Back-end

Made with:

Tested on Ubuntu 18.04.2 LTS.

Requirements:

Python3
sqlite3 (this should be a built-in Python library)
flask (pip install flask)
gunicorn (for production - pip install gunicorn)
docker & docker compose (for production - see below for guide)

Instructions for deployment

Clone the repo https://github.com/PApostol/RoboticHoover.git.
Navigate to ~/RoboticHoover/ and open a terminal.

Depending on the state of your system, you might need to run the following commands on a terminal:

sudo apt-get install python3-mysqldb
pip install mysqlclient

For development:

Execute python3 main.py on terminal.
Flask will serve the API on localhost:5000.

For production:

Execute sudo docker-compose -f prod.docker-compose.yml up --build --remove-orphans.
Docker will spin a back-end container and serve the API on localhost.

For data input, execute a curl command in a terminal (include port 5000 if in development):

Input:

curl -i -d '{ "roomSize" : [5, 5], "coords" : [1, 2], "patches" : [ [1, 0], [2, 2], [2, 3] ], "instructions" : "NNESEESWNWW" }' -X POST http://localhost/api/execute/

Output:

{"coords": [1, 3], "patches": 1}

The output is shown on the terminal. Both input and output are saved in the storage/ folder as text files with a timestamp. They are also saved in an SQL database in database/.

Docker:

-To install:

Docker CE: https://docs.docker.com/install/linux/docker-ce/ubuntu/

Docker-Compose: https://draculaservers.com/tutorials/install-use-docker-compose-ubuntu-18-04/

Terminal commands:

-view existing containers: sudo docker ps -a

-stop all containers: sudo docker kill $(sudo docker ps -q)

-remove all containers: sudo docker rm $(sudo docker ps -a -q)

-remove all docker images: sudo docker rmi $(sudo docker images -q)

Notes:

Docker will download and handle all requirements for its containers to run properly. If you're using a proxy, Docker might stuck!
To double check that the back-end is running, navigate to localhost/api/test/ in production, or localhost:5000/api/test/ in development.

Yoti SDK Back-end test

Introduction

You will write a service that navigates a imaginary robotic hoover (much like a Roomba) through an equally imaginary room based on:

room dimensions as X and Y coordinates, identifying the top right corner of the room rectangle. This room is divided up in a grid based on these dimensions; a room that has dimensions X: 5 and Y: 5 has 5 columns and 5 rows, so 25 possible hoover positions. The bottom left corner is the point of origin for our coordinate system, so as the room contains all coordinates its bottom left corner is defined by X: 0 and Y: 0.
locations of patches of dirt, also defined by X and Y coordinates identifying the bottom left corner of those grid positions.
an initial hoover position (X and Y coordinates like patches of dirt)
driving instructions (as cardinal directions where e.g. N and E mean "go north" and "go east" respectively)

The room will be rectangular, has no obstacles (except the room walls), no doors and all locations in the room will be clean (hoovering has no effect) except for the locations of the patches of dirt presented in the program input.

Placing the hoover on a patch of dirt ("hoovering") removes the patch of dirt so that patch is then clean for the remainder of the program run. The hoover is always on - there is no need to enable it.

Driving into a wall has no effect (the robot skids in place).

Goal

The goal of the service is to take the room dimensions, the locations of the dirt patches, the hoover location and the driving instructions as input and to then output the following:

The final hoover position (X, Y)
The number of patches of dirt the robot cleaned up

The service must persist every input and output to a database.

Input

Program input will be received in a json payload with the format described here.

Example:

{
  "roomSize" : [5, 5],
  "coords" : [1, 2],
  "patches" : [
    [1, 0],
    [2, 2],
    [2, 3]
  ],
  "instructions" : "NNESEESWNWW"
}

Output

Service output should be returned as a json payload.

Example (matching the input above):

{
  "coords" : [1, 3],
  "patches" : 1
}

Where coords are the final coordinates of the hoover and patches is the number of cleaned patches.

Deliverable

The service:

is a web service
must run on Mac OS X or Linux (x86-64)
must be written in any of the languages that we support with our SDKs (Java, C#, Python, Ruby, PHP, Node, Go)
can make use of any existing open source libraries that don't directly address the problem statement (use your best judgement).

Send us:

The full source code, including any code written which is not part of the normal program run (scripts, tests)
Clear instructions on how to obtain and run the program
Please provide any deliverables and instructions using a public Github (or similar) Repository as several people will need to inspect the solution

Evaluation

The point of the exercise is for us to see some of the code you wrote (and should be proud of).

We will especially consider:

Code organisation
Quality
Readability
Actually solving the problem

This test is based on the following gist https://gist.github.com/alirussell/9a519e07128b7eafcb50

PApostol / RoboticHoover