@node-red/flow-parser

@node-red/flow-parser

This module provides a set of utilities for working with Node-RED flows.

Usage

const fs = require("fs");
const { parseFlow } = require("@node-red/flow-parser");

// Load the flow json from a local file and parse to an object
const exampleFlow = JSON.parse(fs.readFileSync("flows.json", "utf-8"));

// Parse the flow
const flow = parseFlow(exampleFlow);

// `flow` is now an object that can be used to explore the flow structure

Example - walk

The walk function can be used to invoke a function on every object in the flow configuration in a reasonably well-defined order:

• Subflow definitions
  • Config nodes scoped to this subflow
  • Groups
  • Nodes
• Global Config nodes
• Flows
  • Config nodes scoped to this flow
  • Groups
  • Nodes

const fs = require("fs");
const FlowParser = require("@node-red/flow-parser");

// Load the flow json from a local file and parse to an object
const exampleFlow = JSON.parse(fs.readFileSync("flows.json", "utf-8"));

const flow = FlowParser.parseFlow(exampleFlow);

flow.walk(function(obj) {
    switch(obj.TYPE) {
        case FlowParser.types.Flow:
            // A flow object
            break;
        case FlowParser.types.Subflow:
            // A subflow definition
            break;
        case FlowParser.types.Group:
            // A group object
            break;
        case FlowParser.types.ConfigNode:
            // A config node
            break;
        case FlowParser.types.Node:
            // A flow node
            break;
    }
})

Example - export

The export function gives back the JSON array for the flow.

The following example will disable all Debug nodes in the flow:

const flow = parseFlow(exampleFlow);

flow.walk(obj => {
    if (obj.type === 'debug') {
        obj.active = false;
    }
});

const newFlow = flow.export();