@article {2022:jwe, title = {A Large-scale Empirical Assessment of Web API Size Evolution}, journal = {Journal of Web Engineering}, volume = {21}, year = {2022}, month = {November}, pages = {1937{\textendash}1980}, abstract = {Like any other type of software, also Web Application Programming Interfaces (APIs) evolve over time. In the case of widely used API, introducing changes is never a trivial task, because of the risk of breaking thousands of clients relying on the API. In this paper we conduct an empirical study over a large collection of OpenAPI descriptions obtained by mining open source repositories. We measure the speed at which Web APIs change and how changes affect their size, simply defined as the number of operations. The dataset of API descriptions was collected over a period of one year and includes APIs with histories spanning across up to 7 years of commits. The main finding is that APIs tend to grow, although some do reduce their size, as shown in the case study examples included in the appendix.}, keywords = {API Evolution}, doi = {10.13052/jwe1540-9589.2167}, url = {https://ieeexplore.ieee.org/document/10246943}, author = {Fabio Di Lauro and Souhaila Serbout and Cesare Pautasso} } @conference {apiace:2022:ecsa, title = {To deprecate or to simply drop operations? An empirical study on the evolution of a large OpenAPI collection}, booktitle = {16th European Conference on Software Architecture (ECSA)}, volume = {13444}, year = {2022}, month = {September}, pages = {38-46}, publisher = {Springer}, organization = {Springer}, address = {Prague, Czech Republic}, keywords = {API Analytics, API Evolution}, doi = {doi.org/10.1007/978-3-031-16697-6_3}, author = {Fabio Di Lauro and Souhaila Serbout and Cesare Pautasso} } @conference {2022:icsa, title = {Web APIs Structures and Data Models Analysis}, booktitle = {19th IEEE International Conference on Software Architecture (ICSA 2022)}, year = {2022}, month = {March}, publisher = {IEEE}, organization = {IEEE}, address = {Honululu, Hawaii}, abstract = {Microservice architectures emphasize keeping components small, to foster autonomy, low coupling, and independent evolution. In this large-scale empirical study, we measure the size of Web API specifications mined from open source repositories. These APIs are modeled using the OpenAPI Specification (OAS), which, in addition to documenting the offered operations, also contain schemas definitions for the data exchanged with the API request and response message payloads. This study has as a goal to build empirical knowledge about: (1) How big and diverse are real-world web APIs both in terms of their operations and data, (2) How different API structures use and reuse schema definitions. By mining public software repositories on Github, we gathered 42,194 valid OAS specifications published between 2014-2021. }, keywords = {API Analytics, API Size, OpenAPI}, author = {Souhaila Serbout and Fabio Di Lauro and Cesare Pautasso} } @conference {2021:icwe:api-evolution, title = {Towards Large-scale Empirical Assessment of Web APIs Evolution}, booktitle = {21st International Conference on Web Engineering (ICWE2021)}, year = {2021}, month = {May}, pages = {124-138}, publisher = {Springer}, organization = {Springer}, address = {Biarritz, France}, abstract = {Web Application Programming Interfaces (APIs) decouple the internal implementation of a service from its consumers which can reuse and compose them to rapidly build new applications. Many Web APIs are described with the OpenAPI Specification (OAS). The goal of our research is to check the feasibility of using API descriptions found in public open source repositories to study how APIs evolve over time. To do so, we collected a large dataset of OAS documents by crawling open source repositories, we parsed the corresponding metadata and measured the API size in order to extract a simple model to track the lifecycle of API artifacts and observe common evolution behaviors. Our preliminary results indicate that only a subset of the APIs changes, but as opposed to the expectation that APIs should only grow to maintain backward compatibility we also detected a number of APIs with a more variable history. We also study the stability of API artifacts over time and whether APIs are more or less likely to change as they age.}, keywords = {API Evolution, OpenAPI, Web API}, doi = {10.1007/978-3-030-74296-6_10}, author = {Fabio Di Lauro and Souhaila Serbout and Cesare Pautasso} } @conference {2021:icwe:liquid-wasm, title = {WebAssembly Modules as Lightweight Containers for Liquid IoT Applications}, booktitle = {21st International Conference on Web Engineering (ICWE2021)}, year = {2021}, month = {May}, publisher = {Springer}, organization = {Springer}, address = {Biarritz, France}, abstract = {Going all the way to IoT with web technologies opens up the door to isomorphic IoT system architectures, which deliver flexible deployment and live migration of code between any device in the overall system. In this vision paper, we propose using WebAssembly to implement lightweight containers and deliver the required portability. Our long-term vision is to use the technology to support developers of liquid IoT applications offering seamless, hassle-free use of multiple devices.}, keywords = {containers, Internet of Things, IoT, Light-weight containers, liquid software, Web of Things, WebAssemly, WoT}, author = {Niko M{\"a}kitalo and Tommi Mikkonen and Cesare Pautasso and Victor Bankowski and Paulius Daubaris and Risto Mikkola and Oleg Beletski} } @proceedings {icwe:2015:rmc, title = {Rapid Mashup Development Tools}, volume = {591}, year = {2016}, publisher = {Springer}, address = {Rotterdam, The Netherlands}, keywords = {mashup tools}, doi = {10.1007/978-3-319-28727-0}, url = {http://mashup.inf.usi.ch/challenge/2015/}, editor = {Florian Daniel and Cesare Pautasso} } @proceedings {2016:icwe:workshop, title = {Web Engineering Workshops}, volume = {9881}, year = {2016}, month = {June}, pages = {209}, publisher = {Springer}, address = {Lugano, Switzerland}, keywords = {Web engineering}, issn = {978-3-319-46962-1}, doi = {10.1007/978-3-319-46963-8}, url = {http://icwe2016.webengineering.org}, author = {Sven Casteleyn and Peter Dolog and Cesare Pautasso} } @conference {naturalmash:vlhcc:2013, title = {Natural End-User Development of Web Mashups}, booktitle = {IEEE Symposium on Visual Languages and Human-Centric Computing (VL/HCC 2013)}, year = {2013}, month = {September}, pages = {111 - 118 }, publisher = {IEEE}, organization = {IEEE}, address = {San Jose, CA, USA}, abstract = {End-User Development (EUD) can be exploited on the Web, where users have the opportunity to create niche {\textquotedblleft}Web Mashup{\textquotedblright} applications as a means to address their long tail of situational needs in different domains of application. In this paper, we describe the design and evaluation of NaturalMash, an innovative EUD system for mashups. NaturalMash provides a high level of expressive power while it is still usable by non-professional users. This clearly distinguishes NaturalMash from existing mashup EUD tools that are either too limited or highly specialized for inexperienced users. The NaturalMash user interface efficiently combines different techniques such as live programming, natural language programming, What You See Is What You Get (WYSIWYG), and Programming by Demonstration (PbD). The design of NaturalMash adopts a formative evaluation approach, and has completed two design and evaluation iterations. The paper reports the results of the last formative evaluation and discusses the implications of the findings. The results are promising and suggest that the proposed system has a short and gentle learning curve and enables even non-professional users to rapidly build useful mashups.}, keywords = {end-user software engineering, natural language processing, NaturalMash, service composition, Web mashups}, doi = {10.1109/VLHCC.2013.6645253}, author = {Saeed Aghaee and Cesare Pautasso and Antonella De Angeli} } @inproceedings {scube:icse:2012, title = {Research challenges on service technology foundations}, year = {2012}, month = {June}, pages = {27-33}, abstract = {This work gives an overview of the future research challenges on enabling technologies for service-based applications that have been identified in the network of excellence S-Cube. Service-based applications comprise three layers: business processes, service compositions and services and service infrastructures. The goal of this work is to present a roadmap for future research in technologies for software and system services.}, keywords = {adaptation models, biological system modeling, business process management, business transactions, cloud computing, computational modeling, formal models, KPIs, liquid computing, monitoring, monitoring and adaptation, nature-inspired approches, quality of service, s-cube, service composition, service infrastructures, service networks, service oriented architectures, service oriented computing, service technology foundations}, doi = {10.1109/S-Cube.2012.6225505}, author = {Dimka Karastoyanova and Manuel Carro and Dragan Ivanovic and Claudia Di Napoli and Maurizio Giordano and Zsolt Nem{\'e}th and Cesare Pautasso} } @article {5453330, title = {Information Quality in Mashups}, journal = {Internet Computing}, volume = {14}, number = {4}, year = {2010}, month = {July-August}, pages = {14-22}, abstract = {Modern Web 2.0 applications are characterized by high user involvement: users receive support for creating content and annotations as well as "composing" applications using content and functions from third parties. This latter phenomenon is known as Web mashups and is gaining popularity even with users who have few programming skills, raising a set of peculiar information quality issues. Assessing a mashup{\textquoteright}s quality, especially the information it provides, requires understanding how the mashup has been developed, how its components look alike, and how quality propagates from basic components to the final mashup application.}, keywords = {component quality, information quality, mashup patterns, mashups, quality metrics, Web 2.0 applications, Web mashups}, issn = {1089-7801}, doi = {10.1109/MIC.2010.60}, author = {Cinzia Cappiello and Florian Daniel and Maristella Matera and Cesare Pautasso} } @conference {jopera:2005:escience, title = {Publishing Persistent Grid Computations as WS Resources}, booktitle = {1st IEEE International Conference on e-Science and Grid Computing (e-Science 2005)}, year = {2005}, month = {December}, publisher = {IEEE}, organization = {IEEE}, address = {Melbourne, Australia}, abstract = {Grid services can be composed into processes, providing a high level definition of the computations involved in terms of their data exchanges and control flow dependencies. We show how processes themselves can be efficiently published as Grid services by mapping the persistent state of the process executions to standard compliant interfaces as defined by the Web Services Resource Framework (WS-RF). Mapping processes to resources is a fundamental step to enable recursive Grid service composition, where composite Grid services are themselves published as services. This gives processes a standardized and wellunderstood interface that enables their management, monitoring, steering and adaptation. Additionally it eases their reusability and simplifies integration into existing Grid applications and portals. In order to determine the mapping{\textquoteright}s overhead, we include the results of a comprehensive performance evaluation.}, keywords = {grid computing, JOpera, scientific workflow management}, doi = {10.1109/E-SCIENCE.2005.67}, author = {Thomas Heinis and Cesare Pautasso and Oliver Deak and Gustavo Alonso} }