2.4. Exploring the Hello World Snap

2.4.1. Overview

The Hello World snap is a simple Node.js application for communications with the Nordic Thingy:52.

The application is a daemon which discovers the Thingy, connects to it and after that transceives the data from the sensors to an MQTT Broker.

You can use the Rigado Playground to get access to this data.

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Figure 2.1 Data Flow

2.4.2. Installing rigado-node-hello-world

Install the rigado-node-hello-world app (stable channel) to the default bundle. Follow the guide in Removing an App for instructions on how to do this.

2.4.3. Connecting a Thingy

Once the gateway has the rigado-node-hello-world app, it will be listening for any active Thingy and trying to connect to it.

Turn on the Thingy

The power switch for the Thingy is located under the rubber enclosure, next to the USB charging port.

The Thingy has an LED to display information. When the Thingy is turned on but before it has connected to anything, the LED will blink blue. After the Thingy has connected to the gateway the LED will blink green.

Note

If the Thingy does not detect movement for a long time it goes into a sleep state and will wake up when movement is detected (e.g. shaking).

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Figure 2.2 A free Thingy

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Figure 2.3 A connected Thingy

2.4.4. Browse the Dashboard

Once the Thingy has connected, navigate your browser to https://playground.rigado.com/dashboards/node-hello-world

Do not modify the Subscription URL field.

Change the Subscription topic field to /gateway/GATEWAY_SERIAL/sensors where GATEWAY_SERIAL is the serial number found on the sticker on the bottom of the gateway.

Note

This field is case-sensitive, so be sure to input the gateway serial number exactly as it’s printed on the gateway.

After that click on the Subscribe to topic button.

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Figure 2.4 Change Settings

You will get actual data from the Thingy every few seconds.

To see the changes in the Accelerometer data you can shake the Thingy.

To set the marker on the time-series chart, push the button on the Thingy.

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Figure 2.5 Thingy Data

2.4.5. Next Steps

To learn how to build the hello-world snap and front-end web application for yourself, see our tutorial series: