Stock Comparison

This is a simple React application built around the AlphaVantage API to query and select up to 3 stocks to compare. It shows the stock's daily price data and anual earnings per share. Built with React, MobX, and Typescript. Tests with Jest.

Prerequisites

You need an AlphaVantage API key to run this application. Get one here:

https://www.alphavantage.co/support/#api-key

Installation

1. Copy your AlphaVantage API key and paste it into the .env file.
2. Run yarn && yarn start to install dependencies and start the development server. Access the application at http://localhost:3000.

Tests

Jest tests for some of the components, API methods, and stores are provided.

yarn test

Known Issues

• The AlphaVantage free API is limited to 5 calls per minute and 500 per day. In practice, this results in the application being unable to lookup a selected stock (the queries for searching for a stock seem unaffected by the API limit, though). When this happens, the selected stock card will display with an error and Retry button to refetch the stock data. Just wait a minute and try again.