Propine Blockchain Engineer Assignment

We're looking at your programming ability. It must not only work, it should be maintainable.

Let us assume you are a crypto investor. You have made transactions over a period of time which is logged in a CSV file. Write a command line program that does the following

• Given no parameters, return the latest portfolio value per token in USD
• Given a token, return the latest portfolio value for that token in USD
• Given a date, return the portfolio value per token in USD on that date
• Given a date and a token, return the portfolio value of that token in USD on that date

The CSV file has the following columns

• timestamp: Integer number of seconds since the Epoch
• transaction_type: Either a DEPOSIT or a WITHDRAWAL
• token: The token symbol
• amount: The amount transacted

Portfolio means the balance of the token where you need to add deposits and subtract withdrawals. You may obtain the exchange rates from cryptocompare where the API is free. You should write it in Node.js as our main stack is in Javascript/Typescript and we need to assess your proficiency.

• Change .default.env to .env and check environment variables

• Install all missing package by run this command blow in terminal

yarn

• At the project's root, in terminal run application by

node .

• For unit test run by

yarn test

├── LICENSE
├── main.js
├── package.json
├── README.md
├── src
│  ├── api
│  │   └── currency.js
│  ├── constants
│  │   └── constants.js
│  ├── services
│  │   ├── parse-content.js
│  │   ├── read-file.js
│  │   └── transaction.js
│  └── utils
│      ├── color.js
│      ├── menu.js
│      └── time-convert.js
├── test
│   ├── init-chai.js
│   ├── mocks
│      └── transactions-100.csv
│   ├── transaction.test.js
│   └── time-convert.test.js
└── .default.env

• Speed up processing large data from parse file to get some object transformation

  • Apply thread, child process while processing data
  • Snapshot while reading (by time range) => using redis cached and from now, read from cache

• Update unit test to cover all functions and missing case