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Greenie.app

Greenie.app is an online "Greenie Board" for carrier-based virtual squadrons, especially squadrons that operate in Digital Combat Simulator: World. Squadrons can add passes manually or by uploading dcs.log files, and track the performance of their pilots.

Greenie.app consists of an API back-end, written in Ruby on Rails (this repository) and a tightly-coupled front-end, written in TypeScript and Vue.js. Along with these two processes, the website also uses a GoodJob process to execute background tasks, and a separate instance of the Rails server to send and receive data via WebSockets (Action Cable).

Limitations

The DCS: Supercarrier add-on is a work-in-progress. Currently, logging of LSO grades is sporadic and not all passes are guaranteed to result in a grade being logged. Furthermore, these grades are not associated with the pilot who made the pass, so Greenie.app has to "guess" which pilot flew the pass by associating the LSO grades with nearby "landing" events. Obviously, if the pass was a bolter or waveoff, no landing event is logged, and the pass is not associated with a pilot.

For this reason, proper logging of a squadron's passes requires a hands-on approach. Upload the dcs.log soon after flying your mission or carrier quals, and then compare the resulting passes with your real LSO's notes. Edit, move, or remove passes as needed.

You can also use the website without uploading dcs.log files at all. Simply have your real paddles (or their assistant) keep the website open while your pilots are making their passes. The LSO will be able to quickly log the grades for each pass. You can also record your missions to track logs and input the grades later.

Development

Installation and Running

Greenie.app required Ruby 3.3, PostgreSQL, and Redis. (If you use Homebrew, you can install those dependencies with brew install.) After cloning the repository, run bundle install to install all gem requirements. Run rails db:create db:migrate to create the development database.

Run the development server with rails server. Note that you will need to also run the front-end, the GoodJob host, and the WebSockets server in order to use the complete website. The development server also assumes a Mailcatcher process is running on port 1025 to receive emails sent in development. (Mailcatcher is not part of the Gemfile and should be gem installed manually.)

An example Foreman script that accomplishes all of this:

backend: cd Backend && rvm 3.3.6@greenie exec rails server
frontend: cd Frontend && yarn serve
workers: cd Backend && rvm 3.3.6@greenie exec bundle exec good_job start
anycable: cd Backend && rvm 3.3.6@greenie exec anycable
ws: cd Backend && rvm 3.3.6@greenie exec bin/anycable-go --port=8080
mail: mailcatcher -f

(This script assumes that the back-end is checked out into a folder called "Backend", the front-end into a folder called "Frontend", that you use RVM to manage gemsets).

Documentation

Comprehensive API documentation can be generated by running rake yard. HTML docs are generated into the doc/ directory.

Testing

Unit tests can be run with rspec spec. End-to-end testing is also implemented using Cypress; you will need the front-end checked out to run E2E tests as well. An example Foreman script that launches all necessary processes and starts the E2E test application:

backend: cd Backend && rvm 3.3.6@greenie exec rails server -e cypress -b localhost
frontend: cd Frontend && yarn run test:e2e
workers: cd Backend && RAILS_ENV=cypress rvm 3.3.6@greenie exec bundle exec good_job start
anycable: cd Backend && RAILS_ENV=cypress rvm 3.3.6@greenie exec anycable
ws: cd Backend && rvm 3.3.6@greenie exec bin/anycable-go --port=8080

Deployment

The application is deployed on Fly.io automatically after CI completes, with a GitHub Action. The fly.toml file contains the architecture for the production environment: an app server, a GoodJob worker server, a Redis cluster, and a PostgreSQL database cluster.

The Rails processes run on a separate Fly.io cluster from the AnyCable processes. An nginx cluster reverse-proxies requests for /cable to the AnyCable process, and all other requests to the Rails process.

Architecture

Data Model

The core class of Greenie.app is the {Squadron}. Each Squadron has only a single user account, whose username and password is shared by all squadron members who have permission to add, edit, and remove passes.

A Squadron has zero or more {Pass}es. Each Pass records the time and location of the pass, its grade and score, which wire was caught, etc. Each Pass is linked to a {Pilot}. Pilots are uniquely identified by name and have no other attributes.

The {LogfileProcessor} class parses dcs.log files and scans them for LSO grades. When logs are uploaded, {Logfile} records are created, and the GoodJob job processes them by calling LogfileProcessor.

Authorization

Authentication is handled by Devise. The {Squadron} class is the user model for Devise, and users are authenticated by the squadron's username and password.

Front-end authorization state is handled using JSON Web Tokens. Upon logging in, the front-end is given a JWT that is used as a bearer token for subsequent authorized reuqests.