Pact vs OpenAPI: Choosing the right foundation for your API testing strategy

The article explores the pros and cons of using Pact versus OpenAPI for API testing strategies, highlighting the complexities and benefits associated with each approach. Pact, a consumer-driven contract testing method, offers comprehensive testing but involves significant setup and maintenance complexity, often outweighing its benefits for many teams. It is particularly suited for large organizations with internal microservices where failures could be catastrophic. In contrast, OpenAPI, a provider-driven API specification, is easier to implement and maintain, reducing setup complexity and coordination needs while providing a single contract for all consumers, making it a preferable choice for teams with external API consumers. The article also discusses the potential of combining OpenAPI with the Arazzo workflow specification to enhance end-to-end testing across multiple APIs. Ultimately, the decision between Pact and OpenAPI should be based on team structure, consumer profile, resource availability, and API complexity, with OpenAPI being more manageable for smaller or resource-constrained teams.