Live Data Client (LDC) is a client for the Wisebed Testbed, which displays sensor readings live in the web.
When a program is deployed on the testbed that periodically sends sensor readings, the LDC fetches these readings utilizing the Testbed Runtime's client utilies, publishes them on a channel using Redis's publish/subscribe mechanism.
To push the data to the browser a NodeJS server in conjunction with the Socket IO library is used. The NodeJS server uses a Redis client to subscribe to the sensor readings channel and pushes the incoming data to the browser with Socket IO websockets.
The browser client uses the Smoothie chart library to display the live data. A chart is drawn for every sensor node's incoming data stream.