perfsonar development work

Author: zurawski
Date: 2007-03-08 11:17:44 -0500 (Thu, 08 Mar 2007)
New Revision: 212

Modified:
   trunk/nmwg/schema/README.txt
Log:
Changes suggested by Nicolas.

-jason



Modified: trunk/nmwg/schema/README.txt
===================================================================
--- trunk/nmwg/schema/README.txt        2007-02-15 19:23:04 UTC (rev 211)
+++ trunk/nmwg/schema/README.txt        2007-03-08 16:17:44 UTC (rev 212)
@@ -4,7 +4,13 @@
 
 1).    Model (as detailed as possible) the interactions that will
        occur between the system and other actors (the LS, clients, 
-       other entities in pS) in XML markup.  
+       other entities in pS) in XML markup.  A simple tutorial on
+       XML can be found here:
+       
+       http://en.wikipedia.org/wiki/XML#Quick_syntax_tour
+       
+       Additionally, consult the numerous examples to get a 
+       feel of how other services have been developed using XML.
                
                - Each interaction should consist of a request 
                  and a response.  Make each interaction a separate 
@@ -25,6 +31,12 @@
                  (if it can only be 1 or two string values, name
                  them, if it is all floating point numbers, say that.
                
+                 For example if only certain 'versions' of a piece of
+                 software are acceptable, make sure to indicate which
+                 versions are acceptable:
+                 
+                 <version> software_v1 | software_v2 </version>
+                 
                - Example:
                
                Consider a system that will register it's presence to 
@@ -132,8 +144,36 @@
                *NOTE: See examples such as the rrdMA messages.         
 
 2).    Once you have your instances, fill in namespaces and make them as 
-        'correct' as possible.  Use comments to describe your intentions.
+        'correct' as possible.  Use comments to describe your intentions.  An
+       example of a namespace for the 'ping' tool would be:
+       
+       "http://ggf.org/ns/nmwg/tools/ping/2.0/";
 
+       A namespace is basically a URI meant to describe a 'unique' set
+       of objects that live in the XML world.  Assigning a new URI to a 
+       set of objects sets them aside as being in a controlled environment.
+       
+       The namespace you select does not have to correct right of the bat, we
+       will help you with this.  The important part is to select something, 
+       and then assign a 'prefix' to each element.  A prefix is used like 
this:
+       
+       <ping:subject xmlns:ping="http://ggf.org/ns/nmwg/tools/ping/2.0/"; />
+
+        We assign the namespace to the prefix 'ping' and we can then use this
+       as a shortcut to indicate membership.  It is important to also note
+       this similarity:
+       
+       <ping:subject xmlns:ping="http://ggf.org/ns/nmwg/tools/ping/2.0/"; />
+       <foo:subject xmlns:foo="http://ggf.org/ns/nmwg/tools/ping/2.0/"; />
+       <bar:subject xmlns:bar="http://ggf.org/ns/nmwg/tools/ping/2.0/"; />    
                  
+
+       Despite having different prefixes, they all map to the same 
namespace, 
+       therefore each of these objects would be semantically (although not
+       syntactically) similar. 
+
+       Namespaces and prefixes are a complex topic, we will be there to help
+       anyone who needs it, but please make a good effort. 
+
 3).    Create a schema file, it is best to start with something simple like
        'ping.rnc' as a base.  This simple file builds off of the 
'nmbase.rnc',
        'result.rnc', 'nmtopo.rnc', 'nmtopo_v3.rnc', and 'nmtime.rnc' files 
@@ -206,4 +246,4 @@
 
-----------------------------------------------------------------------------------------
 Jason Zurawski
 

-2/15/07
+03/08/07