README

About this application

The objective of this project is to display the launch data provided by the SpaceX API, the following information was used:

• Last Launch
• Next Launch
• Pastes Launches
• Upcoming Launches

Prerequisites

This project was made in:

• Ruby 2.7.1
• Rails 6.1.3.1

Enabling A/B test

This step is optional:The project has an A/B test made at Google Optimize that changes the theme randomly according to the accesses, to this work it's necessary to add the following line to the host file of your operating system:

127.0.0.1 spacex-kasper.com

After that, you may need to restart your computer for the change to take effect.

Running the project

Access the project root folder from the terminal and run:

rails s

If you performed the configuration step of the host file described at the beginning, after the application starts you can access it by http://spacex-kasper.com:3000/. In this situation the A/B test will be working and the application may appear to you in the original way or as DarkMode.

Running the test suite

To run the tests it is necessary to have RSpec installed. Open the terminal in the project's root folder and run:

 bundle install
 rails generate rspec:install

After this, just execute the command at the terminal to check the tests:

 rspec

All tests are in the this file:

/spacex_launch/spec/controllers/lauch_controller_spec.rb

For mocking the HTTP request was used WebMock

Implementation points

To communicate with the Spacex API was created a SpacexApi in the folder app/controllers/services/, the gem HTTParty was used to perform the requests.

This class has four methods, where each of them is responsible for launches information ( next, past, upcoming, latest ), past and upcoming methods use the same endpoint, where it is possible to perform queries to customize the result, for this, was created the methodgetParams that return a hash with the necessary filters and data for querying and displaying the results.

The controller LaunchController consumes data from SpacexApi and then make them available to the view, it has a similar structure, with four methods, the implementation is very simple, since the bureaucratic part is in charge of the service. =)

As the application has only one page, all methods have been instantiated in the index method, so when the index route is accessed, all data is available to be use.

And finally, in the view we have four sections to display the results, two upper sections where unitary launches are displayed, last and next, and at the bottom, a table with the last and next five launches.

A Helper was created to handle the dates (formatter_simple_date). Bootstrap was used to make the look more pleasant. =)

Metrics from A/B test (Only from the first few days)

In three days of testing, accessing the application from a single machine, we can compile the data below:

Page view of the experiment.

Session of experiment

This table shows us very interesting data, accesses in the DarkMode variant have much longer sessions and with higher bounce rates.

In this other table with some more information, Google Optimize suggested that the DarkMode variant is 100% likely to be the best combination.