EnquireLabs Code Project

The EnquireLabs code project is an opportunity for our team to see how you approach technical problem solving and code writing. It is not meant to be a comprehensive examination of your programming skills; rather, a small challenge with enough nuance to offer a glimpse into your thought process, and set a foundation for broader discussion. After you've completed the project, we will schedule a follow up conversation to discuss your solution.

The Project: The Question Machine

The Question Machine is effectively a simplified version of a core feature our product provides; it uses built-in contextual triggers to present questions to end users (today, millions of consumers interact with questions we display each month). You’ll be demonstrating your approach to a customer-facing problem/solution, and delivering a basis for conversation about what could be done to expand on the solution.

The Question Machine is a simple server that listens to requests from a client over a TCP connection to present a series of questions, and subsequently gather responses to those questions. Which questions are asked depends on the properties of the client session. The goal of the project is to make the tests in test/question_machine_test.exs pass using the Elixir standard library.

Messages between the clients and the Question Machine server are Erlang terms encoded as binary. Clients should initialize a session by sending an initialize message with the properties of the session:

%{
  "action" => "initialize",
  "props" => %{
    "country" => "us"
  }
}

The Question Machine responds with an identifier for the session that the client uses to make subsequent requests:

%{
  "status" => "ok",
  "session" => SOME_SESSION_ID
}

The client could then, for example, ask for the next question like so:

%{
  "action" => "next_question",
  "session" => SOME_SESSION_ID
}

The Questions

Below is the list of questions, their responses to be presented to the client, and the conditions for presenting them. Clients must respond to the questions in the order presented by the Question Machine (e.g. if question 2 is the next question, they can't answer question 3 before question 2). A question should only be presented if the properties of the session match the conditions of the question. The Question Machine should only accept a response that is found in the responses list.

1: How did you hear about us?

Online Ad
Podcast
From a friend

conditions: this question is always presented

2: Why did you purchase this product today?

Quality is great
Price is right
This is a gift
Recommended by a friend

conditions: this question is presented if the "products_purchased" property of the session includes 1, 5, or 9

3: What is your favorite podcast?

All About Your Brain
True Murders
Space and Time

conditions: this question is presented if the "country" session property is "us" OR the "new_customer" property is "true"

The Tests

The tests are found in test/question_machine_test.exs and can be run with the standard mix task: mix test.

Submitting Your Solution

Fork this repository and implement your solution. Then, add chasselschwert as a read-only collaborator to your fork, and email curt@enquirelabs.com to let us know it’s ready for review.

We hope you find this project interesting and look forward to discussing your solution!

– EnquireLabs

jowrjowr/code-project