Getting started:

• Run the circle postgres SQL DB docker image as noted in the questionnaire.
• Install Node and NPM. Since I use ES6, you'll need Node version > 5.
  • I recommend using brew to install Node on Mac OSX. If you wish to use multiple versions of Node, use n
• Install sequelize globally:

   npm install -g sequelize-cli

• Install NPM dependencies:

   cd <folder-name>
   npm install

• Initialize database schema:

   cd server
   sequelize db:migrate

• Seed the database:

   sequelize --url postgres://circle:circle@localhost:5432/circle db:seed:all

• Run the server:
  • Development mode:

     npm run start:dev

  • Production mode:

     export NODE_ENV="production"
     node bin/www

Note: The server runs on port 8000 by default. To change it, set the environment variable PORT to something else.

APIs:

• Accounts

  • POST /api/accounts - Create a new account. req.body should be JSON with the following attributes: userid (string) and balance (int)
  • GET /api/accounts - Get all accounts
  • GET /api/accounts/ - Get a particular account's details
  • PUT /api/accounts/ - Update the balance of a particular account. req.body should be JSON with the following attribute: balance (int)

• Transactions

  • POST /api/transactions - Create a transaction. Does verifications and commits only if all operations are successful. req.body should be JSON with the following attributes: from_user (string), to_user (string), amount (int). These are self-explanatory.
  • GET /api/transactions - Get all transfers that were made in the system. Also an alias to api/transfers
  • GET /api/transactions/ - Get a particular transfer. Also an alias to api/transfers/

Suggested improvements:

• Add seed information for initializing database
• Enhance transfers to save operation status and details
• Running queries concurrently in transactions
• Write automated tests

(c) Kiran Kashalkar