Requirements

Movies in MovieDB should have one of the following workflow states:

• draft
• pending
• published
• declined

A movie always begins as a draft and then transitions through the states as it's getting reviewed. This could be a typical state flow for a movie:

CopystateDiagram-v2
    [*] --> draft
    draft --> pending
    pending --> declined: Reason
    declined --> pending
    pending --> published

Change the visibility rules (Consul powers) so:

• All users can see published movies of other users.
• All users can see the movies they created themselves, regardless of their state.
• An admin can see movies from other users that are published, pending or declined.

We will now add some additional controls to transition a movie between states:

• When a user views one of her draft or declined movies, she sees a button Submit on the movie's show view. This changes the movie's state to pending.
• When an admin opens a pending movie by any user, she sees two buttons Publish and Decline.
• Before the admin may decline a movie, she is required to enter a declining reason. The declining reason should be entered in a form like the other forms in your app, with the same form round trip and controller handling. Consider whether you want to implement this inside an existing :movies resource or in a new one just for the declining form.
• In addition, when an admin edits a movie by any user, she can choose any state from a select box, regardless of the movie's current state. Note that any transition constraints and callbacks will not be enforced when the #state is set directly. We only do this to allow admins to correct user errors.

Implementation

Make two implementations of the requirements above:

• Using only Ruby/Rails and no state machine gems
• Using a gem like rails_state_machine Show archive.org snapshot

Make sure that you have tests for all the changes you make.

Tip

factory_bot offers traits Show archive.org snapshot to define variants of a factory. Your default factory should create records in a state that is useful for the vast majority of tests.