Master Thesis Andre Landgraf

Identification of API Management Patterns from an API Provider Perspective Based on Longitudinal Data

Abstract

APIs provide the means for software engineers to co-create software systems. In today's distributed software architectures, web APIs are used to enable loose coupling of software components and services. The co-creation of software systems demands new management responsibilities such as API management. The corresponding literature is sparse and lacks standards. The goal of this thesis is to identify API management concerns and document practical solutions from an API provider perspective. The communication between the different API provider and API consumer entities is the focus of this thesis. The final outcome is a pattern catalog. The pattern catalog links detected stakeholders, concerns, and influence factors to solution approaches. Each solution approach is documented as a pattern. Overall, four stakeholders, 32 concerns, 35 pattern candidates, and 23 validated patterns are documented in this study. To achieve described objectives, this study draws from both design and behavioral science research. An extensive knowledge base grounded in literature reviews is utilized to create the foundations for this thesis. The study is evaluated and justified through 16 semi-structured interviews with API provider stakeholders. The rule of three known uses within studied cases is utilized to validate pattern candidates as patterns.

Research Questions

RQ1: What issues do API Providers face on their daily work?

RQ2: What influence factors impact the API ecosystem?

RQ3: How do API Providers manage the concerns and what is the rationale behind the solutions?