Eloit

Ranking through comparison

Summary

Eloit is a social platform aiming to rank things by comparison using Elo scores. It is a term project for Yale's CPSC 439 by Xinli, Harry, Jack, Yofti, Revant, and Kevin.

Problem

We want to address the problem of rating things in a new way. Traditionally, rating sites provide a scale of 1-10 for users to choose from, and people can see rankings based on average ratings. Of course this works, but sometimes what we want is to make comparisons and rank items that generally have similar ratings on a 1-10 scale. Maybe film A has a slightly higher average rating than film B, but 60% of people who have seen both would consider B the better one. That is because when people offer ratings they often don’t have a fair perspective in their judgment. By using other items as a reference, these ratings will have a more intuitive meaning and produce results that more accurately represent people’s preferences. Furthermore, by using a “this or that” structure, people can more easily engage with and debate the results, demonstrating another advantage over traditional ratings.

Technology Stack

Our technology stack is built around two main technologies: the open-source UI SDK Flutter on the frontend and Google's Firebase backend-as-a-service. Using the cross-platform capabilities of Flutter, our app is able to run on the following systems:

• Web (our current primary platform, hosted at https://eloit-c4540.web.app)
• iOS
• Android
• Mac

with future options for Windows and Linux versions as well. Moreover, in terms of Firebase, we use a variety of cloud functionalities, including:

• Firebase Authentication for secure registration and login
• Cloud Firestore no-SQL database for storing our basic app data
• Firebase Storage for storing images
• Firebase Hosting for deploying and hosting the website

Installation/Running

In order to run our project locally, complete the following steps:

1. Install the Flutter SDK
2. (Optional) Set up your desired emulators/devices for running
3. Execute flutter pub get in the project folder to get updated packages
4. Execute flutter run to run the project Notably, there is no particular backend setup required, as everything is cloud-based and connected via Firebase.

Project/Folder Structure

While not comprehensive, a basic outline of the folder structure of our project is as follows:

• lib conatins the majority of our structual project code
  • main.dart contains the main function that drives the application
  • models contains the database models as Dart classes
  • screens contains the code for the UI of each screen
  • services contains "backend" services, e.g. database and authentication
  • shared includes files and Flutter widgets used in muliple places across the app
• test and integration_test contains our test files
• db_help includes some Python scripts for loading categories automatically into the database and other database management tasks
• .github/workflows contains the Github Workflows described below for testing and deployment
• web, android, ios, macos, windows, and linux contain the compiled code and dependencies for each platform

CI/CD Workflow

Our project, while primarily a mobile application, has a corresponding web version that is hosted via Firebase hosting at https://eloit-c4540.web.app. On all pushes, our test.yml workflow gets the required packages using flutter pub get, tests the application according to the tests in the test and integration_test folders using flutter test, and builds the web application with flutter build web. If the push was to main (e.g. for a merged pull request), the deploy.yml workflow takes the aforementioned web build and deploys it to Firebase. Ultimately, this creates a workflow of constant testing and deployment of successful versions of main.