crypto-calculator

This backend application calculates profitability for all crypto assets.

To Run db migrations:

knex migrate:latest

To Run db seeds:

knex seed:run

Seed data includes both purchase and trade information.

1. All purchases --> usd to crypto.
2. All trades --> crypto1 to crypto2.

Scripts

In the scripts directory are node files which perform specific operations related to calculating profitability. The field I need to calculate for each cryptocurrency is weighted_usd_per_unit.

Example 1. updatePrice.js

node scripts/updatePrice.js

To calculate profitability, I need the most current prices.

This script fetches the latest price information for 10 cryptocurrencies.

Prices are from CoinMarketCap

Fetched data will update entries in the coins_index table.

Example 2. updateBalancePurchases.js

node scripts/updateBalancePurchases.js

Because a single purchase contains less data, calculating weighted_usd_per_unit for purchases is much simpler.

For each purchased cryptocurrency, this script calculates:

1. the sum
2. the weighted_usd_per_unt

Then, the calculated objects are inserted into the balances table.

Calculating Profitability

To calculate weighted_cost_per_unit, run this script:

knex migrate:rollback && knex migrate:latest && knex seed:run && node scripts/updatePrice.js && node scripts/updateBalancePurchase.js && node scripts/weightedCost

After these six commands, in the balances table is an updated entry for each cryptocurrency.

In the balances table. Each unique cryptocurrency should show the sum of all liquid units (how much of this currency I have available) and the weighted_usd_per_unit.

if coins_index.usd_per_unit > balances.weighted_usd_per_unit, then that cryptocurrency is PROFITABLE!

ERD: