Pull repo and run sudo docker build --tag ufo_hotspots:2.3 . inside project directory
Run sudo docker-compose up
Navigate in a browser to localhost:8080 to see the app render this file
For the next step, I tried to accomplish inside the docker container but I could not get my app to connect to the mysql database due to this error: Mysql2::Error::ConnectionError: Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock'
Stop all containers
Start mysql (if installed) and run rails server
From the app directory, run bin/hotspot_locator.rb <relative path to csv file> to load ufo sightings and get json results back.
A dump of the json results from my tests is included. The file is json_response.json
Overview
Environment setup: I had a brand new linux partition I wanted to use for this (my only other personal dev environment was windows and I have had issues developing in ruby there) but I am not a huge linux guy so that presented some challenges. I needed to install quite a few things, but I didn't count that as time working on the app. The only notable technology I used besides the obvious (ruby/rails/mysql) was Visual Studio Code with my favorite extensions.
Initializing the app: I just ran "rails new ufo_hotspots -d mysql".
Test driven developement: I decided to use TDD, even though it would slow me down, because I would rather write solid, correct code than ship a bug. I ended up only writing two services along with a command line script that uses them, and a controller to render this file so the web app actually did something.
The services I created are:
hotspot_locator.rb: a service that handles all the distance finding and retrieval of sightings within range of a hotspot.
csv_reader.rb: a service that could read a csv file and parse the contents, and return them as ufo sightings that hotspot_locator would understand.
Database schema
My db schema only has one table, ufo_sightings with the columns specified by the coding challenge.
Challenges
I had trouble getting access for the app to mysql, because the user could only login with sudo.
My tests could not find my service classes for some reason and I had to restart spring to fix it.
TDD is time-consuming, so I didn't accomplish as much as I wanted. What remains to be done are things I am confident I could do with a bit more time. Web applications are what I have done the most in Ruby, so controllers, routes, erb templates and models are all within my wheelhouse.
I accidentally lost a lot of changes at one point by running the wrong git command... luckily I still had my files open in my IDE and could resave them. I committed each change separately again so that my workflow would still be evident in my git history.
At first I tried using the Geometry gem, but it gave me errors and I didn't want to risk losing a lot of time going down a rabit hole, so I scrapped it.
I wasn't sure what styleguide to follow (seattle or standard).
I ran into a lot of issues with getting docker-compose to play nicely with my environment.
Assumptions
One degree in lattitude or longitude is 69 miles, even though it actually varies slightly (according to google).
Next steps (assume these would be done with TDD)
Create a controller and controller action to handle ufo_sighting data post requests, call the HotspotLocator and return the result as JSON. Add routes to routes.rb.
Generate a controller action for an API to retrieve stored ufo sighting withing range of hotspots.
Generate a ufo_sightings controller for basic CRUD operations, with assciated views.
Generate a controller, index action, and view to show ufo sightings as they come in. Implement an auto refresh with javascript to make it real-time.
Do more, and more, and more...
Feedback
This was a fun and challenging code assessment. The CSV parsing was particulary challenging and I didn't have time to do a very good job. I handled the varying formats by simply skipping rows that my code didn't like, but that's something I would have liked to solve better. I am sure there is an existing solution I could use somewhere.
Docker is a big topic and I enjoyed getting more hands on with it.
If you would like, I have a side project where I am building a Progressive Web App using React, Rails, and Service-Workers here: https://github.com/WriterZephos/StoicQuoteBook. I have temporarily made that repo public.
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