Web API development and integration for microservice functionality in web applications

Pro gradu -työssä mallinnetaan ja kehitetään mallin mukainen toteutus mikropalvelu-arkkitehtuuriin perustuvasta laajennuksesta olemassaolevaan verkkosovellukseen, joka tutkimuksen mukaan mahdollistaa verkkosovelluksen loppukäyttäjien hyödyntämisen sovelluksen jatkokehittämisessä monoliittisen arkkitehtuurin sovelluksia joustavammin. Pääasiallinen taustateoria sisältää Participative Design ja Design Science -teorioita.This paper presents a model for web application programming interface (API) that uses the microservice architecture to enable and support end-user feature development. The study follows the design-science paradigm of information systems research. Participatory design stands as one ISR-based theory and definitions of user types are derived from that. Web application definitions and web application development methods are also explored to some extent. The study will also present an implementation of the presented web API design that is then analyzed and reviewed in comparison with other similar API design patterns. Implementation consists of application extensions, web API and microservice based feature extensions, written in Javascript using Node.js runtime environment and the host application uses ASP.NET MVC. The implementation reveals benefits of microservice architecture regarding scalability, extensibility and utilization of the user-base in application feature development. Extending an existing application also emphasizes the importance of communication protocol specifications and related knowledge