NGS JSDL Portal
Summary
The JSDL portal (formerly known as the JSDL Application Repository) is a single interface to a repository of personal and shared JSDL application templates for job submission and monitoring, and different remote file systems for data staging to and from various resources.
Users benefit from the immediate access to shared expertise, artefacts and configuration captured in 'ready to run' job templates. They also benefit from being able to stage data between different resources.
Download
A live deployment of the JSDL Applications Repository
is available from the NGS.
If you would like to deploy the JSDL Applications Repository elsewhere, please get in touch.
System Requirements
- Java 1.5+
- Ant 1.7+
- Transactional database
- Java Servlet container (e.g. Tomcat 5.5). Note, a full J2EE Application server is not required.
Further information
- Homepage
- Documentation
- Licence: modified BSD
- Known issues
- Support website
- Further support is available from the NGS helpdesk
Developers
The JSDL Applications Repository is developed by the National Grid Service.
What can it do?
The JSDL portal provides a repository for authoring, sharing and publishing application descriptions defined in JSDL (Job Submission Description Language). Users can browse the available applications by categories of interest (e.g. physics, tutorials, chemistry, etc.) and subsequently select, 'tweak' and save shared templates for personal use.
The JSDL portal also provides a single interface to a selection of different remote file systems, including Srb, GridFtp, Ftp, and Sftp. This facilitates file operations, file browsing and data transfer between the different file systems. In addition, file and directory selections in the portal can be used to compile the data-staging requirements of an application (e.g. compiling the JSDL, data-staging element set).
How does it work?
The portal GUI allows graphical authoring of a JSDL document. As the user interacts with the GUI, the JSDL document is continuously updated and modified in the background. At any time, the user can save an application description. The portal uses object-relational mapping techniques to persist an equivalent-object representation of the JSDL into a database, allowing a user to retrieve, modify and re-submit the application whenever required.
A user can browse and interact with different remote file systems (currently Srb, GridFtp, Ftp, Sftp) and make file and directory selections in order to compile a list of data-staging requirements for an application. This information is used to update the JSDL, data-staging element set (e.g. recording source URI and any associated information, such as target file systems on the execution host). To do this, the portal implements Commons Virtual File System (VFS) extensions to Srb, GridFtp, Ftp, and Sftp, which facilitate file operations, file browsing and data transfers between the different file systems (via byte IO).
The portal reads the JSDL document and (optionally) performs the required data staging prior to submitting the application (e.g. staging input and data files from each source URI to the target host). Following staging, the portal submits the job to the underlying middleware, allowing subsequent status monitoring. The Java implementation of SAGA (currently in development) will be used for this purpose. The aim is to support different middleware as required (GT2, GT4, GridSam and, possibly, gLite).
Work is under way to support for the newly proposed JSDL Parameter Sweep extensions, which allow a single JSDL job template to describe multiple (parametric) jobs. Indeed, the JSDL parametric requirements have been gathered throughout portal development and have been directly fed back into the JSDL parameter sweep specification.
![[RSS]](/images/xml.png)
© The University of Southampton on behalf of OMII-UK. All Rights Reserved. |
