This article walks through how I created and published my Node-RED module “node-red-contrib-flatter” to NPM. Using the flat NPM package, it consists of two nodes to flatten and unflatten JavaScript objects.

https://www.npmjs.com/package/node-red-contrib-flatter

https://github.com/SenorGrande/node-red-contrib-flatter

Starting the node

Following the Node RED documentation to create a node that converts msg.payload to lowercase, I was able to create the foundation of my package.

https://nodered.org/docs/creating-nodes/first-node

The main differences from the starter node:

In the Node-RED documentation, you create a lower-case.js file. For my package, I created a flatter.js & unflatter.js file, one for each node. I needed to require the “flat” NPM package, so I saved this as a dependency: npm i --save flat

I can now require this in my flatter.js and unflatter.js files: var flatten = require('flat'); var unflatten = require('flat');

And instead of this line in the example lower-case.js file: msg.payload = msg.payload.toLowerCase(); I replaced it with: msg.payload = flatten(msg.payload); in flatter.js, and
msg.payload = unflatten(msg.payload); in unflatter.js

Unit tests

Following the Node-RED documentation, I created a folder called “test” with a flatter_spec.js file. I only added a simple test for flattening and unflattening a payload and then checking the output matches the expected output.

Below are the dependencies I saved to my package for developing, mocha and node-red-node-test-helper. Dependencies saved to “devDependencies” with --save-dev aren’t installed when someone installs your package from NPM.
npm i --save-dev mocha node-red node-red-node-test-helper

Package.json

Add “node-red” as a keyword to package.json when you are ready and it should show up on the Node-RED library flows.nodered.org within a few hours. It can then be searched in the Node-RED palette manager. Only do this when your package is ready! Also, add other keywords that relate to your package so that it can be searched for on NPM.

"keywords": [
  "node-red"
],

Add your nodes:

"node-red": {    
  "nodes": {      
    "flat": "flatter.js",
    "unflat": "unflatter.js"
  }
},

Add a test command under scripts:

"scripts": {
  "test": "mocha \"test/**/*_spec.js\""
},

To run your unit tests, try npm test in the console.

GitHub Actions

There are already many templates to choose from. I added the node.js test (which runs on every push) and node.js package actions (which runs on every release created). Personally, I removed the part that publishes to GitHub Packages.

Create an account with NPM at https://www.npmjs.com/. Create a token under “Auth Tokens” with type “Publish”, add it as a secret to your repo with the name “npm_token”, stick it in the GitHub action as an environment variable NODE_AUTH_TOKEN:${{secrets.npm_token}} This should already be in the node.js package template. Create a release in GitHub, (click on “releases” in the top bar and then “Draft a new release”) voila, the GitHub Action will check that it passes the uni tests and then publish the package to NPM.

Hope this helped you out! Chur.