[back/ddd/cqs] Vehicle fleet parking management

Instructions

I have a vehicle fleet and I want to manage where every vehicle is parked.

Subject

register_vehicle.feature

Feature: Register a vehicle

    In order to follow many vehicles with my application
    As an application user
    I should be able to register my vehicle

    @critical
    Scenario: I can register a vehicle
        Given my fleet
        And a vehicle
        When I register this vehicle into my fleet
        Then this vehicle should be part of my vehicle fleet

    Scenario: I can't register same vehicle twice
        Given my fleet
        And a vehicle
        And I have registered this vehicle into my fleet
        When I try to register this vehicle into my fleet
        Then I should be informed this this vehicle has already been registered into my fleet

    Scenario: Same vehicle can belong to more than one fleet
        Given my fleet
        And the fleet of another user
        And a vehicle
        And this vehicle has been registered into the other user's fleet
        When I register this vehicle into my fleet
        Then this vehicle should be part of my vehicle fleet

park_vehicle.feature

Feature: Park a vehicle

    In order to not forget where I've parked my vehicle
    As an application user
    I should be able to indicate my vehicle location

    Background:
        Given my fleet
        And a vehicle
        And I have registered this vehicle into my fleet

    @critical
    Scenario: Successfully park a vehicle
        And a location
        When I park my vehicle at this location
        Then the known location of my vehicle should verify this location

    Scenario: Can't localize my vehicle to the same location two times in a row
        And a location
        And my vehicle has been parked into this location
        When I try to park my vehicle at this location
        Then I should be informed that my vehicle is already parked at this location

Definitions:

• Vehicle: a car, truck, motocycle, or any transportation mode that can help me to move from point A to point B on planet earth.
• Fleet: a collection a distinct vehicles.
• Location: a way to localize on planet earth, like GPS coordinates for example.

Guidelines

1. Don't use any framework at this step!
2. Prefer not using any production dependency (therefore, for javascript ramda and/or lodash can be used)
3. apply CQS & DDD principles.
4. Write corresponding bdd tests (behat, cucumber.js, ...)
5. Your code should resides into the following directory structure:

./src/
   App    # Command, Queries and corresponding handlers
   Domain # Domain model.s/structure.s and value objects
          # (classes or structures & functions if fp)
   Infra  # Implementation of repositories and every specific
          # infrastructure related implementation.s.

Tips

• Try to first write bdd/gherkin tests, then implement the code.
• Ask you: how many entities do I have? Which one aggregates every action?
• Ask you: how many Commands? Queries?
• At the moment, you don't have to persist data elsewhere than in memory.
• Here's an indication of ≈ expected number of line of codes, for implementations in php and javascript:

php

➜ cloc --exclude-dir=vendor .
      13 text files.
      13 unique files.
       2 files ignored.

github.com/AlDanial/cloc v 1.82  T=0.02 s (573.7 files/s, 23186.9 lines/s)
-------------------------------------------------------------------------------
Language                     files          blank        comment           code
-------------------------------------------------------------------------------
PHP                              9             64             48            304
Cucumber                         2              8              0             41
JSON                             1              0              0             20
-------------------------------------------------------------------------------
SUM:                            12             72             48            365
-------------------------------------------------------------------------------

javasript

➜ cloc --exclude-dir=node_modules .
      12 text files.
      12 unique files.
       3 files ignored.

github.com/AlDanial/cloc v 1.82  T=0.02 s (534.2 files/s, 14852.0 lines/s)
-------------------------------------------------------------------------------
Language                     files          blank        comment           code
-------------------------------------------------------------------------------
JavaScript                       7             37              0            175
Cucumber                         2              8              0             41
JSON                             1              0              0             17
-------------------------------------------------------------------------------
SUM:                            10             45              0            233
-------------------------------------------------------------------------------

Evaluation

• Questions (max: 5) before starting to code.
• Quality of the code.
• Please be careful to not over engineer your solution!
• Usage of good practices and modern programming language features.