node-red-contrib-socketcan/src/receive.js

node-red nodes for socketcan

///////////////////////////////////////////////////////////////////////////
// receive.js
//
// socketcan input node.
//
// This file is part of the VSCP (https://www.vscp.org)
//
// The MIT License (MIT)
//
// Copyright © 2020-2024 Ake Hedman, Grodans Paradis AB
// <info@grodansparadis.com>
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//

module.exports = function(RED) {

	"use strict";
	
	// Debug:
	// https://nodejs.org/api/util.html
	// export NODE_DEBUG=socketcan-out  for all debug events
	const util = require('util');
	const debuglog = util.debuglog('socketcan-out');
	
    var can = require('socketcan');

    function SocketcanReceiveNode(config) {

		RED.nodes.createNode(this,config);
		
		this.config = RED.nodes.getNode(config.config);

		if(this.config) {
			this.interface = this.config.interface;
		}
		else {
			return;	// Do nothing
			//this.interface="vcan0";
		}

		debuglog("CAN interface = " + this.interface);

		var node = this;

		// Tell the world that we are connecting to the interface
		this.status({fill:"yellow",shape:"dot",text:"connecting... " + "<" + this.interface + ">"});

		var sock;
		try {
			// Create raw interface with timestamp
			sock = can.createRawChannel("" + this.interface, {
				timestamps: true
			});
		} catch(err) { 
			// Did not handle this interface
			node.error("Error: " + err.message + this.interface);
			this.status({fill:"red",shape:"dot",text: err.message + "<" + this.interface + ">" });
		}
		if (sock) {

			// Start things up
			sock.start();

			// Tell the world we are on
			this.status({fill:"green",shape:"dot",text:"connected " + "<" + this.interface + ">" });
		
			// Add a message listener
			sock.addListener("onMessage",function(frame) {
				debuglog("CAN message :",frame);
				var msg={};
				msg.payload = {};
				msg.payload.timestamp = frame.timestamp || new Date().getTime();
				msg.payload.ext       = frame.ext || false;
				msg.payload.canid     = frame.id; 
				msg.payload.dlc       = frame.data.length;
				msg.payload.rtr       = frame.rtr || false;
				msg.payload.data = [];
				//msg.payload.data.push(frame.data);
					
				msg.payload.data =  Array.prototype.slice.call(frame.data, 0);
        msg.payload.rawData = frame.data;
				node.send(msg);
			});
			
			///////////////////////////////////////////////////////////////////
			//                          on close	
			///////////////////////////////////////////////////////////////////
			this.on("close", function(removed, done) {
				
				sock.stop();
				
				// Tell the worl we had gone down
				this.status({fill:"red",shape:"dot",text:"disconnected."});

				if (removed) {
					// This node has been deleted
				} else {
					// This node is being restarted
				}
			
				done();
			});	
		}
    }
    RED.nodes.registerType("socketcan-out",SocketcanReceiveNode);
}