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Payload Parser

Payload Parser allows you to manipulate the raw payload sent by devices. For example, it can be used to transform a HEX payload sent by a device into temperature and battery variables.

Associating it​

Payload Parsers must be associated to a Device, and you can define one by selecting a file in the Payload parser field of a Device. Each device can only have one Payload Parser.

Writing code​

info

Payload Parsers can only be written in JavaScript.

Inside of your JavaScript code, you can use the payload global variable to have access to the data sent by your device. You may also modify this global variable if you wish to change the data before it is saved in the Device's Bucket.

The global payload will contain whatever your Device has sent in the body of the HTTP request, which means it doesn't have a specific type and can be an array, object, or even a string or number.

Good to know
  • Your code doesn't need to be in a function;
  • You do not need to use a return statement at the end of your code;
  • You cannot use require, import, or window inside of your code.

In general, your script should not take too long to transform the payload of your Device in order to avoid a bottleneck in your application.

Code sample​

This code sample shows how you can convert a Celsius temperature value to a Fahrenheit temperature value.

// This code:
// 1. Finds the temperature inside the payload sent by the device;
// 2. Converts the value from Fahrenheit to Celsius;
// 3. Adds the unit.

// To test this code, make sure your device sends a POST request
// with a variable named "temperature".

// First, we find the temperature variable inside the payload (array)
const temperatureItem = payload.find((i) => i.variable === 'temperature');

if (temperatureItem) {
  // If we find the variable, we convert the value

  const actualTemperatureInFahrenheit = temperatureItem.value;
  const celsius = (5 / 9) * (actualTemperatureInFahrenheit - 32);

  // Set the value and unit
  temperatureItem.value = celsius;
  temperatureItem.unit = 'C';
}