This is what I mean: karaf@root()> bundle:info 44
Apache Karaf :: Shell :: Core (44) ... karaf@root()> bundle:requirements 44 | grep blueprint osgi.wiring.package; (&(osgi.wiring.package=org.apache.aries.blueprint)(version>=1.5.0)(!(version>=2.0.0))) resolved by: osgi.wiring.package; org.apache.aries.blueprint 1.5.0 from org.apache.aries.blueprint.core [13] osgi.wiring.package; (&(osgi.wiring.package=org.apache.aries.blueprint.mutable)(version>=1.2.0)(!(version>=2.0.0))) resolved by: osgi.wiring.package; org.apache.aries.blueprint.mutable 1.2.0 from org.apache.aries.blueprint.core [13] osgi.wiring.package; (&(osgi.wiring.package=org.osgi.service.blueprint)(version>=1.0.0)(!(version>=2.0.0))) resolved by: osgi.wiring.package; org.osgi.service.blueprint 1.0.0 from org.apache.aries.blueprint.core [13] osgi.wiring.package; (&(osgi.wiring.package=org.osgi.service.blueprint.container)(version>=1.0.0)(!(version>=2.0.0))) resolved by: osgi.wiring.package; org.osgi.service.blueprint.container 1.0.1 from org.apache.aries.blueprint.api [11] osgi.wiring.package; (&(osgi.wiring.package=org.osgi.service.blueprint.reflect)(version>=1.0.0)(!(version>=2.0.0))) resolved by: osgi.wiring.package; org.osgi.service.blueprint.reflect 1.0.1 from org.apache.aries.blueprint.api [11] On Fri, Mar 18, 2016 at 7:20 PM, Jean-Baptiste Onofré <[email protected]> wrote: > Hi Milen, > > Karaf Shell Core (if you mean this bundle) doesn't depend on blueprint > (blueprint is not defined as a <dependency/> and so not in the manifest, > even for the command extender). > > Regards > JB > > > On 03/18/2016 07:14 PM, Milen Dyankov wrote: > >> I personally think DS is pretty much what OSGi Alliance is going to >> promote >> (together with the enRoute project) and from that perspective if any >> component framework's user base is going to grow that would be DS. But if >> you guys want to still do it the "hard way" that's fine too. It just means >> less people will be able to contribute. >> >> As for things that can not be done with DS, I don't think Christian meant >> to say everything must be rewritten! If something needs to be done >> differently (activators/tackers/...) than it can/should be. It's not all >> or >> nothing scenario IMHO. >> >> Finally about Blueprint. I keep reading in posts that Karaf got rid of >> Blueprint. Meanwhile in 4.0.4 the "Apache Karaf :: Shell :: Core" still >> depends on Blueprint. So when you say "the bundles in Karaf are >> independent" >> what exactly do you mean? >> >> Best, >> Milen >> >> >> >> On Fri, Mar 18, 2016 at 1:38 PM, Guillaume Nodet <[email protected]> >> wrote: >> >> I agree with Achim and Lukasz. >>> >>> Here are the advantages of the current solution: >>> >>> 1/ No additional dependency. One thing that I really care about is that >>> the bundles in Karaf are independent. I.e. they do not rely on an >>> extender. The benefit is that you can upgrade the bundles independently >>> and you don't have an additional bundle which cause all the bundles to be >>> refreshed / restarted. >>> >>> 2/ Very lightweight. The current framework only consist in 3 classes : >>> BaseActivator, SingleServiceTracker, >>> SingleServiceTracker$SingleServiceListener. >>> Even the annotations are not included at runtime. >>> >>> 3/ Very fast. No xml parsing, no reflection. Just the >>> OSGI-INF/karaf-tracker/ property file which is loaded by the activator. >>> So >>> it's really fast at startup. >>> >>> 4/ Very robust. Quite the contrary to what you say, I think this very >>> small >>> framework is way more robust than blueprint or DS. I spent quite some >>> time >>> load-testing karaf 4 before the release, using the bundle:load-test >>> command. >>> >>> 5/ DS exclusively uses the OSGi registry for wiring. There's no notion >>> of >>> "internal" wiring, everything is exposed. So by default, the >>> capabilities >>> / requirements contain much more than what is needed, with the additional >>> semantical change where the bundle could be wired to components coming >>> from >>> different bundles (check the bundle manifest in your branch). >>> >>> So yes, the main drawback are : limited scope and not documented, but >>> given >>> is has never been written to be used outside karaf, I don't see those as >>> real problems. If the concern is users, I'm all for advertising the use >>> of DS or Blueprint for our users, I don't think they should use our >>> internal framework which is much more low level. >>> >>> >>> 2016-03-17 16:43 GMT+01:00 Christian Schneider <[email protected] >>> >: >>> >>> We currently use some custom Activator base classes to wire the karaf >>>> bundles. The goal of this was to avoid depending on blueprint >>>> as it is a quite heavy dependency and makes it harder to use a different >>>> blueprint impl or version. >>>> >>>> There are some problems with this approach though: >>>> - It makes it harder for new people to understand what we are doing >>>> - The custom code is more error prone than a proven framework >>>> >>>> So I propose to switch our own bundles to use DS to expose and wire >>>> services. >>>> >>>> There are some advantages: >>>> - The DS annotation approach is easier to understand and more self >>>> documenting than the custom code >>>> - We get rid of the classes in util for the custom code >>>> - The scr commands help diagnose problems >>>> >>>> The main cost is that we need to always install the felix scr bundle. >>>> >>>> To prove that it can work I switched bundle core in a branch >>>> https://github.com/apache/karaf/tree/EXPERIMENTAL_DS . >>>> The DS based code works quite nicely. >>>> >>>> Btw. I found a small problem with our shell command extender. It only >>>> seems to work on all commands or none. If there is any required service >>>> missing then none of the commands is installed. >>>> This made it hard for me to diagnose problems as I was missing all >>>> bundle >>>> commands ;-) >>>> So while working on the switch I thought about two improvements to the >>>> extender: >>>> 1. Work on each command individually. So each command can activate as >>>> >>> soon >>> >>>> as the deps are met >>>> 2. Provide a service and commands to diagnose problems like the scr >>>> commands >>>> >>>> Christian >>>> >>>> -- >>>> Christian Schneider >>>> http://www.liquid-reality.de >>>> >>>> Open Source Architect >>>> http://www.talend.com >>>> >>>> >>>> >>> >>> -- >>> ------------------------ >>> Guillaume Nodet >>> ------------------------ >>> Red Hat, Open Source Integration >>> >>> Email: [email protected] >>> Web: http://fusesource.com >>> Blog: http://gnodet.blogspot.com/ >>> >>> >> >> >> > -- > Jean-Baptiste Onofré > [email protected] > http://blog.nanthrax.net > Talend - http://www.talend.com > -- http://about.me/milen
