Just as an orchestra needs a conductor, Internet of Things (IoT) devices and web services need a tool that wires them together, defines their roles, and specifies rules for their behavior. This is essentially what Node-RED [1] does. Built by IBM, this open source Node.js-based application provides a graphical environment for building flows – simple and complex programs that tie various devices and services together, as well as manipulate and move data between them.

This functionality makes it possible to automate various tasks and program devices and services by connecting Node-RED modules called nodes and adding a dash of JavaScript code. For example, you can easily create a simple flow that pulls and processes weather data from the OpenWeatherMap service and sends daily weather reports to a specified email address. It is also possible to set up a flow that reads data from sensors connected to a Raspberry Pi or Particle's Photon WiFi board and pushes the obtained data to a Google Docs spreadsheet or Twitter. To automate tasks and orchestrate IoT devices and services, you need to master Node-RED's basics, and in this article, I will help you to get started with this powerful and versatile application.

Installing Node-RED

Although Node-RED can run on a regular Linux computer, you might want to use a dedicated machine to act as a Node-RED server (see the "Using FRED" box for more options); a low-cost single-board computer like Raspberry Pi is perfect for that. In fact, the latest version of Raspbian based on Debian Jessie has Node-RED preinstalled, so you don't even need to spend time deploying the application.

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