guess I could write a sequence diagram for that (anybody knows a good tool for uml ?). In a non OSGI environment, the Endpoint will be registered in the Registry by calling the register method somehow. The Endpoint receives Exchange to be processed on the process method. I think we should keep the JBI 1.0 semantics and the endpoint use the same process as for JBI 1.0, which is send the exchange back using the Channel (with the response / fault / error / done). This will put the threading, transactions and security burden on the container itself. Which means it is easier to write JBI apps :-) Exchanges can be created using the Channel#createExchange method. The only change I'd like to integrate in the messaging API is to allow for non xml payloads and maybe untyped attachments. The body could be converted automatically to a given type if supported (I think Camel does it nicely, so I'm thinking of shamelessly copying the converter layer). I have added a few helper methods on the exchanges and messages (copy, copyFrom, ensureReReadable, display) to ease message management. For the deployment part, there is no packaging anymore. One would deploy an OSGi bundle that would register the needed endpoints in the OSGi registry. For certain types of endpoints, we may need an external activation process (such as creating a server socket for listening to HTTP requests) that may need to be shared across endpoints of a given type. In such a case, you would deploy a component that listens to new endpoints implementing HttpEndpoint for example. When a new endpoint is registered, the listener would activate a server socket that could be shared across all http endpoints. In a different way, if we have a BPEL engine, the bpel component would listen for new bundles and look for a specific file containing deployment information. The component would register new endpoints in the OSGi registry as needed (we could do that for jaxws pojos using cxf for example). So I said there is no more components, because this feature is not in the api anymore, but we will certainly need these components for some use cases. For simple endpoints, you would not need any component at all. Another benefit is that you can easily deploy a whole application inside a single OSGi bundle. Using spring-osgi, the bundle would just consist in a spring configuration file containing the endpoints declaration and expose them as OSGi services. Of course, we need to write a JBI 1.0 compatibility layer, and we could have an intermediate layer where SAs and JBI components could be OSGi bundles directly, thus leveraging the OSGi classloading mechanism. The thing I'm not completely sure about if the Target interface which aims to identify the target of an exchange. I'm thinking that some metadata are associated with endpoints (like service name, interface name, wsdl location, etc..). These metadatas could be used to retrieve targets using the Registry.
Re: IRC sessions on ServiceMix 4.0 design (was Re: ServiceMix 4.0)
Me too. I think. -- Kit Plummer Nobody-in-Charge @ Black:Hole:Logic http://www.blackholelogic.com
