HAPI is a public REST Web API directory which stores the discovered REST Web APIs by our APIDiscoverer thus allowing developers to browse them and download their corresponding OpenAPI specifications. We have also developed MashapeDiscoverer, a proof-of-concept to show how the API call examples can be derived from other sources like available examples in the API documentation (in this specific case, from APIs in the Mashape marketplace, a documentation portal with over 2,000 APIs) by using Selenium to crawl the documentation pages and generate their correspondent OpenAPI specs.

HAPI is also an open source community-driven project which invites developers to contribute to the directory. Following the GitHub pull-based development model, anyone can add new APIs by sending pull requests. Developers can also propose changes to existing APIs. A change may involve fixing an OpenAPI specification (e.g., correcting a parameter type) or adding new features (e.g., endpoints or parameters).

Additionally, we have created the external-sources folder which contains links to other initiatives aiming at discovering and sharing OpenAPI specs, namely:

• APIs.guru: an open source directory of OpenAPI specifications.
• APIs.io: an experimental API Search service to help discover APIs on the web.

• Hamza Ed-douibi
• Javier Canovas
• Jordi Cabot

Hamza, Javier and Jordi are currently members of SOM, a research team of IN3-UOC.