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sql-servernode.jsrestnode-mysql

Getting Error "Error: Cannot enqueue Handshake" Using node-mysql For MS SQL Server and node App Connectivity?


I have developed a REST api using node.js. My api is running on my macbook. I am trying to access MS SQL server running on another machine using node-mysql module, but while trying to create a connection I am getting the following error:

GET /contacts/ 200 12.467 ms - - events.js:141 throw er; // Unhandled 'error' event ^

Error: Cannot enqueue Handshake after invoking quit. at Protocol._validateEnqueue (/Users/abc/Desktop/NodeProjects/MyWebsite/node_modules/mysql/lib/protocol/Protocol.js:202:16) at Protocol._enqueue (/Users/abc/Desktop/NodeProjects/MyWebsite/node_modules/mysql/lib/protocol/Protocol.js:135:13) at Protocol.handshake (/Users/abc/Desktop/NodeProjects/MyWebsite/node_modules/mysql/lib/protocol/Protocol.js:52:41) at Connection.connect (/Users/abc/Desktop/NodeProjects/MyWebsite/node_modules/mysql/lib/Connection.js:123:18) at read_json_file (/Users/abc/Desktop/NodeProjects/MyWebsite/models/contacts.js:15:14) at Object.exports.list (/Users/abc/Desktop/NodeProjects/MyWebsite/models/contacts.js:29:22) at /Users/abc/Desktop/NodeProjects/MyWebsite/app.js:38:44 at Layer.handle [as handle_request] (/Users/abc/Desktop/NodeProjects/MyWebsite/node_modules/express/lib/router/layer.js:95:5) at next (/Users/abc/Desktop/NodeProjects/MyWebsite/node_modules/express/lib/router/route.js:131:13) at Route.dispatch (/Users/abc/Desktop/NodeProjects/MyWebsite/node_modules/express/lib/router/route.js:112:3).

I have no Clue what this is saying, Can some one guide me through this?

The code of my two scripts is given below for understanding the problem? I am trying to connect to the MS Sql server through contacts.js scripts's "function read_json_file()" function.

App.js script code:

  var express        = require('express');
  var http           = require('http');
  var path           = require('path');
  var favicon        = require('serve-favicon');
  var logger         = require('morgan');
  var cookieParser   = require('cookie-parser');
  var bodyParser     = require('body-parser');
  var nodemailer     = require('nodemailer');
  var url            = require('url');

  var routes         = require('./routes/index');
  var contacts       = require('./models/contacts');

  var app            = express();

  // view engine setup
  app.set('views', path.join(__dirname, 'views'));
  app.set('view engine', 'jade');
  app.set('port', process.env.PORT || 3000);

  // uncomment after placing your favicon in /public
  //app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
  app.use(logger('dev'));
  app.use(bodyParser.json());
  app.use(bodyParser.urlencoded({ extended: false }));
  app.use(cookieParser());
  app.use(express.static(path.join(__dirname, 'public')));
  app.use('/', routes);
  //app.use('/contacts', contacts);

  // catch 404 and forward to error handler

  app.get('/contacts',function(request, response){
    var get_params = url.parse(request.url, true).query;
    if (Object.keys(get_params).length == 0)
    {
      response.setHeader('content-type', 'application/json');
      response.end(JSON.stringify(contacts.list()));
    }
    else
    {
     response.setHeader('content-type', 'application/json');
     stringify(contacts.query_by_arg(get_params.arg, get_params.value));
   }
 }); 

  app.get('/contacts/:number', function(request, response) {
   response.setHeader('content-type', 'application/json');
   response.end(JSON.stringify(contacts.query(request.params.number)));
 });

  app.get('/groups', function(request, response) {
   response.setHeader('content-type', 'application/json');
   response.end(JSON.stringify(contacts.list_groups()));
 });

  app.get('/groups/:name', function(request, response) {
   response.setHeader('content-type', 'application/json');
   response.end(JSON.stringify(
   contacts.get_members(request.params.name)));
 });

  app.use(function(req, res, next) {
    var err    = new Error('Not Found');
    err.status = 404;
    next(err);
  });


  http.createServer(app).listen(app.get('port'), function() {
   console.log('Express server listening on port ' + app.get('port'));
 });


  module.exports = app;

contacts.js script code:

var fs         = require('fs');
var mysql      = require('mysql');

var connection = mysql.createConnection({
  host     : '192.168.***.***', //Ip address of the server machine
  port     : '****', //Port number
  user     : 'ab',
  password : 'abc',
  database : 'MyDataBase'
});

//Read Json file
function read_json_file() {
  connection.connect();
  connection.query('SELECT 1 + 1 AS solution', function(err, rows, fields) {
    if (err) throw err;
    console.log('The solution is: ', rows[0].solution);
  });

connection.end();

   var file = './data/contacts.json';
   return fs.readFileSync(file);
}

//Parse the the file da
exports.list = function() {
   return JSON.parse(read_json_file());
};

exports.query = function(number) {
   console.log('contact Number is:: '+number);
   var json_result = JSON.parse(read_json_file());
   var result = json_result.result || [];
   for (var i = 0; i < result.length; i++) {
      var contact = result[i];
      if (contact.primarycontactnumber === number)    {
         return contact;
      }
   }
   return null;
};

exports.query_by_arg = function(arg, value) {
   var json_result = JSON.parse(read_json_file());
   var result = json_result.result || [];
   for (var i = 0; i < result.length; i++) {
      var contact = result[i];
      if (contact[arg] === value) {
         return contact;
      }
   }
   return null;
};

exports.list_groups = function() {
  var json_result = JSON.parse(read_json_file());
  var result       = json_result.result || [];
  var resultArray  = [];
  for (var i = 0; i < result.length; i++) {
   var groups = result[i].groups;
   for (var index = 0; index < groups.length; index++) {
      if (resultArray.indexOf(groups[index]) === -1) {
         resultArray.push(groups[index]);
      }
   }
}
return resultArray;
};

exports.get_members = function(group_name) {
   var json_result = JSON.parse(read_json_file());
   var result = json_result.result || [];
   var resultArray = [];
   for (var i = 0; i < result.length; i++) {
      if (result[i].groups.indexOf(group_name) > -1) {
         resultArray.push(result[i]);
      }
   }
   return resultArray;
};

Solution

  • Use mussel module https://github.com/patriksimek/node-mssql . Follow the samples.