Stock Data Downloader - Python Flask App

This Python Flask web application allows users to download historical stock data in Excel format using the Yahoo Finance API (yfinance). The user simply enters a stock ticker symbol and selects a date range, and the app fetches the stock data for that range, converting it into an Excel file ready for download.

Features

• Stock Data Download: Allows users to enter a stock ticker, a start date, and an end date to retrieve historical stock data.
• Excel Export: The stock data is exported in an Excel format for easy offline analysis.
• User-Friendly Interface: Simple web interface for entering the stock ticker and date range.

Prerequisites

Before running the application, ensure that you have the following installed:

• Python 3.x
• Flask
• yfinance
• pandas
• openpyxl

To install the required dependencies, run:

pip install flask yfinance pandas openpyxl

Application Structure

The project consists of two main components:

1. Flask App (Python): This file contains the logic to handle user input, fetch stock data, and generate the Excel file.
2. HTML Template (index.html): This is the front-end form where users can input stock tickers and select date ranges.

Directory Structure

stock-data-downloader/
│
├── app.py           # Python Flask application file
├── templates/
│   └── index.html   # HTML template for the user interface
└── requirements.txt # List of dependencies

Running the Application

1. Clone or download the repository.
2. Navigate to the project directory.
3. Run the Flask application using the following command:

python app.py

4. Open your web browser and go to http://127.0.0.1:5000/.
5. Enter a stock ticker, start date, and end date, then click Download Data to get the stock data in Excel format.

Code Explanation

Flask App (app.py)

• Imports:

  • Flask, render_template, request, and send_file from flask handle web server functionality.
  • yfinance fetches stock data from Yahoo Finance.
  • pandas is used to convert the data into an Excel file format.
  • BytesIO is used to handle the in-memory byte stream for sending the file.

• Routes:

  • /: The homepage where the user can input the stock ticker and date range.
  • /download: A POST route that handles the data download by fetching the stock data and converting it into an Excel file.

• Logic:

  • The download route processes the form input (stock ticker, start date, and end date).
  • It fetches the stock data using yfinance and checks if the data is empty.
  • If data is available, it is converted into an Excel file using pandas.ExcelWriter.
  • The file is then sent to the user as a downloadable Excel file.

HTML Template (templates/index.html)

The HTML template provides a simple form with the following inputs:

• Stock Ticker: A text input for the user to enter the stock symbol (e.g., "AAPL").
• Start Date: A date input for selecting the start date.
• End Date: A date input for selecting the end date.

When the form is submitted, the data is sent to the /download route in a POST request.

Created by:

• Muntaqim Asbuch
• GitHub: @shemilael
• Instagram: @shemilael

License

This project is licensed under the MIT License - see the LICENSE file for details.