API Server templating using variables

Various ways to define API servers in the spec including variables

  servers:
    - url: 'http://example.com/api'
      description: Test server (just for example)
    - url: '/api'
    - url: '{protocol}://dev.com/api/{version}'
      variables:
        protocol:
          description: Protocol (with enum)
          default: https
          enum:
            - http
            - https
        version:
          description: API Version (without enum)
          default: v1
    - url: '{protocol}://{environment}.example.com/{version}'
      variables:
        environment:
          default: api    # Production server
          description: >
            Server choices:
            * `api` Production (this is the default).
            * `api.qa` QA server.
            * `api.dev` Development server.
          enum:
            - api      # Production server
            - api.dev  # Development server
            - api.qa   # Testing server
        protocol:
          default: https
          enum:
            - http
            - https
        version:
          default: v2
          enum:
            - v1
            - v2