Just a very quick example swagger.json file to get started w/ Swagger and Open API Specification.
I created the file for my talk on 1/19/17. It includes a couple of example paths: one "get", one "post." It also includes a simple security definition for header based "api_key" authentication.
Swagger.json tested across Swagger Editor and Swagger UI. I wanted to make sure I had a very basic working copy before expanding.