node-red-contrib-services-mentor/services/mysql-db.js

Mentor Services

module.exports = function(RED) {
    var mysql = require('mysql');
    var reconnect = RED.settings.mysqlReconnectTime || 20000;
    var log = RED.log;
  
    function MySQLNode(n) {
        RED.nodes.createNode(this,n);
        this.host = n.host;
        this.port = n.port;
        this.tz = n.tz || "local";

        this.connected = false;
        this.connecting = false;

        this.dbname = n.db;
        this.setMaxListeners(0);
        var node = this;

        function checkVer() {
            node.connection.query("SELECT version();", [], function(err, rows) {
                if (err) {
                    node.connection.release();
                    node.error(err);
                    node.status({fill:"red",shape:"ring",text:"Bad Ping"});
                    doConnect();
                }
            });
        }

        function doConnect() {
            node.connecting = true;
            node.emit("state","connecting");
            if (!node.pool) {
                node.pool = mysql.createPool({
                    host : node.host,
                    port : node.port,
                    user : node.credentials.user,
                    password : node.credentials.password,
                    database : node.dbname,
                    timezone : node.tz,
                    insecureAuth: true,
                    multipleStatements: true,
                    connectionLimit: 25
                });
            }

            node.pool.getConnection(function(err, connection) {
                node.connecting = false;
                if (err) {
                    node.emit("state",err.code);
                    node.error(err);
                    node.tick = setTimeout(doConnect, reconnect);
                }
                else {
                    node.connection = connection;
                    node.connected = true;
                    node.emit("state","connected");
                    node.connection.on('error', function(err) {
                        node.connected = false;
                        node.connection.release();
                        node.emit("state",err.code);
                        if (err.code === 'PROTOCOL_CONNECTION_LOST') {
                            doConnect(); // silently reconnect...
                        }
                        else if (err.code === 'ECONNRESET') {
                            doConnect(); // silently reconnect...
                        }
                        else {
                            node.error(err);
                            doConnect();
                        }
                    });
                    if (!node.check) { node.check = setInterval(checkVer, 290000); }
                }
            });
        }

        this.connect = function() {
            if (!this.connected && !this.connecting) {
                doConnect();
            }
        }

        this.on('close', function (done) {
            if (this.tick) { clearTimeout(this.tick); }
            if (this.check) { clearInterval(this.check); }
            node.connected = false;
            node.emit("state"," ");
            node.pool.end(function (err) { done(); });
        });
    }
    RED.nodes.registerType("MySQLdb",MySQLNode, {
        credentials: {
            user: {type: "text"},
            password: {type: "password"}
        }
    });

}