Fantasy Football Assistant Manager Backend

Contributors: Eric, Noah, Temi, Zac

Table of Contents

• Project Overview
• Project Purpose
• Features
• Tech Stack
• Setup & Installation
• API Endpoints
• Testing

Project Overview

FFOracle is a comprehensive fantasy football assistant manager application that helps users make data-driven decisions for their fantasy football leagues. The backend provides a robust RESTful API that powers AI-driven roster recommendations, player comparisons, league performance tracking, and secure payment processing.

• Frontend Repository:https://github.com/EricNohara/Fantasy-Football-Assistant-Manager-Frontend
• Updater Repositoryhttps://github.com/EricNohara/FFOracle-Updater/
• Production: Deployed on Azure App Service

Features

• Real-Time NFL Data - Integration with NFLVerse and ESPN APIs for current player statistics
• Automated Updates - Weekly updates for player stats, team data, game schedules, and betting odds
• Comprehensive Stats - Season stats, weekly stats, defensive stats, betting lines, and injury reports
• AI-driven Roster Recommendations - Get personalized start/sit recommendations for entire rosters based on player stats, matchups, betting lines, and custom scoring settings
• Player Comparison Tool - Compare any two players with detailed AI analysis and recommendations
• League Performance Tracking - Track weekly performance, accuracy metrics, and roster optimization across multiple weeks

Tech Stack

• Backend Framework: ASP.NET Core Web API (.NET 8)
• Database: Supabase (PostgreSQL)
• Authentication: Supabase JWT Authentication
• Language: C#
• Version Control: Git

Setup & Installation

The backed and frontend code can be downloaded from this repository and
https://github.com/EricNohara/Fantasy-Football-Assistant-Manager-Frontend
respectively. On downloading, navigate to each solution directory from the command line and enter "dotnet restore" to install all necessary packages. Obtain your own API keys and accounts for Supabase, NFLVerse, OpenAI, and Stripe. Create the file "appsettings.json" with body:

{
//supabase keys
"Supabase": {
"Url": ,
"ServiceRoleKey":
},
//stripe keys
"Stripe": {
"PublishableKey": ,
"SecretKey": ,
"WebhookSecret":
},
"OpenAI": {
"ApiKey":
},
"Logging": {
"LogLevel": {
"Default": "Information",
"Microsoft.AspNetCore": "Warning"
}
},
//Indicates hosts from which requests can be accepted. Currently set to accept all.
"AllowedHosts": "*"
"Smtp": {
"Host": ,
"Port": ,
"Username": ,
"Password": ,
"UseSSL": ,
"UseStartTls": ,
"SenderName": ,
"SenderEmail": }
}

Fill in all empty fields with your API keys. In order to test Stripe webhooks, you will have to download the Stripe CLI. More information can be found here: https://docs.stripe.com/stripe-cli
After downloading, open the command line and run "stripe login". Follow the instructions that appear to link this machine to your Stripe account.

Api Endpoints

Authentication & User Management

Method	Endpoint	Description	Auth Required
POST	/api/Users/signup	Register a new user	No
POST	/api/Users/login	Authenticate and receive JWT token	No
POST	/api/Users/request-password-reset	Request password reset email	No
POST	/api/Users/reset-password	Reset password with token	No
PUT	/api/Users	Update user information	Yes
DELETE	/api/Users	Delete user account	Yes

AI-Powered Features

Method	Endpoint	Description	Auth Required	Tokens Cost
GET	/api/RosterPrediction?leagueId={id}	Get AI roster recommendations	Yes	10 tokens
GET	/api/PlayerComparison/{id1}/{id2}/{position}?leagueId={id}	Compare two players	Yes	1 token

League Management

Method	Endpoint	Description	Auth Required
POST	/api/GetUserData/create-league	Create a new fantasy league	Yes
GET	/api/GetUserData/user-leagues	Get all leagues for authenticated user	Yes
GET	/api/GetUserData/league/{id}	Get detailed league information	Yes
PUT	/api/UpdateUserLeague/roster-settings	Update league roster settings	Yes
PUT	/api/UpdateUserLeague/scoring-settings	Update league scoring settings	Yes
POST	/api/UpdateUserLeague/add-member	Add player/defense to league roster	Yes
DELETE	/api/UpdateUserLeague/remove-member	Remove player/defense from roster	Yes
PUT	/api/UpdateUserLeague/update-picks	Update start/sit picks for players	Yes

League Performance

Method	Endpoint	Description	Auth Required
GET	/api/LeaguePerformance/{leagueId}/week/{week}	Get league performance metrics	Yes

NFL Data

Method	Endpoint	Description	Auth Required
GET	/api/GetPlayersByPosition?position={pos}	Get players by position (QB, RB, WR, TE, K)	Yes
GET	/api/ESPN/news/nfl	Get NFL news from ESPN	No
GET	/api/ESPN/news/nfl/{playerId}	Get news for specific player	No

Payments

Method	Endpoint	Description	Auth Required
POST	/api/Stripe/create-payment-intent	Create Stripe payment intent	No
POST	/api/StripeWebhook/check-payment-completion	Webhook for payment events	No (Stripe signature)

Internal/Admin (Auto-Update)

Method	Endpoint	Description
POST	/api/AutoUpdate/all	Run all weekly data updates
POST	/api/Players/all	Update all NFL player data
POST	/api/Team/all	Update all NFL team data
POST	/api/GamesThisWeek/all	Update weekly game schedule

Testing

The app has been deployed to the link https://fforacle.vercel.app. Testing of the features can be done so there.

If looking to test the app locally:

Most features of this test implementation can be tested using the auto-generated Swagger UI.

To start the backend:

dotnet run --launch-profile "https"

Once running, copy the local URL displayed in the console and open it in your browser — then append /swagger to the end.

https://localhost:5001/swagger

This will open the Swagger testing interface.

---

Supabase Testing

1. In Swagger, select the Supabase endpoint.
2. Click "Try it out".
3. In the table field, enter the name of any table in the project database schema (e.g., "Users").
4. Click "Execute".

This will retrieve all entries from the given table.

Note: The Supabase database is not yet fully populated.

---

ChatGPT Testing

1. Select the ChatGPT Test endpoint.
2. Click "Try it out".
3. Enter a quotation-enclosed string (e.g., "Hello ChatGPT!").
4. Click "Execute".

Sample Query:

{
"message": "Return a json object with fields whoToStart and reasoning: {\"player_one\": {\"name\": \"Aaron Rodgers\", \"position\": \"QB\", \"team\": \"PIT\", \"completions\": 74, \"attempts\": 108, \"passing_yards\": 786, \"passing_tds\": 8, \"passing_interceptions\": 3, \"sacks_against\": 9, \"passing_air_yards\": 515, \"passing_first_downs\": 31, \"passing_epa\": 6.51129352118511, \"carries\": 9, \"rushing_yards\": 11, \"rushing_tds\": 0, \"fumbles\": 1, \"rushing_first_downs\": 1, \"rushing_epa\": -2.51797030409565, \"fantasy_points\": 60.54, \"fantasy_points_ppr\": 60.54}, \"player_two\": {\"name\": \"Daniel Jones\", \"position\": \"QB\", \"team\": \"IND\", \"completions\": 87, \"attempts\": 121, \"passing_yards\": 1078, \"passing_tds\": 4, \"passing_interceptions\": 2, \"sacks_against\": 4, \"passing_air_yards\": 1013, \"passing_first_downs\": 52, \"passing_epa\": 38.9130099857412, \"carries\": 18, \"rushing_yards\": 54, \"rushing_tds\": 3, \"fumbles\": 1, \"rushing_first_downs\": 8, \"rushing_epa\": 8.26075707325101, \"fantasy_points\": 78.52, \"fantasy_points_ppr\": 78.52}}"
}

The response will display ChatGPT’s reply to your input string.

---

NFLVerse Testing

1. Select the Players (POST) endpoint.
2. Click "Try it out", then "Execute".
3. This retrieves all NFL player data from NFLVerse and stores it in the project Supabase database.
4. To confirm, use the Supabase testing steps above and enter the table name "Players".

---

Stripe Testing

To view Stripe event logs, stop the backend and set the environment to Development:

set ASPNETCORE_ENVIRONMENT=Development

This enables debug logs on the console.

Note: Stripe testing requires both the backend and frontend to be running.

1. Start the Stripe listener

Open a terminal and enter:

stripe listen --forward-to https://localhost:<local port>/api/stripewebhook/check-payment-completion

This will register your machine as a temporary webhook endpoint.

2. Test the payment flow

From the frontend UI, enter the following test card info:

Number	Expiration Date	CVC
4111 1111 1111 1111	any future month/year	111

This is a fake credit card for testing only.

Press "Pay $10" to initiate a payment.
You should see a PaymentIntent succeeded log in your backend console.
Your Stripe dashboard should show a successful $10 test payment.