OmiseGO Backend Challenge

backend_challenge.md

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

Keep track of the amount of hours you spend working on this challenge and send it with your submission to thibault@omisego.co.

Part 1

Instructions

In the first part of this assignment, you will need to create a Phoenix application.

• The application needs to have an endpoint that takes a body containing a JSON document following the format presented below under Appendix 1 Input as one of the parameters.
• Upon receiving a call, the Phoenix application will need to run an algorithm to turn the input into the format shown under Appendix 2 Output. Basically, the JSON document needs to be re-organized by moving children into the correct parents.
• The application should then return the formatted document in a JSON document.

Algorithm Details

You will need to write an algorithm in Elixir in your Phoenix application to transform the JSON input below into the JSON output. Each child should be placed in the children array of its parent (as defined by the parent_id).

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}]}

Appending 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}]

Part 2

Instructions

Use the GitHub Search API with pagination to find all the repositories that match the query elixir. Display results 10 by 10 in a view in the Phoenix application you built in Step 1. Results should be displayed in a table (it doesn't have to look good) and pagination should be fully functional on the front-end side.

Guidelines

• Don't forget documentation.
• The pagination between your local application and the GitHub results should be synced.