Coveo Backend Coding Challenge

(inspired by https://github.com/busbud/coding-challenge-backend-c)

Requirements

Design a REST API endpoint that provides auto-complete suggestions for large cities.

• The endpoint is exposed at /suggestions
• The partial (or complete) search term is passed as a querystring parameter q
• The caller's location can optionally be supplied via querystring parameters latitude and longitude to help improve relative scores
• The endpoint returns a JSON response with an array of scored suggested matches
  • The suggestions are sorted by descending score
  • Each suggestion has a score between 0 and 1 (inclusive) indicating confidence in the suggestion (1 is most confident)
  • Each suggestion has a name which can be used to disambiguate between similarly named locations
  • Each suggestion has a latitude and longitude

"The rules"

• You can use the language and technology of your choosing. It's OK to try something new (tell us if you do), but feel free to use something you're comfortable with. We don't care if you use something we don't; the goal here is not to validate your knowledge of a particular technology.
• End result should be deployed on a public Cloud (Heroku, AWS etc. all have free tiers you can use).

Advice

• Try to design and implement your solution as you would do for real production code. Show us how you create clean, maintainable code that does awesome stuff. Build something that we'd be happy to contribute to. This is not a programming contest where dirty hacks win the game.
• Documentation and maintainability are a plus, and don't you forget those unit tests.
• We don’t want to know if you can do exactly as asked (or everybody would have the same result). We want to know what you bring to the table when working on a project, what is your secret sauce. More features? Best solution? Thinking outside the box?

Can I use a database?

If you wish, it's OK to use external systems such as a database, an Elastic index, etc. in your solution. But this is certainly not required to complete the basic requirements of the challenge. Keep in mind that our goal here is to see some code of yours; if you only implement a thin API on top of a DB we won't have much to look at.

Our advice is that if you choose to use an external search system, you had better be doing something really truly awesome with it.

Sample responses

These responses are meant to provide guidance. The exact values can vary based on the data source and scoring algorithm

Near match

GET /suggestions?q=Londo&latitude=43.70011&longitude=-79.4163

{
  "suggestions": [
    {
      "name": "London, ON, Canada",
      "latitude": "42.98339",
      "longitude": "-81.23304",
      "score": 0.9
    },
    {
      "name": "London, OH, USA",
      "latitude": "39.88645",
      "longitude": "-83.44825",
      "score": 0.5
    },
    {
      "name": "London, KY, USA",
      "latitude": "37.12898",
      "longitude": "-84.08326",
      "score": 0.5
    },
    {
      "name": "Londontowne, MD, USA",
      "latitude": "38.93345",
      "longitude": "-76.54941",
      "score": 0.3
    }
  ]
}

No match

GET /suggestions?q=SomeRandomCityInTheMiddleOfNowhere

{
  "suggestions": []
}

References

• Geonames provides city lists Canada and the USA http://download.geonames.org/export/dump/readme.txt

Getting Started

Begin by forking this repo and cloning your fork. GitHub has apps for Mac and Windows that make this easier.