filmReel

A format for encoding API state flow expectations.

The filmReel specification aims to move the source of truth for how an API should behave from the service itself and into a series of linear state diagrams. This allows one to set loosely coupled and human readable expectations for an API.

By having filmReel be the source of truth for how an API should behave one can:

• Identify regressions in service logic.
• Determine whether mocks or stubs that mimic a service have become outdated.
• Aggregate data to support stateful integration tests.

filmReel concepts:

• The Frame - the JSON file where input an output expectations are set
• The Reel - the file naming system tying Frames together
• The Cut - the data sharing system allowing one Frame to pass messages to the next Frame

Example: _annotated

usr.01s.createuser.fr.json _{naming a file}

{
  "protocol": "gRPC",
  "cut": {
    "to": {
      "USER_ID": "'response'.'body'.'message'"
    }
  },
  "request": {
    "body": {
      "email": "new_user@humanmail.com"
    },
    "uri": "user_api.User/CreateUser"
  },
  "response": {
    "body": {
      "message": "created user: ${USER_ID}"
    },
    "status": 0
  }
}