javascript - Cypress task undefined even though the promise is returned

Question

I used TypeScript and Cypress framework for the automation purpose. To retrieve the data from SQL Server I have tried with Cypress sql server but that is available only in JavaScript, due to that I have used the JavaScript MSSQL library to retrieve the values under plugin/index.js then called that function in the required TypeScript file. But it throws the error as undefined value during retrieval process even though I handled with promise. But the query output is successfully printed in the console (attached the image below)

I have tried the same with MYSQL there it works and in MSSQL it fails. What would be the reason, do I miss anything here? I have shared the trials and information below:

plugin/index.js

var mssql = require('mssql');

module.exports = (on, config) => {      
  on('task', {
    'createMSSQLConnection'(query) {
      var res = odsQueryDB(query)
      console.log(res)
      return res
    }
  });

function odsQueryDB(query) {
    return new Promise((resolve, reject) => {
      mssql.connect(db.ods,function(err){       
      if(err){ console.log(err) }
      var sqlServerRequest = new mssql.Request();
      sqlServerRequest.query(query, (error, recordset) => {
        if(error)  
          return reject(error)
        mssql.close();      
        console.log(recordset[0])
        return resolve(recordset)
       })
      })
    })
  }   
};

database.ts

class DBConnectionManager {

  getODSValueFromDB(){
      const query = `SELECT TOP(1) FIELD FROM TABLE`;
      cy.task('createMSSQLConnection',query).then(function (recordset:any) {
        if(recordset.length<1){
          throw new Error("There are no values in the results. Check the database data!")
        }
        let rec:any = recordset
        const results:any = Object.values(rec[0])
        cy.log(''+results[0])
   })
}

Console Output:

question from:https://stackoverflow.com/questions/65847239/cypress-task-undefined-even-though-the-promise-is-returned

Answer 1

The whole point of callbacks is that you don't have to return values anymore, just call the callbacks, giving the required info as parameter(s).

So, change this line:

return resolve(recordset)

To this instead:

resolve(recordset);

And it should work fine.