As distribution models of information systems are moving to XaaS paradigms, microservices architectures are rapidly emerging, having the RESTful principles as the API model of choice. In this context, the term of API Economy is being used to describe the increasing movement of the industries in order to take advantage of exposing their APIs as part of their service offering and expand its business model. Currently, the industry is adopting standard specifications such as Ope-nAPI to model the APIs in a standard way following the RESTful principles; this shift has supported the proliferation of API execution platforms (API Gateways) that allow the XaaS to optimize their costs. However, from a business point of view, modeling offering plans of those APIs is mainly done ad-hoc (or in a platform-dependent way) since no standard model has been proposed. This lack of standardization hinders the creation of API governance tools in order to provide and automate the management of business models in the XaaS industry. This work presents a systematic analysis of 69 XaaS in the industry that offer RESTful APIs as part of their business model. Specifically, we review in detail the plans that are part of the XaaS offerings that could be used as a first step to identify the requirements for the creation of an expressive governance model of realistic RESTful APIs. Additionally, we provide an open dataset in order to enable further analysis in this research line.

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As software architecture design is evolving to a microservice paradigm, RESTful APIs are being established as the preferred choice to build applications. In such a scenario, there is a shift towards a growing market of APIs where providers ofer diferent service levels with tailored limitations typically based on the cost.In this context, while there are well established standards to describe the functional elements of APIs (such as the OpenAPI Speciication), having a standard model for Service Level Agreements (SLAs) for APIs may boost an open ecosystem of tools that would represent an improvement for the industry by automating certain tasks during the development such as: SLA-aware scafolding, SLA-aware testing, or SLA-aware requesters.Unfortunately, despite there have been several proposals to describe SLAs for software in general and web services in particular during the past decades, there is an actual lack of a widely used standard due to the complex landscape of concepts surrounding the notion of SLAs and the multiple perspectives that can be addressed.In this paper, we aim to analyze the landscape for SLAs for APIs in two diferent directions: i) Clarifying the SLA-driven API development lifecycle: its activities and participants; 2) Developing a catalog of relevant concepts and an ulterior prioritization based on diferent perspectives from both Industry and Academia. As a main result, we present a scored list of concepts that paves the way to establish a concrete road-map for a standard industry-aligned speciication to describe SLAs in APIs.

This paper reports our experience in flipping a second-year undergraduate course on software architecture and integration, taught in the second course of a Software Engineering degree. We compare the application of the flippedclassroom methodology with a traditional methodology. Our study encompasses two academic courses, in the years 2017 and 2018, and involves a total number of 434 students and 6 lecturers, placing this among the largest studies on flipped-classroom to date. The paper also reports on the production of the videos used with the flipped-classroom methodology, recorded by the lecturers in informal settings, and provides several lessons learned in this regard. The results of the study, backed by a solid statistical analysis of the data, demonstrate the suitability of the flipped-classroom methodology for laboratory sessions in the subject course. Among other results, our analysis concluded that students had on average 24 more minutes per session to solve in-class exercises with the flipped-classroom methodology; more than 70% of the students considered that the quantity, duration and didactic content of the videos were (very) appropriate; and 9 out of every 10 students would prefer this methodology in the laboratory sessions of future courses rather than a traditional face-to-face approach.

As software architecture design is evolving to a microservice paradigm, RESTful APIs are being established as the preferred choice to build applications. In such a scenario, there is a shift towards a growing market of APIs where providers ofer diferent service levels with tailored limitations typically based on the cost. In such a context, while there are well-established standards to describe the functional elements of APIs (such as the OpenAPI Speciication), having a standard model for Service Level Agreements (SLAs) for APIs may boost an open ecosystem of tools that would represent an improvement for the industry by automating certain tasks during the development.In this paper, we introduce Governify for APIs, an ecosystem of tools aimed to support the user during the SLA-Driven RESTful APIs' development process. Namely, an SLA Editor, an SLA Engine and an SLA Instrumentation Library. We also present a fully operational SLA-Driven API Gateway built on the top of our ecosystem of tools. To evaluate our proposal, we used three sources for gathering validation feedback: industry, teaching and research.• Website: links.governify.io/link/GovernifyForAPIs • Video: links.governify.io/link/GovernifyForAPIsVideo CCS CONCEPTS• Information systems → RESTful web services; • Software and its engineering → Extra-functional properties; System description languages.