Creating a web-service using perfSONAR base

From GEANT2-JRA1 Wiki

To create a schema and a java web-service (starting from perfSONAR base) making use of that schema, you need the following

1. Create the schema and the XML instances. Follow the procedure below:
   • http://anonsvn.internet2.edu/svn/nmwg/trunk/nmwg/schema/README.txt
     
   • The java implementation of the schema can be found at: http://anonsvn.internet2.edu/svn/nmwg/trunk/nmwg/java/
     
   • Now you got a schema!
2. The XML message are received by the requestHandler that will convert each elements of the XML message into NMWG objects. The RequestHandler class is a generic class, where you don't have to change anything.
   • Request handler: http://anonsvn.internet2.edu/svn/perfsonar/trunk/perfsonar/src/org/perfsonar/service/web/RequestHandler.java

   • To allow the requestHandler to convert your XML elements into NMWG you need to ensure that all the elements you used are defined. Please check the list of existing elements: http://anonsvn.internet2.edu/svn/nmwg/trunk/nmwg/java/objects.config (make sure it's up to date; take a look at the java packages; this file can be updated automatically using the script http://anonsvn.internet2.edu/svn/perfsonar/trunk/perfsonar/src/obs.pl).
   • If element isn't defined yet, you need to create it following the examples provided (around a day of work if you have never done this).
3. The requestHandler, after having converted the elements into NMWG objects, call a messageHandler. There is one messageHandler per type of message. You need thus to create a new messageHandler for the messages you are exchanging. Following the example of the RRD MA, it will take you few minutes to do so.
4. Message handler for SetuDataRequest message: http://anonsvn.internet2.edu/svn/perfsonar/trunk/perfsonar/src/org/perfsonar/commons/messages/SetupDataRequest.java
   • The message handler classes must be located in http://anonsvn.internet2.edu/svn/perfsonar/trunk/perfsonar/src/org/perfsonar/commons/messages/
5. The messageHandler will call your serviceEngine. The serviceEngine is the part that contains all the intelligence of the service (fetch the data, perform actions on an archive or on a measurement tool).
6. When testing your service, you need to create a conf/service.property document to take into effect the message types you have been creating.
   • To do so, the class names of message handlers (representing message types) must be put in the config file conf/service.properties. Examples of service.properties can be found at http://anonsvn.internet2.edu/svn/perfsonar/trunk/perfsonar/conf/
   • The file should include the list of messages that your service will use Example for RRD MA: service.ma.message_types=MetadataKeyRequest,SetupDataRequest,MeasurementArchiveStoreRequest,EchoRequest,LookupInfoRequest
   • Note that once releasedm the service.conf is created automatically by the configuration scripts.

Please note that The description refers to the current (getting old) svn structure. New svn structure is being prepared and hopefully will be the official one soon (so far the proposal can be found in svn branch).