A Geospatial Web Services Composition Framework Supporting Real-Time Status Monitoring

et al. 2015

Annals of GIS

Collaborative geoprocessing models have become one of the major solutions to significantly enhance the capacity to derive knowledge over a network, which are critical for the support of comprehensive analyses in a virtual geographic environment (VGE). With the emergence and growing maturity of the cloud computing infrastructure, a cloud-based platform for collaborative geoprocessing models promises to provide a pattern for the next generation of geoprocessing collaboration in the GIS realm. However, the problems with the existing collaborative geoprocessing models remain numerous, including the following: heterogeneity in description specifications hinders different geoprocessing services in collaborative work; the heterogeneity in messages mechanisms makes the cooperation among the geoprocessing services difficult and an integrated geoprocessing model framework centring on the collaborative model's lifecycle is absent. To address these problems, this article proposes a cloud-based framework for building, executing and sharing collaborative models called GeoSquare: (1) a lifecycle model was designed for convenient and flexible collaborative geoprocessing; (2) a collaboration mechanism was implemented to solve specification heterogeneity; (3) a collaboration method and its proxy were used to resolve the heterogeneity in message communication and (4) to acquire better scalability, some elastic cloud features were utilized in the framework. A GeoSquare prototype was implemented on the Microsoft Azure Cloud to demonstrate the applicability and availability. Results show that users can build, execute, publish and share collaborative geoprocessing models with high efficiency in GeoSquare. GeoSquare provides a novel collaborative geoprocessing pattern enabling further geographic research in a cloud infrastructure.

Section: Introductionmentioning

confidence: 99%

GeoSquare: collaborative geoprocessing models’ building, execution and sharing on Azure Cloud

You

et al. 2015

Annals of GIS

“…The Web Services Business Process Execution Language (WS‐BPEL) was brought into geoprocessing to transform models to executable workflows (Zhao et al ; Schäffer and Foerster ). Based on WS‐BPEL, a series of geoprocessing service chaining tools (Gui et al ; Wu et al ; Sun et al ; You et al ) were designed and developed to compose isolated geoprocessing services. These tools are all based on Rich Client Platform (RCP) technologies that are highly dependent on client‐side operating systems and have non‐trivial requirements of client‐side computing resources.…”

Section: Related Workmentioning

confidence: 99%

An Extension Mechanism to Verify, Constrain and Enhance Geoprocessing Workflows Invocation

et al. 2015

Transactions in GIS

Geospatial web service composition is a promising means for processing and analyzing geospatial data in distributed computing environments. However, convenient and effective approaches for assisting the invocation of geoprocessing workflows are still missing. Invocation errors frustrate users and eventually impact the popularity and application of geoprocessing workflows due to their complexity, inadequate description, constraints, and prompts for input/output parameters, workflow models, and their components. This article proposes an extension method for easy invocation of geoprocessing workflows to solve these problems. The proposed method facilitates the generation of Graphical User Interfaces (GUIs) and invocation messages, for human-computer interaction and client-workflow interaction respectively, by supplementing verification and constraints for workflow descriptions. Furthermore, by providing descriptive information, constraint mechanisms, and visualization functions, this approach enhances human-computer interactivity during invocation. An exemplary user case demonstrates the feasibility of the method.

“…However, current research focuses on the structures of service composition and the description of communication modes rather than the description of data exchanged during GIService invocation [18]. For example, to support status monitoring for geoprocessing services, the proxy-based extension method was proposed [19]. SimpledataTpe used to describe texts and numbers already supported by WSDL by conventional data types.…”

Section: Introductionmentioning

confidence: 99%

Extending WSDL for describing complex geodata in GIS service

Gao

2014 the Third International Conference on Agro-Geoinformatics

You

et al. 2014

Web Services Description Language (WSDL) is an XML-based specification for describing the functionalities provided by web services [1], and widely-adopted in the IT industry. However, the message types defined in WSDL for interoperation are insufficient when describe complex data (such as, geodata) by using conventional data types in many application scenarios. For example, geodata (such as, a digital image captured through remote sensing technologies) is usually described and located simply as an URL string. Since important metadata information for description and verification are missing, neither providers nor users have good experiences with the current GIServices described in WSDL. In this paper, we extend the WSDL specification to support description of complex geodata. This extended WSDL is more pragmatic and effective than the standard WSDL in GIService-specific scenarios.