Taekwondo App

Note that the app is mostly in Danish.

I made this app after discussions in my local taekwondo club on how to easily track the participation of members. That is; to be able to answer the question "have X participated sufficiently to be allowed next graduation?"

Many similar apps exists. Those I have tried either have ads, are paid or are too complex to use because of all the unnecessary functionality.

If I had spent more time I probably would have found a useful app though. The primary reason for building the app was for me to get a bit experience with app building and seeing how much the o1-preview model can help you build something from scratch.

With my extensive Python experience I decided to build the API myself and leave just the Flutter app to the o1-preview model. The experiment succeeded; I made very little tweaking of the Flutter app myself and almost everything was produced by o1-preview. I basically had the role of a product owner and just had to state the requirements clearly to the o1-preview model. The gpt directory contains the prompts I used (except for the first two that I forgot to keep). It has taken around 50 working hours in total.

Table of Contents

• Test Setup
• Design Overview
• Features
• Getting Started
  • Prerequisites
• Usage
  • Login
  • Home Screen
  • Participants Tab
  • Coach Tab
  • Admin Tab
  • Theory Tab
  • Links Tab

Test setup

A test setup is running at https://d3c06zdmscvvms.cloudfront.net/

You can test it by logging in (upper right corner) as one of the profiles below. Note that every hour at minute 0 the setup resets to a clean state and your changes will be gone.

• Admin Grandmaster ByteFist login code: OhbVrpoi
• Coach Black Belt Betty login code: VgRV5IfL
• Student Tornado Todd login code: oCLrZ3aW

Design Overview

Technologies: Python, Flutter, Dart, Amazon S3, Amazon CloudFront, Amazon Lambda, Amazon EventBridge, OpenAI o1-preview model

The app frontend is hosted on Amazon S3 and accessible thought Amazon Cloudfront. The Python backend is based on an Amazon Lambda plus a file hosted on Amazon S3. The idea is to host the non-sensitive publicly available data from the file on S3 and thus avoiding the latency that coldstarting a Lambda function incurs.

Amazon EventBridge is used to call the reset test setup action once per hour.

I didn't find a good way to cheaply host a database instance. Given the very small deployment scale I chose to go with Amazon S3 as data storage. Race conditions are avoided by restricting the allowed concurrency of the Lambda function to 1. The resulting setup has a negligible cost in the order of a few dollars a year.

I did not set up a separate DNS entry for the app as I didn't find it important. New users will be emailed the URL and authentication/login code.

Also, I have not bothered to setup any monitoring. The solution is based on solid hosted components like S3 and Lambda and the cost of not reacting quickly to a error is low.

Features

• User Authentication: Secure login using unique authentication tokens.
• Role-Based Access: Different functionalities for Participants, Coaches, and Administrators.
• Training Session Management: Create, update, and delete training sessions.
• Participation Registration: Register attendance for upcoming sessions.
• Historical Participation Data: View and analyze past participation records.
• User Management: Administrators can create, update, and delete users.
• Theory Training: Access taekwondo theory and practice with quizzes.
• External Resources: Quick links to the club's website and social media pages.

Getting Started

Prerequisites

• Flutter SDK: Ensure you have Flutter installed on your machine. You can download it from the official website.
• Dart SDK: Comes bundled with Flutter.
• IDE: I used Android Studio with Flutter and Dart plugins installed for the app and Visual Studio Code with Remote Development extensions for the backend.

Usage

Login

• First-Time Users: You will need a login code (authentication token) provided by an administrator.
• Login Screen: Enter your login code to access the app's features.

Home Screen

• Role Detection: The app detects your role (Participant, Coach, Admin) and displays relevant tabs.
• Tabs Available:
  • Participants
  • Coach (if applicable)
  • Admin (if applicable)
  • Theory
  • Links

Participants Tab

• View Upcoming Sessions: See a list of scheduled training sessions.
• Register Participation: Indicate your attendance status (Yes, No, Maybe).
• Add Users: Register on behalf of other users (e.g., family members).
• Session Details: Tap on a session to view more information.

Coach Tab

• Create Sessions: Add new training sessions with details like time, coach, and comments.
• Update Sessions: Modify or delete upcoming sessions.
• Register Attendance: Record actual attendance for sessions that are about to start or have ended.
• Participation History: Access historical data of participant attendance.

Admin Tab

• User Management: Create, update, or delete user accounts.
• View Authentication Tokens: Retrieve login codes for users.
• Role Assignment: Assign roles to users (Admin, Coach, Student).

Theory Tab

• Theory Training: Access taekwondo theory material categorized by belt levels.
• Quiz Modes:
  • Hidden Explanation: Test your knowledge by recalling explanations.
  • Training: Review terms and explanations together.
  • Hidden Term: Recall terms based on explanations.

Links Tab

• External Resources: Quick access to the club's website, Facebook group, and TikTok page.
• Documentation: Expandable sections with detailed guides for each tab.