Red Pill Routes

This program helps Tank and Cypher to parse the data from the red_pill challenge and get it into their system.

Getting started

docker build -f Dockerfile -t red_pill_routes .
# run the parser
docker run -v (pwd):/app red_pill_routes:latest

# or get a shell for development
docker run -it --rm -v (pwd):/app red_pill_routes:latest /bin/bash
# then you can run the script
./parser.rb
# or run an individual test
ruby test/route_test.rb
# or run all tests
rake test

Notes

Overview

A Loader is responsible to fetch data from a source (e.g. getting and unpacking the ZIP from the server).
A Database uses such a loader to retrieve the files and then uses this content to calculate the routes.
The Database::Aggregator merges multiple databases into one while fulfilling the same interface as Database::Base.
The Transmitter is responsible for sending a database's content to the Distribusion server.

Timezones

We assume every timezone to be UTC (+00:00) unless specified differently. In lib/lib.rb, we set the environment variable for Ruby's default timezone, so using Time.new uses UTC.

Stretches

Stretch represents a part of a route. In the data retrieved from the sources, the connections between a route start and end node were always sorted. Yet, one would assume, that the order might get scrambled up eventually.
For example in loopholes we have stretches in the following order: ["gamma -> theta", "theta -> lambda"] for the first route. To also allow to find these stretches in reverse order, one can use Stretch::order to bring them in the right sequence. This algorithm is very limited at the moment, but can be extended.

Decisions & Future work

I chose minitest over rspec to keep dependencies low
I chose to use downloaded versions of the source data as fixtures for the tests.
We could/should write much more tests.
Depending on the stability of the input data, we should add more validations during parsing, so we detect faulty data files (e.g. we are only checking for the correct node name in Sentinel).
Some of the parsing operations (such as joining/denormalizing) could be done with a helper library or a real database.
We should not store credentials in the code (as seen in Transmitter). Here we should add a secret storage.

motine / red_pill_routes