Distributed, Parallel Web Service Orchestration Using XSLT

Abstract

GridXSLT is an implementation of the XSLT programming language designed for distributed web service orchestration. Based on the functional semantics of the language, it compiles programs into dataflow graphs which can be efficiently executed across a collection of machines in a cluster or grid environment. Calls to web services can be made using the standard function call semantics provided by the language, and occur in parallel using the dataflow model of computation. The programmer is not required to explicitly specify the parallelism, as the details of how programs are scheduled and executed in a distributed environment are abstracted away by the runtime engine. XSLT provides a higher level programming model than many other approaches to web services composition; we explore its use here as a means of easing the task of orchestrating the interactions between services. In addition to the normal XSLT syntax, our system also supports programs written in XSLiTe, an alternative syntax we have developed which uses more concise representations of language constructs, increasing the ease of development, and bringing code readability closer to that of traditional programming languages. Our goal is to ease the construction of applications based on web services composition, such as those used in eScience and other fields in which service oriented architectures are prominent.

Specification, planning, and execution of QoS‐aware Grid workflows within the Amadeus environment

“…Most of the existing work on workflow systems may be grouped in three categories: (1) systems that are tailored for scientific workflows based on Globus [14] Grid infrastructure [3,15,16]; (2) systems for business workflows that are based on Web services-related technologies (such as SOAP, WSDL, and BPEL) [17][18][19][20]; and (3) systems for scientific workflows that use and further extend the standard Web services technologies developed for business workflows [11,16,21]. In comparison to business workflows, the distinguishing features of Grid workflows are the long execution time of compute intensive activities and the large data transfer between activities (typically the data exchange is performed via large files).…”

A Distributed Virtual Machine for Parallel Graph Reduction

“…Our virtual machine and intermediate language are part of a broader project to implement a distributed, parallel version of XSLT [12]. The use of graph reduction came about as an evolution of earlier work on compiling XSLT into dataflow graphs [13], while our stream-based implementation of network connections is intended for use as an underlying mechanism for accessing web services [14].…”

Compiler support for effective XSL transformation

“…Examples of these applications are as follows: An increasing number of Web technologies are being used in our everyday lives. These technologies often leverage XSLT to support solutions in heterogeneous environments . The maturing of technologies related to information integration has enhanced the importance of the performance and the throughput of data exchange. The requirement to transform massive datasets is also becoming increasingly common. Social networking is increasing in popularity, with individuals being grouped for specific events and sharing various types of information.…”