Zipmex Backend Challenge

challenge.md

Zipmex Backend Challenge

Welcome to the Zipmex backend challenge! Thanks for attempting it, we wish you good luck!

We prefer well-thought out, quality code over quick-and-dirty solutions. So - please take your time, if you need it.

Instructions

• Create an server application in your language/framework of choice.
• Write an algorithm that will take a JSON object structured like Appendix 1 Input and transform it into the structure shown under Appendix 2 Output. In other words, the algorithm will place "children" objects under the correct "parent" objects.
• Add a single endpoint that takes the unstructured JSON object as parameter and responds with the structured JSON object.

Guidelines

• Please use Elixir, Scala or NodeJS.
• Do not forget to write comprehensive tests.
• Do not forget to write documentation.
• Have some fun!

Submission

• Please submit via a git format-patch. Send your patch to the hiring team.
• Please keep track of the number of hours spent on this challenge and send along with your submission.

Deliverables

• As a reviewer, I can run your tests with a simple command.
• As a reviewer, I can boot your application locally and call the endpoint.
• As a reviewer, I can find clear documentation on how to check for the above two deliverables.

Appendix 1 Input

{"0":
  [{"id": 10,
    "title": "House",
    "level": 0,
    "children": [],
    "parent_id": null}],
 "1":
  [{"id": 12,
    "title": "Red Roof",
    "level": 1,
    "children": [],
    "parent_id": 10},
   {"id": 18,
    "title": "Blue Roof",
    "level": 1,
    "children": [],
    "parent_id": 10},
   {"id": 13,
    "title": "Wall",
    "level": 1,
    "children": [],
    "parent_id": 10}],
 "2":
  [{"id": 17,
    "title": "Blue Window",
    "level": 2,
    "children": [],
    "parent_id": 12},
   {"id": 16,
    "title": "Door",
    "level": 2,
    "children": [],
    "parent_id": 13},
   {"id": 15,
    "title": "Red Window",
    "level": 2,
    "children": [],
    "parent_id": 12}]}

Appendix 2 Output

[{"id": 10,
  "title": "House",
  "level": 0,
  "children":
   [{"id": 12,
     "title": "Red Roof",
     "level": 1,
     "children":
      [{"id": 17,
        "title": "Blue Window",
        "level": 2,
        "children": [],
        "parent_id": 12},
       {"id": 15,
        "title": "Red Window",
        "level": 2,
        "children": [],
        "parent_id": 12}],
     "parent_id": 10},
    {"id": 18,
     "title": "Blue Roof",
     "level": 1,
     "children": [],
     "parent_id": 10},
    {"id": 13,
     "title": "Wall",
     "level": 1,
     "children":
      [{"id": 16,
        "title": "Door",
        "level": 2,
        "children": [],
        "parent_id": 13}],
     "parent_id": 10}],
  "parent_id": null}]