The Response from NodeJS has an offset of 1. E.g: 1 Query: A Output: Empty Response 2 Query: B Output: A 3 Query: C Output: B

If you need API/JSON Output, let me know.

I feels like i am just having a logical problem here. Or is there a command for this offset?

const express = require('express');

// Constants
const PORT = 8080;
const HOST = '0.0.0.0';


var resultQueryFilter = "";
var search_param = "";


var Connection = require('tedious').Connection;  
var config = {  
    server: '172.17.0.2',  
    authentication: {
        type: 'default',
        options: {
            userName: 'sa',
            password: 'PW' 
        }
    },
    options: {
        encrypt: false,
        useUTC: true,
        database: 'Park'  
    }
}; 
var connection = new Connection(config);  
connection.on('connect', function(err) {  
    // If no error, then good to proceed. 
    if(err) {
        console.log('Error: ', err)
      } else {
        console.log("Successful connection");
      } 
});
  

connection.connect();

var Request = require('tedious').Request;  
var TYPES = require('tedious').TYPES;  

function executeStatementQuery() {  
  request = new Request("SELECT * from dbo.users WHERE first_name like '%"  search_param  "%' FOR JSON PATH;", function(err) {  
  if (err) {  
      console.log(err);}  
  });  
  request.on('row', function(columns) {  
      columns.forEach(function(column) {  
        if (column.value === null) {  
          console.log('NULL');  
        } else {  
          resultQueryFilter = column.value   " ";  
        }  
      });  
      //console.log(resultQueryFilter);  
  });  
  connection.execSql(request);  
}


const app = express();
app.get('/company/search', (req, res) => {
  search_param = String(req.query.company_name);

  if (!search_param) {
    //No search param send
    console.log("Search request ist empty. Returning HTTP-406");
    res.status(406).send("Forbidden."); //Forbidden, as query cannot be empty
  } else {
    console.log("API Call with search req");
    console.log("Going to execute query");
    executeStatementQuery();
    console.log("Executed Query");
    console.log("Returning Output as JSON: "   String(resultQueryFilter));
    res.send(resultQueryFilter);
    console.log("Clearing old params");
    search_param = "";
    resultQueryFilter = "";
    console.log("Request done");

  }
});


app.listen(PORT, HOST, () => {
  console.log(`Running on http://${HOST}:${PORT}`);
});

cant post owtherwise: ererwearew rqe rwer fsfwe

CodePudding user response：

Your code uses global variables request and resultQueryFilter, which will be used concurrently by all the queries that you make. This cannot lead to correct (or even predictable) results.

Use local variables:

app.get('/company/search', function(req, res) {
  var search_param = String(req.query.company_name);
  var request = new Request("SELECT * from dbo.users WHERE first_name like '%"  search_param  "%' FOR JSON PATH;",
    function(err) {
      if (err) console.log(err);
    });
  var resultQueryFilter = "";
  request.on('row', function(columns) {
    columns.forEach(function(column) {
      if (column.value === null) {
        console.log('NULL');
      } else {
        resultQueryFilter  = column.value   " ";
      }
    });
  });
  request.on('done', function() {
    res.send(resultQueryFilter);
  });
  connection.execSql(request);
});