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OGSA-DAI Data Publisher

Overview

Many organisations require access to large amounts of data held in a variety of formats in a geographically diverse set of places. One goal of Grid-related developments in data management has been to improve the availability of this information. In a business context this involves making privately held data available to selected partners and Grid middleware solutions have been developed to help address this need. An example of such a solution is OGSA-DAI. In order for Grid middleware such as OGSA-DAI to be effectively exploited within commercial and industrial sectors, the process of publishing data should be both straightforward and repeatable so that these can be deployed upon multiple systems with only a small training overhead. As an example of improving an existing middleware solution, the OGSA-DAI Data Publisher provides a GUI-based application for installing and configuring an OGSA-DAI server and the data resources it exposes.

The OGSA-DAI Data Publisher is published under the open source Apache 2 licence, and is available for download.

High Level Architecture

The publisher is deployed via an intuitive GUI-based installer. Once the publisher has set up and configured an OGSA-DAI installation, access to the data is supported via the standard OGSA-DAI data access interfaces.

The publisher goes through a number of steps.

1.      Install Prerequisites
In order to install OGSA-DAI a number of prerequisites are required, e.g. a Web services container and database drivers compatible with the data resources to be exposed. Typically these are downloaded and installed separately. That requirement is removed by bundling the pre-requisites with the publisher. The publisher installs only the required pre-requisites for the type of install.

2.      Install OGSA-DAI
In order to expose data resources, the interface of OGSA-DAI is used. The installation of OGSA-DAI using the appropriate pre-requisites is managed by the publisher.

3.      Expose Data Resources
In order to expose data, OGSA-DAI is configured according to the user specifications. This includes configuring the security of the OGSA-DAI server and the exposed data resource to ensure only authorized clients can access the data. This final step publishes the data the database holds which is then accessible via the Java client toolkit of OGSA-DAI or any client that can communicate with OGSA-DAI Web services.

Usage Scenario

This component can be used to aid in the deployment of a Grid middleware solution at an existing organisation. For example, suppose a chain of shops want to integrate their existing store-specific accounting systems to reduce costs. In order to do this, the stores' procedures will be augmented with central systems for taking orders and generating reports. In order to achieve this, the individual stores must publish their databases. Given that, in most cases, the people who install the computing resources at the stores will know little about Grid middleware, having a simple, easy-to-use, tool for exposing their databases is very useful.

Dependencies

As the component is an installer, it includes all the pre-requisite middleware and other third-party components required to set OGSA-DAI up. This primarily includes a Web services container plus database drivers. It also installs OGSA-DAI v3.2.2 and its pre-requisites to provide the publishing support. Java is required to run the installer.

Interface

The installer has a simple graphical interface. Once the publisher has installed OGSA-DAI and exposed data resources, the data can be accessed via standard Web service interfaces or the client toolkit interfaces of OGSA-DAI v3.2.2.

Further Details

  • Related Design Patterns: Data Source Publisher
  • Related Common Capabilities: Access to a Remote Data Source
  • Related Technical Requirements: Accessing Data from Different Locations
  • Release Date: May 2008
  • License: Apache 2
  • Contact: mailto:beingrid(at)epcc.ed.ac.uk
  • Development Status: Beta
  • Programming Language(s): Java 1.4
  • Supported Operating Systems: Platform Independent
  • Supported or Required Middleware: OGSA-DAI 3.2.2
  • Other Dependencies: Java 1.4, Globus Toolkit v4, Apache Tomcat (bundled)
  • Installation Guide: OGSA-DAIDATASOURCEPUBLISHERDESIGN.DOC
  • User Guide: OGSA-DAIDATASOURCEPUBLISHERREADME.TXT

Download

The component can be downloaded from here.