npm install
npm run devif you are using other package manager instead of npm you need replace the npm command in the package.json
Importants files are
- src/config/index Handle environment variables
- src/controllers/orderbook.controller.ts controllers and endpoints
- src/http/orderbooks.http file to test requests
- src/services/orderbook.service.ts implementation of WS for bring realtime book data
- src/tests/ob.service.test.ts tests to check logic of orderbook.service
- src/tests/ob.test.ts tests to check controllers
Under src/http/orderbooks.http you'll find a request file in order to test the endpoints locally
Test uses a fake implementation of orderbook.services placed inside of src/tests/fake/orderbook.service.ts this dummy implementation always use the same book data placed in sampleData.ts in order to generate always the same expected result and check the logic for the different calculations.
I had a lot of problems with the checksum for Bitfinex WS, my internet connection is not totally reliable and many times the checksum failed after some seconds, I implemented some logic in order to reconnect the websocket if checksum fails and method response wait a few seconds if ws is connecting.
I created an environment variable that can be set in order to enable or disable checksum, in production this must be enabled, but locally you can omit this
WS_PAIRS = BTCUSD,ETHUSD