nrlint - Node-RED Flow Linter

nrlint is a linting tool for identifying potential problems with Node-RED flows.

It can be used within the Node-RED editor or run as a command-line tool.

Installation and Usage

In the editor

In your Node-RED user directory (typically ~/.node-red), run:

npm install nrlint

You can then generate a default configuration file with:

npx nrlint --init > .nrlintrc.js

Edit your Node-RED settings file, ~/.node-red/settings.js and add the follow inside the module.exports block. Remember, each entry in the block must be separated by a comma (,).

module.exports {
    // Add a `nrlint` entry pointing to your nrlint config file
    nrlint: require("./.nrlintrc.js"),
}

Finally, restart Node-RED.

In the editor you will now have a linter sidebar available. It will report any warnings or errors the linter detects whilst you edit your flows.

The cog icon at the top of the sidebar allows you to customise your linter configuration. Note that doing so will not modify the .nrlintrc.js file you created - the new configuration will be stored in the editor preferences.

Command-line usage

You can run nrlint as a command line tool to lint a local json flow file.

Following the instructions above to install nrlint. You can then run it from the ~/.node-red directory using npx:

npx nrlint myFlowFile.json

Run with --help to see the available options.

Developing

To use the development version of nrlint you can clone its source code repository and build it yourself.

1. Get the source code

git clone https://github.com/node-red/nrlint.git

2. Install the dependencies

cd nrlint
npm install

3. Build the plugin

npm run build

4. Install into Node-RED

cd ~/.node-red
npm install <path-to-nrlint-directory>

5. Restart Node-RED to load the linter.

Source code structure

• bin - CLI executable
• lib - main source code of the linter
  • cli - source code of the CLI
    • formatters - source code of the output formatters used by the CLI version
  • rules - source code of the built-in rules
    • function-eslint - source code of the built-in function-eslint rule.
• scripts - build scripts used by npm run build
• src - source code of the plugins

After npm run build is run, the following directories will be created:

• dist - contains the built plugin files
• resources contains the built Worker files

## Acknowledgements

nrlint is modelled after eslint and borrows many of its concepts.