Let's create a brand new package in a different project. Why a different project? We have explored the idea that the API deserves its own set of features and that we should decouple it from the core layer using a well-defined interface that we will mock. Since it is a different problem domain, we should create a different package. This way, we can develop them and manage their life cycles in an independent fashion.
Tip
For a simple project like this, it is OK if you prefer to simply put both layers in the same package.
So, let's create a mycafe-api/ folder with the same project layout we have been using so far. Initialize the project by creating a basic package.json file, and then, run the following commands to install the packages we need:
$ ~/mycafe-api> npm install --save-dev chai sinon sinon-chai chai-as-promised request mocha $ ~/mycafe-api> npm install --save express q
Note that I am installing express as a runtime dependency (version 4.x). This is...