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Replace and update IDs using JavaScript stored procedure

Background:
I need to create a stored procedure in JavaScript (within CosmosDB) where: For every Feedback document, replace/update Feedback.id with new id
var NewID = "5678"
{
"Feedbacks" : [
{
"id": "1234"
}
{
"id": "1234"
}
]
}
This is what I am doing:
I have created a function called UpdateID and set the parameters to OldID and NewID. I am saying iterate through the document, and for every OldID value,, replace with the NewID. I am moreso familiar with Python so this is a bit different for me and I am not sure this is the correct approach.
For every iteration in doc.Feedbacks:
function UpdateID(OldID, NewID) {
if (Feedbacks.id = "OldID")
}
Any suggestion will be helpful

There are a handful of ways to write the javascript, but here's one way that should get on the right track:
function UpdateID(oldID, newID) {
//get just the records that need updating
var isAccepted = __.filter(
function(doc) {
return doc.Feedbacks && doc.Feedbacks.findIndex(function(feedback){
return feedback.id == oldID
}) > -1;
},
function (err, feed, options) {
if (err) throw err;
// Check the feed and if empty, set the body to 'no docs found'
if (!feed || !feed.length) {
var response = getContext().getResponse();
response.setBody('no docs found');
}
else {
//update the documents that have the old id
UpdateDoc(oldID, newID, feed)
}
});
if (!isAccepted) throw new Error('The query was not accepted by the server.');
}
//function based on https://stackoverflow.com/questions/36009939/documentdb-updating-multiple-documents-fails
function UpdateDoc(oldID, newID, documents) {
console.log("updating " + documents.length + " docs")
if (documents.length > 0) {
var document = documents[0];
// DocumentDB supports optimistic concurrency control via HTTP ETag.
var requestOptions = { etag: document._etag};
document.Feedbacks = document.Feedbacks.map(function(feedback){
if(feedback.id === oldID) {
feedback.id = newID;
}
return feedback;
});
// Update the document.
var isAccepted = __.replaceDocument(document._self, document, requestOptions, function(err, updatedDocument, responseOptions) {
if (err) {
responseBody.error = err;
throw err;
}
});
// If we hit execution bounds - throw an exception.
if (!isAccepted) {
responseBody.log += "Update not accepted";
response.setBody(responseBody);
}
else {
documents.shift();
if(documents.length > 0){
UpdateDoc(oldID, newID, documents);
}
}
}
}

node.js else if statement issue, close but no cigar

I have been on this for a good few hours.
I have the below function which reads from a table in my postgres db. It works as expected if there is stored strings in a column.
I can't get the 'else if' statement to work when there is no string in a field. To test this out I have a completely empty column under brand_code and its still executing the 'else' statement.
Now, I know why. There are 3 rows in the table. When I change the else if to === 3, it works as I'd like.
What code do I need to make the 'else if' statement work if the field is empty? (I plan to expand the SELECT statement later).
readCodes: function(callback) {
var pool = new pg.Pool(config.PG_CONFIG);
pool.connect(function(err, client, done) {
if (err) {
return console.error('Error acquiring client', err.stack);
}
client
.query(
'SELECT brand_code FROM public.voucher_codes',
function(err, result) {
if (err) {
console.log(err);
callback('');
} else if (result.rows.length === 0 ) {
console.log(result);
callback('');
} else {
let codes = [];
for (let i = 0; i < result.rows.length; i++) {
codes.push(result.rows[i]['brand_code']);
}
callback(codes);
};
});
});
}
}
Really struggled with this all day so any help is appreciated.
I am still learning. Prior to last week, I have never coded so apologies if this is amateur hour.

The problem here is that you are checking if it has returned rows or not, what you need instead is to check in each row if the field is empty
I suggest using underscore for iterating over each row:
_.each(result.rows,function(element, index){
if(element['brand_code'].length != 0){
codes.push(element['brand_code'])
}else{
console.log('empty field # results['+index+']')
}
})
CODE :
readCodes: function(callback) {
var pool = new pg.Pool(config.PG_CONFIG);
pool.connect(function(err, client, done) {
if(err){return console.error('Error acquiring client',err.stack);}
client.query(
'SELECT brand_code FROM public.voucher_codes',
function(err, result) {
if (err){console.log('[!] Error:',err); callback('');}
else if(result.rows.length == 0 ){
console.log('[!] Error:','No rows returned!');
callback('');
} else {
let codes = [];
_.each(result.rows,function(element, index){
console.log(element , index)
if(element['brand_code'].length != 0){
codes.push(element['brand_code'])
}else{
console.log('empty field # results['+index+']')
}
})
callback(codes);
}
});
});
}

Async write after select Pouchdb

I'm trying to check if an element exist before inserting it in my bdd.
I have to do this in order to (in the future) modify this existing element.
I'm using PouchDb and PouchDb-find with Node 6.9.1.
Actually I'm doing this:
for(var i = 0; i < 10;i++ ){
(function(_count, _pdb){
var count = _count;
var db = _pdb;
db.find({
selector: {numeroCandidat: parseInt(results[count].no_apb)}
}).then((result) => {
if(result.docs.length != 0){
console.log("l'étudiant existe");
}else{
console.log("l'étudiant n'existe pas");
var etudiant = {
"numeroCandidat": results[count].no_apb,
"nom": results[count].nom,
"numeroGroupe": "gr" + results[count].groupe,
"filiere": results[count].libelle,
};
db.post(etudiant).then((response) =>{
// handle response
console.log("STUDENT CREATED");
}).catch(function (err) {
console.log(err);
});
}
}).catch(function (err) {
});
})(i, this.pdb);
};
But the problem is : Due to the asynchronous version of my select query... if an element exists two times it appends that the second select occurred BEFORE the insertion of the first element, and I have this element two times in my database. I don't know how to deal with this one.

SO.. I'v found a workaround !
Simply create a function that I call recursivly after writting into my database.
Goodbye for loop.
var createStudents = function(_count, _pdb, _students){
if(_count >= 10) return;
console.log(_count);
var count = _count;
var db = _pdb;
var students = _students.slice(0);
db.find({
selector: {numeroCandidat: parseInt(students[count].no_apb)}
}).then((result) => {
if(result.docs.length != 0){
console.log("l'étudiant existe");
createStudents(++count,db,results);
}else{
var etudiant = {
"numeroCandidat": students[count].no_apb,
"nom": students[count].nom,
"numeroGroupe": "gr" + students[count].groupe,
"filiere": students[count].libelle,
"etudiantComms": [
{"commentaire": students[count].commentaire}
]
};
db.post(etudiant).then((response) =>{
// handle response
console.log("STUDENT CREATED");
createStudents(++count,db,results);
}).catch(function (err) {
console.log(err);
});
}
}).catch(function (err) {
});
}
createStudents(0,this.pdb,results);

socket.io emit firing three times

I'll start by saying I've found several similar issues posted on this site. None of them apply to my situation though.
I have a server and client (as is the norm with node.js/socket.io) and call emit a socket event when a button is pressed. This works fine... Except it seems to emit three times (at least the server runs the function three times). I've been staring at the code for way too long at this point and need another set of eyes.
Hopefully someone has an idea.
client code:
importJS('/js/pages/admin_base.js',function(){
var restartLMC = function(io){
toggleLoad();
var user = localStorage.getItem('User');
io.emit('restart_request',{session: user});
};
AdminIO = new io('http://localhost:26266');
AdminIO.on('restart_success',function(dat){
toggleLoad();
dropInfo(dat);
});
AdminIO.on('sendError',function(dat){
dropInfo(dat,{level: 'error'});
});
AdminIO.on('restart_fail',function(dat){
toggleLoad();
dropInfo(dat,{level: 'error'});
});
$('#restart').on('click',function(){
restartLMC(AdminIO);
});
});
Admin code:
process.stdout.write('\033c');
console.log('\x1b[36m', "Admin server starting...", '\x1b[0m');
var
ini = require('node-ini')
, conf = ini.parseSync('../config.ini')
, CS = require('../lm_modules/CoreSync.js')
, CoreSync = new CS()
, checkSession = function (session, callback) {
var res;
if (!CoreSync) { throw "Fatal error, there is no connection to the Core service!"; }
if (CoreSync.sessions) {
if (CoreSync.sessions[session]) {
res = CoreSync.sessions[session];
callback(res);
}
else {
CoreSync.sync('session', function (err, dat) {
if (CoreSync.sessions[session]) {
res = CoreSync.sessions[session];
callback(res);
} else { res = false; callback(res); }
});
}
} else {
res = false; callback(res);
}
if (res === "undefined") { callback(false); }
}
, runCMD = function(cmd,errCB,callback){
var
command
, args;
if(cmd.cmd){ command = cmd.cmd; } else { command = cmd; }
if(cmd.args){ args = cmd.args; }
const spawn = require('child_process').spawn;
const ex = spawn(command, args);
ex.stdout.on('data', (data) => {
callback(data);
});
ex.stderr.on('data', (data) => {
errCB(data);
});
ex.on('close', (code) => {
});
}
, executeCMD = function(cmd,callback){
const exec = require('child_process').exec
, cdw = (__dirname + '/../');
exec(cmd, {cwd: cdw}, (err, stdout, stderr) => {
if (err) {
callback(err,null);
return;
}
callback(stderr,stdout);
});
}
, io = require('socket.io').listen(26266) // can use up to 26485
console.log('\x1b[32m', "Admin server started.", '\x1b[0m');
console.log("Admin server listening at " + "http://" + conf["Server"]["binding"] + ":26266");
io.on('connection', function (socket) {
socket.on('restart_request', function(req){
console.log('Recieved restart request');
var success = false
, session = JSON.parse(req.session)
, sessionID = session.sessionID;
checkSession(sessionID, function (ses) {
if (ses === false) { console.error('CheckSession failed: No session exists'); return; }
if (ses.user.uuid !== session.uuid) { console.error('CheckSession failed: UUID mismatched'); return; }
if (ses.user.role < conf['Permissions']['lm_restart']){ socket.emit('restart_fail','Insufficient permissions.'); return; }
if(process.platform === 'win32'){
executeCMD('cd',function(err,res){
var errSent = false;
if(err){
console.error(err);
if(!errSent){ socket.emit('sendError','Restart failed'); }
errSent = true;
if(res === null){return;}
}
console.log(res);
socket.emit('restart_success','LM successfully restarted.');
});
}
else if(process.platform === 'linux'){
}
});
});
});

For those of you who may have seen this and found it a curious question/situation... I found two parts to this.
The first part is the $().on binding. For some reason (even though it's by no means called multiple times in the js code) adding unbind() in front of the binding resolved the issue in part... it cut the extra emits down from 3 to two (until I started another server app, then it went back up to three...)
The other part I found was that (for some reason) the socket.io connection is being duplicated as many times as there are socket servers running. More details on this issue here... I believe that once the cause for this is found, my issue will be resolved.

Push new field and value to json array object in node.js

I'm new to node.js. I need to display Name in jqgrid, but I stored only id of one document into another document.
Example
I have 2 documents like Student master and student mark document. I have to display mark details in jqgrid. In mark document I stored student id instead of name. How do I fetch the name and send a new object to jqgrid?
My code is as follows:
exports.getAllstudentsmark = function(req, callback)
{
studentsmarks.find(function(error, studentsmarks_collection) {
if( error ) callback(error)
else {
studentsmarks_collection.toArray(function(error, results) {
if( error ) callback(error)
else {
newresult = results;
for(i=0;i<results.length;i++)
{
newresult[i]['studentname'] = getStudentName(results[i].studentid);
}
console.log(newresult);
callback(null, newresult)}
});
}
});
}
var getstudentObjectId = function(id)
{
return student.db.bson_serializer.ObjectID.createFromHexString(id);
}
var getStudentName = function(id)
{
student.findOne({_id: getstudentObjectId (id)}, function(e, o){
console.log(o.name);
return o.name;
});
}
newresult[i]['studentname'] is always getting undefined. But if I log into getStudentName function I can get answer into getStudentName function.
My callback function is only getting this problem. How to resolve and get my result in an easy way. Please help any one.

try this inside your for loop
newresult.push({'studentname': getStudentName(results[i].studentid) });
exlpanation:
by the time you access newresult[i] it doesn't exist, so accessing studentname field of it is impossible

Your problem here is that you are not setting the name of the user into the array, but the return value of student.findOne, since this is an asynchronous method. Maybe try this thing
exports.getAllstudentsmark = function(req, callback)
{
studentsmarks.find(function(error, studentsmarks_collection) {
if( error ) callback(error)
else {
studentsmarks_collection.toArray(function(error, results) {
if( error ) callback(error)
else {
newresult = [];
for(i=0;i<results.length;i++)
{
getStudentName(results[i].studentid, function (studentName) {
newresult.push({studentname: studentName});
})
}
console.log(newresult);
callback(null, newresult)}
});
}
});
}
var getstudentObjectId = function(id)
{
return student.db.bson_serializer.ObjectID.createFromHexString(id);
}
var getStudentName = function(id, callback)
{
student.findOne({_id: getstudentObjectId (id)}, function(e, o){
console.log(o.name);
callback(o.name);
});
}
I hope it helps