@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} }