node-mssql: TypeError => 'validate' of undefined (prototype leakage)

Hi all.

Here is a part of my code:

var importDb = function() {
  sql.connect(connectionString).then(function() {
    console.log('connected');   ///////////////////////////////////// UNTIL HERE IS OK
    var query = 'SELECT TOP 10 * FROM ' + mRecord.view_path + ';'; // I'M SURE QUERY IS OK
    console.log('starting, with query: ' + query);
    var request = new sql.Request();
    request.query(query).then(function(recordset) {
      console.log('data successfully retrieved');  ///////////////// NEVER GETS EXECUTED
    }).catch(function(err) {
      console.log(err);
    });
  });
}

OK, to be honest, when I create a completely new project with this snippet, everything works perfectly but in my development project, the line where is .then(recordset) is throwing the error:

[TypeError: Cannot read property ‘validate’ of undefined]

Do you have a hint why? If you need more info, feel free to ask.

Node versions (nvm): 5.1.0 5.3.0 5.5.0

About this issue

Original URL
State: closed
Created 8 years ago
Comments: 22

Most upvoted comments

Applying the changes from #879 into my project worked for me

josealexandre on Jul 24, 2019

I’m not able to reproduce the issue. The error you get is because of invalid type of an input parameter. It’s happening on this line. But the request you’re creating in your sample has no parameters. Are you sure you’re getting this error with exactly this sample code?

This answer was the issue in my case. My teammate was using TYPES.NvarChar instead of TYPES.NVarChar

BTW, the sample code link is no longer pointing to the right line of code.

johndevedu on Sep 12, 2018

I also can reproduce this error when including adding a function to Object.prototype. The cause is mssql’s tedious.js, which does not check “hasOwnProperty” when looping through the names in this.parameters. Because the Object.prototype.[function] exists on this, an invalid output parameter is added. See example of problem code below:

for (let name in this.parameters) {
  let param = this.parameters[name]
  if (param.io === 1) {
    req.addParameter(param.name, getTediousType(param.type), parameterCorrection(param.value), {length: param.length, scale: param.scale, precision: param.precision})
  } else {
    req.addOutputParameter(param.name, getTediousType(param.type), parameterCorrection(param.value), {length: param.length, scale: param.scale, precision: param.precision})
  }
}

erika9star on Oct 19, 2018

I’m not able to reproduce the issue. The error you get is because of invalid type of an input parameter. It’s happening on this line. But the request you’re creating in your sample has no parameters. Are you sure you’re getting this error with exactly this sample code?

patriksimek on Oct 19, 2018