Main connection with node-mssql

Question

I'm using node module "node-mssql" to connect a SQL Server.

I'm creating a bluebird promise and at the end this promise closes the connection. I did it because I don't know how to make a main connection, but I don't think opening/closing a connection each query is a good idea.

function  connection() {
    let promise = sql.connect('...');
    promise.catch(function (err) {
        console.log('********** Error on connecting **********');
        console.log(err);
        console.log('---------- Error on connecting ----------');
     })
     .finally(function () {
         sql.close();
     });
     return promise;
};

var query = connection().then(function() {
  new sql.Request()
  .input('foo', mssql.NVarChar, 'bar')
  .query('...')
  .then(function (out) {  
    //...
  })
  .catch(function (err) {
    console.log('********** Error on query **********');
    console.log(err);
    console.log('---------- Error on query----------');
  });
});

Is there some way to have main connection?

Answer 1

Well... I solve this adding flags and functions, below my code, I hope it helps, or comment if there is a better way.

var mssql = require('mssql');
var sql = {}
sql.connected = false;
sql.connect = function () {

let promise = mssql.connect(SQL.String);

promise.catch(function (err) {

    // handling error
    mssql.close();
    sql.connected = false;
});
    return promise;
};
sql.Request = function () {

return new Promise(function (resolve, reject) {


    if (!sql.connected) {

        sql.connect()
        .then(function () {

            sql.connected = true;
            resolve(new mssql.Request());
        });
    } else {

        resolve(new mssql.Request());
    }
});};