CVS update of web/xml/root/fscript (index.xml)

["Pierre-Charles David" <pcdavid@xxxxxxxxxxxxxxxxxxxxxxxxx>]

    Date: Tuesday, February 20, 2007 @ 15:59:55
  Author: pcdavid
    Path: /cvsroot/fractal/web/xml/root/fscript

Modified: index.xml

* Added example snippet of both FPath and FScript on the main FScript page.
* Added a list of current users of FPath and/or FScript on the main FScript 
page.


-----------+
 index.xml |   84 ++++++++++++++++++++++++++++++++++++++++++++++++------------
 1 files changed, 68 insertions(+), 16 deletions(-)


Index: web/xml/root/fscript/index.xml
diff -u web/xml/root/fscript/index.xml:1.1 web/xml/root/fscript/index.xml:1.2
--- web/xml/root/fscript/index.xml:1.1  Sun Feb 11 17:48:26 2007
+++ web/xml/root/fscript/index.xml      Tue Feb 20 15:59:55 2007
@@ -11,21 +11,74 @@
     <s1 name="FPath and FScript">
 
       <p><strong>FPath</strong> is a notation inspired
-       by <a href="http://www.w3.org/TR/xpath";>XPath</a> which makes it easy 
to
-       navigate inside Fractal architectures to discover its strucutre or 
find
-       elements (components or interfaces) which match certain criterions.
-       Compared to the direct use of the Fractal PIs, a simple FPath query 
can
-       often replace dozens of lines of Java code.</p>
+       by <a href="http://www.w3.org/TR/xpath";>XPath</a> which makes it easy 
to navigate
+       inside Fractal architectures to discover its strucutre or find 
elements
+       (components or interfaces) which match certain criterions. Compared 
to the direct
+       use of the Fractal PIs, a simple FPath query can often replace dozens 
of lines of
+       Java code. For example, the following query finds all the shared 
components in an
+       application:</p>
 
-      <p><strong>FScript</strong> is a scripting language dedicated to 
Fractal
-       components architectural reconfigurations. It builds upon FPath but 
adds
-       the possibility to define reconfiguration scripts to modify the
-       architecture of a Fractal application. Like FPath, FScript is much 
more
-       concise the direct API usage. In addition, the FScript interpreter
-       guarantees that the reconfiguration will finish and is atomic: either 
it
-       is completely and correctly applied, or not at all (in case of an
-       error).</p>
+      <source>$root/descendant-or-self::*[count(parent::*) > 1]</source>
 
+      <p><strong>FScript</strong> is a scripting language dedicated to 
Fractal
+       components architectural reconfigurations. It builds upon FPath but 
adds the
+       possibility to define reconfiguration scripts to modify the 
architecture of a
+       Fractal application. Like FPath, FScript is much more concise the 
direct API
+       usage. In addition, the FScript interpreter guarantees that the 
reconfiguration
+       will finish and is atomic: either it is completely and correctly 
applied, or not
+       at all (in case of an error).</p>
+
+      <p>The following FScript code snippet defines a reconfiguration action 
which
+       enables a cache component in a running Comanche HTTP server:</p>
+
+      <source><![CDATA[
+action enable-cache(handler) = {
+  dispatcher := $handler/child::rd;
+  if (not(cache-enabled($dispatcher))) then {
+    unbind($dispatcher/interface::h0);
+    file-handler := $handler/child::frh;
+    cache := get-or-create-cache($handler);
+    bind($dispatcher/interface::h0, $cache/interface::request-handler);
+    bind($cache/interface::handler, $file-handler/interface::rh);
+    start($cache);
+  }
+}]]></source>
+
+      <subtitle anchor="users">Users</subtitle>
+      
+      <p>Current users of FPath and/or FScript include:</p>
+      <ul>
+        <li>The <a 
href="http://picolibre.int-evry.fr/projects/cosmos";>COSMOS</a>
+          (COntext entitieS coMpositiOn and Sharing) project is a framework 
for managing
+          context information which introduces the notions of a context node 
and a context
+         processor which can be composed and assembled to form complex 
policies for
+         handling context information. The COSMOS framework is implemented 
on top of the
+         Fractal component framework with the DREAM component library. FPath 
is used in
+         COSMOS to capture sets of references to attributes or components 
that follow
+         selection criteria and simplify the configuration process.</li>
+       <li><a href="http://heim.ifi.uio.no/rouvoy/";>Romain Rouvoy</a> has 
written an
+         independent implementation of FPath (soon to be released) as part 
of his thesis.
+         He uses FPath to express structural invariants on Fractal 
architectures, using
+         an extension of the Fractal ADL. These invariants can then be 
checked either at
+         deployment time or after a dynamic reconfiguration to validate the
+         architecture.</li>
+       <li><a href="http://www2.lifl.fr/~pessemie/";>Nicolas Pessemier</a> 
uses FPath in
+         his <a href="http://fac.gforge.inria.fr/";>FAC</a> (Fractal Aspect 
Component)
+         system. FAC is an extension of Fractal to unify Component-Based 
Software
+         Development with Aspect-Oriented Software Development. FPath 
requests are used
+         to find matching join points of a give pointcut. In FAC, a pointcut 
select
+         component operations, which are represented as nodes in FPath. 
FScript is used
+         to perform the reconfiguration operations needed when weaving an 
aspect
+         component in FAC.</li>
+       <li><a href="mailto:Marc.Leger@xxxxxxxxxxxxxxxxxx";>Marc Léger</a> is 
working on
+         improving fault-tolerance in Fractal, especially in the presence of 
dynamic
+         reconfigurations. He uses FPath to specify constraints and 
invariants of Fractal
+         reconfiguration operations and to select the elements to lock when 
concurrent
+         reconfigurations are in effect. He also plans to use FScript as a 
front-end to
+         his fault-tolerant version of Fractal, as stronger guarantees can 
be offered
+         when reconfigurations are expressed in FScript rather than in 
Java.</li>
+      </ul>
+      
       <subtitle anchor="download">Download</subtitle>
 
       <p>There is no released version of FScript yet, but you can get
@@ -41,9 +94,8 @@
       <subtitle>Mailing list</subtitle>
 
       <p>Questions, comments, ideas, etc. related to FPath and FScript
-       can be posted on
-       the <a href="http://www.objectweb.org/wws/info/fractal";>Fractal 
mailing
-       list</a>.</p>
+       can be posted on the <a 
href="http://www.objectweb.org/wws/info/fractal";>Fractal
+       mailing list</a>.</p>
 
     </s1>