Heart rate and respiratory monitoring

For this example, we're going to show data pushed from a backend server. Specifically, we're going to visualize heart rate and respiratory data which is pushed over a WebSocket to our D3 frontend.

We're going to recreate the following visualization (the DVD3/src/chapter-06/D06-02.html example):

To get this example up and running, we're going to take the following steps:

1. Get sample respiratory data which we can push to the frontend.
2. Create a simple WebSocket server, which pushes the information.
3. Make the D3 visualization which responds to information pushed from the server.

We start with the sample data.

Getting the sample data

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