On Thu, Jun 3, 2010 at 9:14 AM, ant elder <[email protected]> wrote: > On Thu, Jun 3, 2010 at 9:08 AM, Simon Laws <[email protected]> wrote: >> On Wed, Jun 2, 2010 at 9:43 PM, Luciano Resende <[email protected]> wrote: >>> My understanding is that we use the Tuscany Samples to help newcomers >>> to get familiar with SCA and help them understand the basic concepts >>> of how to build a SCA Composite Application as well as to demonstrate >>> how some specific technologies might get >>> incorporated/configured/consumed in SCA way. Based on this, can >>> someone help me answer a basic question : >>> >>> I'm new to Tuscany, and was able to load >>> "sample-contribution-implementation-java-calculator" into my >>> development IDE, but I can't figure out how to run/debug this >>> application. BTW, I'm also getting a little confused with what is a >>> contribution versus implementation... as I said... I'm just trying to >>> get started with Tuscany. Could someone please help. >>> >>> >>> -- >>> Luciano Resende >>> http://people.apache.org/~lresende >>> http://twitter.com/lresende1975 >>> http://lresende.blogspot.com/ >>> >> >> Sure >> >> In SCA: >> >> - composite applications are described through XML configuration in a >> ".composite" file. These composite files describe components. >> Components can be "implemented" using a variety of technologies. >> Components can be "wired" together, or assembled, using a variety of >> technologies. >> - the ".composite" file, and the resources it requires to run, are >> packed in what SCA calls a contribution. Basically any hierarchical >> structure, e.g. zip, jar, war etc. >> - you run the contribution. The SCA specifications don't define how to >> do this and in Tuscany we have numerous ways depending on your >> environment, for example, you can run a contribution from: >> -- the command line (tuscany.bat), >> -- from a Java program (using the Tuscany Node interface), >> -- from Maven using the Tuscany plugin, >> -- from a Web App container (by packaging the Tuscany runtime in a WAR), >> -- from a Web App container (with the Tuscany runtime integrated >> directly into the container) >> -- etc. >> >> What's important here in terms of understanding what SCA is all about >> is that you follow three steps. >> >> 1 construct a composite application >> 2 package it as a contribution >> 3 run the contribution >> >> There are of course complications, for example, an application can >> comprise multiple contributions, there are peculiarities of the >> environments from which you can run Tuscany etc. but basically they >> are variations on these three steps. >> >> Hope that helps >> > > Thats a good description. > > There is one part i think we need to do better on which is with the > "run the contribution", which should be "install the contribution to > an SCA domain" We need to make that clearer in the readme's, website, > APIs etc, and to have better samples and doc on the creation of SCA > domains. > > ...ant >
Very good point. I think we've been very weak on that and it has lead to much confusion when comparing what Tuscany provides with what people, who have read about SCA elsewhere, expect. I would say we've been 1 - good at demonstrating how to build composite files and the different SCA features on offer there 2 - poor at demonstrating clearly how to package composites and resources as contribution(s) 3 - poor at demonstrating clearly what can be done with a contribution in terms of contributing it to an SCA domain and having it run None of this discussion precludes any particular sample (I'm personally not trying to remove samples, or sample configurations, that people find useful - I did reply to Raymond's thread to that effect). I started the previous thread on tidying samples to try and address what appear (to me at least) to be failings in Tuscany for 2 and 3. Simon -- Apache Tuscany committer: tuscany.apache.org Co-author of a book about Tuscany and SCA: tuscanyinaction.com
