GDAX API PLAYTHROUGH

Description

This API contains one endpoint /quote allowing to get a quote for any currency pair supported by the GDAX API.

Trade-offs

• Getting the currency pairs as an hardcoded string array in the quote.js file directly to prevent having them pulled from the API at every request. Seemed appropriate as the documentation states that if a pair/id exists it will not be removed. They could also be loaded from a configuration file but hardcoding allows to keep this implementation simpler.

Improvements to add

• More descriptive error messages in terms of what input to correct, etc.
• Return an error message in case there is no order small/big enough to satisfy the quote.
• Add unit tests for cases where the best priced orders have a quantity too big for the quote.
• Add unit tests for reversed quotes handling (i.e. BTC-ETH)

UNIX setup

• You will need Node.js and NPM setup on your system.
• Once you have these setup you can load the project dependencies by running npm install in this directory.
• Once the dependencies installed, you can usenpm start to run the API. This will start the Express server on the port 8888. However if a PORT environment variable is setup it is going to be used as port to serve the API.
• You can also run unit tests using npm test.