JavaScript Processor

2 min

This processor function enables users to use JavaScript as a programming language for manipulating and managing data coming from input tags.

Define your script in the Code Editor. The editor is a user-friendly interface for writing and editing JavaScript, supporting syntax highlighting and real-time validation. Write the JavaScript code you want to execute. Learn more here.

At the right you can access:

Playground Test, write, and validate processors in real-time before deploying them.

Validate Validate your code.

Note: When creating an analytics flow with JavaScript Processor processor, refer the Use the JavaScript Processor Function guide for more details.

JavaScript Overview

This processor uses JavaScript scripting

Simple Use case: The output you receive from DeviceHub message or from Analytics, might not be helpful, and you want to change the name of a field within that message

In general, if you want to add, remove or modify ANY field in the input, this scripting processor is very useful. For example:

Instead of "value" you want your data to show "furnace pressure"

Instead of having all fields of the message, you only want to have "success", "deviceId" and "value" and skip everything else

You want to add a custom field to the message, based on the "value" field, such as: if value = 2, "error": "overheating"

You only want to change the timestamp to human readable format instead of Unix timestamp, but keep otherwise keep the message as-it-is

Single Input: Every message from the input, is stored as an array called "values"

Using "for i, message in values{}" statement, allows to access this input and manipulate it

Here "i" represents what is the definition defined in the connection wire, more useful for multi-inputs, to identify and distinguish between each inputs, so for single input, "i" can be replaced with "_"

"message" contains the entire message in the input, and you can perform your manipulations to this "message" parameter

Note: "i" and "message" can be any custom variable name

Multiple Input: Suppose you have 3 different inputs attached to this scripting processor, with the connecting wires named A, B and C

"for i, message in values{}" will now have 3 inputs

"i" represents from which connection wire is the input coming from

with if-else statements, every input can be manipulated in isolation, or a common manipulation can be applied to all inputs

You can choose to output "result" only for one input, or all of the inputs