DeliverToStreamServlet

The DeliverToStreamServlet is a servlet which can be deployed within a Web services container and receives outputs from the deliverToStream activity.

The servlet must be installed in the same Web services container as OGSA-DAI.

Installation

To install the DeliverToStreamServlet:

1. Edit the file

   CONTAINER/webapps/webapp/WEB-INF/web.xml
   

   • where webapp is the name of the Web Application in your container under which OGSA-DAI is deployed. Typically this is:
     • axis for OGSA-DAI WSI
     • wsrf for OGSA-DAI WSRF
   • Add the following <servlet> description at the bottom of the list of <servlet> descriptions:

     <servlet>
       <servlet-name>DeliverToStreamServlet</servlet-name>
       <display-name>OGSA-DAI Deliver To Stream Servlet</display-name>
       <servlet-class>
         uk.org.ogsadai.activity.delivery.DeliverToStreamServlet
       </servlet-class>
     </servlet>
     

   • Add the following <servlet-mapping> description at the bottom of the list of <servlet-mapping> descriptions:

     <servlet-mapping>
       <servlet-name>DeliverToStreamServlet</servlet-name>
       <url-pattern>/servlet/DeliverToStreamServlet</url-pattern>
     </servlet-mapping>
     

2. Shutdown and restart your Web services container.

Usage

When the deliverToStream activity is executed then data will be streamed to the following URL:

http://host:port/webapp/servlet/DeliverToStreamServlet?url=
service&resourceId=resource&sessionId=session&streamId=stream

where

• host is your container host.
• port is your container port number.
• webapp is the name of the Web Application in your container under which OGSA-DAI is deployed. Typically this is:
  • axis for OGSA-DAI WSI
  • wsrf for OGSA-DAI WSRF
• service is the relative path to your service.
• resourceId is the name of the data service resource to which the stream belongs i.e. the data service resource to which you send a request containing the deliverToStream activity.
• sessionId is the ID of the session within which the request containing the deliverToStream activity was executed. This will be contained in the response from the service when the request was origially submitted.
• streamId is the value of the name attribute of the deliverToStream activity.

For example:

http://localhost:8080/axis/servlet/DeliverToStreamServlet?url=
ogsadai/DataService&resourceId=One&sessionId=
session-ogsadai-106c06ab61c&streamId=delivery

http://localhost:8080/wsrf/servlet/DeliverToStreamServlet?url=
ogsadai/DataService&resourceId=One&sessionId=
session-ogsadai-106c06ab61c&streamId=delivery