How to execute an asynchronous function synchronously?

Question

Oracle

As I understand it, the connection.execute function is asynchronous. First, the interpreter goes through my forEach loop, and after that it starts executing connection.execute requests
. How can I make connection.execute requests be executed as the code is executed?

// massive-of-json-to-db

var oracledb = require('oracledb');     // To DB
var moment = require('moment');     
const fs = require("fs");               // FS

var FILEIN  = 'avgprice_bd-prepared.json';
var YEAR    = 2019;
var QUARTERNUMBER = 1;
var locationId;

var fileContent = fs.readFileSync(FILEIN, "utf8");     // File with massive of objects
var maxId = 0;  // !!

// Date-time locale initial
moment.locale('ru');

var dateOptions = {
    year:   'numeric',
    month:  'long',
    day:    'numeric',
    hour:   'numeric',
    minute: 'numeric',
    second: 'numeric'
};


// Check hyphen, replace to null
var replaceHyphen = (element) => ( element == '-'? null : element );

////////////////////////////////////////////

oracledb.getConnection(
  {
    user          : "system",
    password      : "test",
    connectString : "localhost/test"     
  },
  function(err, connection) {

        if (err) {
        console.error(err.message);
        return;
        } 

        var arr = fileStringToMassiveOfObjects(fileContent);
        
        // Passage through the array
        arr.forEach(function(item, i, arr) {

                    var now = new Date();

                    if (i<100) {
 

                            var d = moment().format('L');
                            d += " " + moment().format('LTS');   
                            
                            console.log(`d = ${d}`);
 
                            connection.execute(
                                 `INSERT INTO TEMP_AVG_PRICE (ID_CRE_RECORD, DATETIME, QUARTER, 
                                 "YEAR", state, locality
                                 ) VALUES 
                                (:id, TO_timestamp(:dt, 'DD.MM.YYYY HH24:MI:SS'), :qu, :y, :st, :loc
                                )`, 
                                {   id: maxId+1, dt: d, qu: QUARTERNUMBER, y: YEAR, 
                                    st:  replaceHyphen(arr[i]['Регион (субъект РФ)']), 
                                    loc: replaceHyphen(arr[i]['Населенный пункт (район)'])
                                },

                                // {autoCommit: true},
                                function(err, result) {
                                    if (err) {
                                        //console.error(err.message);
                                        //console.error('Error?');
                                        doRelease(connection);
                                        return;

                                    };
                                        console.log("Rows inserted " + result.rowsAffected);  
                                        connection.commit();                              
                                        //console.log(result.rows);
                                        doRelease(connection);
                                });

                            maxId++;

           
                        };      

        });   

        connection.commit();
        doRelease(connection);

  });


function doRelease(connection) {
  connection.close(
    function(err) {
      if (err)
        console.error(err.message);
    });
};


// From file-string to massive of objects
function fileStringToMassiveOfObjects(fileContent){     

    var arr = fileContent.split('},');    

    arr[0] = arr[0].substr(1);                                // Del first char [
    arr[arr.length - 1] = arr[arr.length - 1].slice(0, -1);   // Del end   char ]
   

    arr.forEach(function(item, i, arr) {

        if (i != (arr.length - 1)){
            item += '}';   // Add char } to the end of element   
        };             
        arr[i] = JSON.parse(item);

    });  

    return arr;

};

Answer 1

Async/await is the same as for await

Answer 2

You need to create an async function foo (connection,...) And inside it call a forEach loop in which you do await connection.execute instead of connection.execute.
Or pass async function(err, connection) {} as a callback to getConnection.