HI!MVC: Hierarchical MVC Framework for WEB Applications

This paper presents Hi!MVC, a framework for developing high interactive web applications with a MVC Architecture. Nowadays, to manage, extend and correct web applications can be difficult due to the navigational paradigm they are based on. Hi!MVC framework helps to make these tasks easier. This framework allows building a web based interface, generating each page from the objects that represent its state. Every class to be showed in the interface is associated with two entities: its html representation (view) and its interactions in the view manager (controller). The whole html page is generated by composition of views according to the composition relationship of objects. Interactions between user and application are managed by the controller associated to the view which shows interaction elements (links or forms). Hi!MVC allows building web interface in a hierarchical and distributed way. There are other frameworks and APIs offering MVC architectures to web applications, but we think that they are not applying exactly the same concepts. While they keep on basing their architectures on the navigational paradigm we are offering a new point of view based on an innovator hierarchical model. First, we present the main ideas of our proposal. Next, we expose how to implement it using different Java technologies. Finally, we make a first approach to our hierarchical MVC model. We also compare shortly our proposal with the previously cited technologies

A Survey of the Selenium Ecosystem

Selenium is often considered the de-facto standard framework for end-to-end web testing nowadays. It allows practitioners to drive web browsers (such as Chrome, Firefox, Edge, or Opera) in an automated fashion using different language bindings (such as Java, Python, or JavaScript, among others). The term ecosystem, referring to the open-source software domain, includes various components, tools, and other interrelated elements sharing the same technological background. This article presents a descriptive survey aimed to understand how the community uses Selenium and its ecosystem. This survey is structured in seven categories: Selenium foundations, test development, system under test, test infrastructure, other frameworks, community, and personal experience. In light of the current state of Selenium, we analyze future challenges and opportunities around it.This work has been supported by the European Commission under the H2020 project "MICADO" (GA-822717), by the Government of Spain through the project "BugBirth" (RTI2018-101963-B-100), by the Regional Government of Madrid (CM) through the project "EDGEDATA-CM" (P2018/TCS-4499) cofunded by FSE & FEDER, and by the project "Analytics using sensor data for FlatCity" (MINECO/ERDF, EU) funded in part by the Spanish Agencia Estatal de Investigación (AEI) under Grant TIN2016-77158-C4-1-R and in part by the European Regional Development Fund (ERDF)

Authentication, Authorization, and Accounting in WebRTC PaaS Infrastructures: The Case of Kurento

Server infrastructures for Web Real-Time Communications (WebRTC) are useful for creating rich applications. Developers commonly use them to access capabilities such as group communications, archiving, and transcoding. Kurento is an open source project that provides a WebRTC media server and a platform as a service (PaaS) cloud built on top. The authors present its API and analyze different security models for it, investigating the suitability of using simple access control lists and capability-based security schemes to provide authorization.This work is supported by the European Commission under projects FI-WARE FP7-2011-ICT-FI, GA-285248, and NUBOMEDIA FP7-ICT-2013-1.6, GA-610576

A systematic review on cloud testing

A systematic literature review is presented that surveyed the topic of cloud testing over the period (2012-2017). Cloud testing can refer either to testing cloud-based systems (testing of the cloud), or to leveraging the cloud for testing purposes (testing in the cloud): both approaches (and their combination into testing of the cloud in the cloud) have drawn research interest. An extensive paper search was conducted by both automated query of popular digital libraries and snowballing, which resulted into the final selection of 147 primary studies. Along the survey a framework has been incrementally derived that classifies cloud testing research along six main areas and their topics. The paper includes a detailed analysis of the selected primary studies to identify trends and gaps, as well as an extensive report of the state of art as it emerges by answering the identified Research Questions. We find that cloud testing is an active research field, although not all topics have received so far enough attention, and conclude by presenting the most relevant open research challenges for each area of the classification framework.This paper describes research work mostly undertaken in the context of the European Project H2020 731535: ElasTest. This work has also been partially supported by: the Italian MIUR PRIN 2015 Project: GAUSS; the Regional Government of Madrid (CM) under project Cloud4BigData (S2013/ICE-2894) cofunded by FSE & FEDER; and the Spanish Government under project LERNIM (RTC-2016-4674-7) cofunded by the Ministry of Economy and Competitiveness, FEDER & AEI

ElasTest, an open-source platform to ease end-to-end testing

The demand for larger and more interconnected software systems is constantly increasing, but the ability of developers to satisfy this demand is not evolving accordingly. The most limiting factor is software Verification and Validation (V&V), which typically requires very costly and complex testing processes. The objective of the ElasTest project is to significantly improve the efficiency and effectiveness of the testing process and, with it, the overall quality of large software systems. To that aim, ElasTest provides an integrated solution for end-to-end test automation along the development life cycle, including test case management, deployment, instrumentation, and monitoring for different kind of applications, including web and mobile.This work has been supported by the European Commission under project ElasTest (H2020-ICT-10-2016, GA-731535); by the Regional Government of Madrid (CM) under project Cloud4BigData (S2013/ICE-2894) cofunded by FSE & FEDER; and Spanish Government under project LERNIM (RTC-2016-4674-7) cofunded by the Ministry of Economy and Competitiveness, FEDER & AEI

Understanding and estimating quality of experience in WebRTC applications

WebRTC comprises a set of technologies and standards that provide real-time communication with web browsers, simplifying the embedding of voice and video communication in web applications and mobile devices. The perceived quality of WebRTC communication can be measured using quality of experience (QoE) indicators. QoE is defined as the degree of delight or annoyance of the user with an application or service. This paper is focused on the QoE assessment of WebRTC-based applications and its contribution is threefold. First, an analysis of how WebRTC topologies affect the quality perceived by users is provided. Second, a group of Key Performance Indicators for estimating the QoE of WebRTC users is proposed. Finally, a systematic survey of the literature on QoE assessment in the WebRTC arena is presented

Kurento: The Swiss Army Knife of WebRTC Media Servers

In this article we introduce Kurento, an open source WebRTC media server and a set of client APIs intended to simplify the development of applications with rich media capabilities for the Web and smartphone platforms. Kurento features include group communications, transcoding, recording, mixing, broadcasting and routing of audiovisual flows, but also provides advanced media processing capabilities such as computer vision and augmented reality. It is based on a modular architecture, which makes it possible for developers to extend and customize its native capabilities with third-party media processing algorithms. Thanks to all of this, Kurento can be a powerful tool for Web developers who may find natural programming with its Java and JavaScript APIs following the traditional three-tiered Web development model

Practical evaluation of VMAF perceptual video quality for WebRTC applications

WebRTC is the umbrella term for several emergent technologies aimed to exchange real-time media in the Web. Like other media-related services, the perceived quality of WebRTC communication can be measured using Quality of Experience (QoE) indicators. QoE assessment methods can be classified as subjective (users' evaluation scores) or objective (models computed as a function of different parameters). In this paper, we focus on VMAF (Video Multi-method Assessment Fusion), which is an emergent full-reference objective video quality assessment model developed by Netflix. VMAF is typically used to assess video streaming services. This paper evaluates the use of VMAF in a different type of application: WebRTC. To that aim, we present a practical use case built on the top of well-known open source technologies, such as JUnit, Selenium, Docker, and FFmpeg. In addition to VMAF, we also calculate other objective QoE video metrics such as Visual Information Fidelity in the pixel domain (VIFp), Structural Similarity (SSIM), or Peak Signal-to-Noise Ratio (PSNR) applied to a WebRTC communication in different network conditions in terms of packet loss. Finally, we compare these objective results with a subjective evaluation using a Mean Opinion Score (MOS) scale to the same WebRTC streams. As a result, we found a strong correlation of the subjective video quality perceived in WebRTC video calls with the objective results computed with VMAF and VIFp in comparison with SSIM and PSNR and their variants.This work has been supported by the European Commission under project ElasTest (H2020-ICT-10-2016, GA-731535); by the Regional Government of Madrid (CM) under project EDGEDATA-CM (P2018/TCS-4499) cofunded by FSE and FEDER; by the Spanish Government under projects LERNIM (RTC-2016-4674-7) and BugBirth (RTI2018-101963-B-I00) cofunded by the Ministry of Economy and Competitiveness, FEDER and AEI

Designing and evaluating the usability of an API for real-time multimedia services in the Internet

In the last few years, multimedia technologies in general, and Real-Time multimedia Communications (RTC) in particular, are becoming mainstream among WWW and smartphone developers, who have an increasing interest in richer media capabilities for creating their applications. The engineering literature proposing novel algorithms, protocols and architectures for managing and processing multimedia information is currently overwhelming. However, most of these results do not arrive to applications due to the lack of simple and usable APIs. Interestingly, in this context in which APIs are the critical ingredient for reaching wide developer audiences, the scientific literature about multimedia APIs and their usability is scarce. In this paper we try to contribute to fill this gap by proposing the RTC Media API: a novel type of API designed with the aim of making simple for developers the use of latest trends in RTC multimedia including WebRTC, Video Content Analysis or Augmented Reality. We provide a specification of such API and discuss how it satisfies a set of design requirements including programming-language agnosticism, adaptation to cloud environments, support to multisensory multimedia, etc. After that, we describe an implementation of such an API that has been created in the context of the Kurento open source software project, and present a study evaluating the API usability performed in a group of more than 40 professional developers distributed worldwide. In the light of the obtained results, we conclude that the usability of the API is adequate across the main development activities (i.e. API learning, code creation and code maintenance), with an average usability score of 3.39 over 5 in a Likert scale, and that this result is robust with respect to developers' profiles, cultures, professional experiences and preferred programming languages