Reusable and Extensible Fault Tolerance for RESTful Applications

Abstract—Despite the simplicity and scalability benefits of REST, rendering RESTful web applications fault-tolerant requires that the programmer write vast amounts of non-trivial, ad-hoc code. Network volatility, HTTP server errors, service outages—all require custom fault handling code, whose effective implementation requires considerable programming expertise and effort. To provide a systematic and principled ap-proach to handling faults in RESTful applications, we present FT-REST—an architectural framework for specifying fault tolerance functionality declaratively and then translating these specifications into platform-specific code. FT-REST encapsu-lates fault tolerance strategies in XML-based specifications and compiles them to modules that reify the requisite fault tolerance. To validate our approach, we have applied FT-REST to enhance several realistic RESTful applications to withstand the faults described in their FT-REST specifications. As REST is said to apply verbs (HTTP commands) to nouns (URIs), FT-REST enhances this conceptual model with adverbs that render REST reliable via reusable and extensible fault tolerance. Keywords-fault tolerance, web services, REST, software reusability, software extensibilit

JeroMF: A Software Development Framework for Building Distributed Applications Based on Microservices and JeroMQ

This report describes a project involving the design, implementation, and testing of a software development framework, called JeroMF, that can help developers create scalable distributed applications based on a microservice architecture and that uses JeroMQ (a native Java implementation of ZeroMQ) for message passing. JeroMF provides an execution framework and extensible components for implementing processes, services, communication channels, messages, communication statistics, and encryption. Applications built with JeroMF do not require a message broker or any other middleware processes. However, they may include an optional Service Registry that can facilitate for service discovery and secure communications. The Service Registry itself was implemented with JeroMF and is included as part of the JeroMF distribution. Thorough unit, integration and system test cases exist for every component of JeroMF. For validation, JeroMF was used to re-design and re-implement a distributed health-care application with 13 separate types of services and very strict security requirements

On the Modularization of ExplorViz towards Collaborative Open Source Development

Software systems evolve over their lifetime. Changing conditions such as requirements or customer requests make it inevitable for developers to perform adjustments to the underlying code base. Especially in the context of open source software where everybody can contribute, demands can change over time and new user groups may be addressed. In particular, research software is often not structured with a maintainable and extensible architecture. In combination with obsolescent technologies, this is a challenging task for developers, especially, when students are involved. In this paper, we report on the modularization process and architecture of our open source research project ExplorViz towards a microservice architecture, which facilitates a collaborative development process for both researchers and students. We describe the modularization measures and present how we solved occurring issues and enhanced our development process. Afterwards, we illustrate our modularization approach with our modernized, extensible software system architecture and highlight the improved collaborative development process. Finally, we present a proof-of-concept implementation featuring several developed extensions in terms of architecture and extensibility

Benchmarking Buffer Size in IoT Devices Deploying REST HTTP

A few potential IoT communication protocols at the application layer have been proposed, including MQTT, CoAP and REST HTTP, with the latter being the protocol of choice for software developers due to its compatibility with the existing systems. We present a theoretical model of the expected buffer size on the REST HTTP client buffer in IoT devices under lossy wireless conditions, and validate the study experimentally. The results show that increasing the buffer size in IoT devices does not always improve performance in lossy environments, hence demonstrating the importance of benchmarking the buffer size in IoT systems deploying REST HTTP.Comment: This paper is uploaded here for research community, thus it is for non-commercial purpose

Service Composition for IP Smart Object using Realtime Web Protocols: Concept and Research Challenges

The Internet of Things (IoT) refers to a world-wide network of interconnected physical things using standardized communication protocols. Recent development of Internet Protocol (IP) stacks for resource-constrained devices unveils a possibility for the future IoT based on the stable and scalable IP technology much like today's Internet of computers. One important question remains: how can data and events (denoted as services) introduced by a variety of IP networked things be exchanged and aggregated e ciently in various application domains. Because the true value of IoT lies in the interaction of several services from physical things, answers to this question are essential to support a rapid creation of new IoT smart and ubiquitous applications. The problem is known as service composition. This article explains the practicability of the future full-IP IoT with realtime Web protocols to formally state the problem of service composition for IP smart objects, provides literature review, and discusses its research challenges

SEF-SCC: Software engineering framework for service and cloud computing

© Springer International Publishing AG, part of Springer Nature 2018. Service computing and cloud computing have emerged to address the need for more flexible and cost-efficient computing systems where software is delivered as a service. To make this more resilient and reliable, we need to adopt software engineering (SE) principles and best practices that have existed for the last 40 years or so. Therefore, this chapter proposes a Software Engineering Framework for Service and Cloud Computing (SEF-SCC) to address the need for a systematic approach to design and develop robust, resilient, and reusable services. This chapter presents SEF-SCC methods, techniques, and a systematic engineering process supporting the development of service-oriented software systems and software as a service paradigms. SEF-SCC has been successfully validated for the past 10 years based on a large-scale case study on British Energy Power and Energy Trading (BEPET). Ideas and concepts suggested in this chapter are equally applicable to all distributed computing environments including Fog and Edge Computing paradigms