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Sequelize.fn : Constructing the update argument outside the call

Issue Description
I'm currently trying to make updates on passwords using sequelize.fn.
I've seen numerous sites, including the Sequelize's manual, yet I found too few articles that approaches my case, and none of them seems to solve it.
Moreover, the function to encrypt the passwords need nested function, so I need to gradually construct the nested function
by putting the successive arguments into variables.
I have not found anything on constructing the functions, thus using sequelize.fn outside the arguments of the functions find and updates.
Additional context
In my case, " crypt('password', gen_salt('bf', 4)) " (in Postgres) needs to become
sequelize.fn('crypt', 'password', sequelize.fn('gen_salt', 'bf', 4)) and to be stored into a variable
When I inject it into the update function, an Fn Object is injected, and the result in the database seems to be a memory address instead of the result of the crypt function.
I may post a code example so you can have a better understanding of what I'm trying to do and I think should be added into the documentation
I did not made this doc issue to resolve my issue, only to point out what I think is lacking in the documentation
I will ask StackOverflow for help regarding my issue.
//Take a format and a value, and applies the functions inside the format onto the value
function recursSequelizeFn (format, value) {
const sequelize = db.sequelize;
let nextId = 0;
let matches;
let finalArgs = {};
//The RegEx finds the function calls of which parameters aren't functions themselves
//As the format string is modified on each loop, I need to initialize the RegEx on each loop
while ((matches = (/(\w+)\(([^(,)]+)?(?:,([^(,)]+))*\)/g).exec(format)) !== null) {
//matches[0] is the whole expression
//matches[1] is the function's name
//matches[>=2] are the arguments
let func = matches[1];
let args = matches.slice(2);
for (let argNo in args) {
//Transforms DB's columns into Sequelize-interpreted columns
//I do not check the column that is found, because I do not have others columns than the one that is being treated
args[argNo] = args[argNo].replace(/seqCol_(\w+)/g, (correspondance, p1, decalage, chaine)=>{return value;});
//If the parameter was previously saved, we replace its reference by its value
args[argNo] = args[argNo].replace(/(#\d+)/g, (correspondance, p1, decalage, chaine)=>{return finalArgs[p1];});
}
//finally, we save the value of the function and replace the whole expression by a reference
finalArgs['#'+nextId]=sequelize.fn(func, ...args);
format = format.replace(matches[0], '#'+nextId);
nextId++;
}
//When the treatment is finished, we return the last value saved into the array
//Or we return the original value if we have not made any change (the array will be empty)
return finalArgs['#'+(nextId-1)]||value;
}
Object.keys(req.message.attributes).map((key)=>{
//req.message.attributes[key] contains the formatting needed to be put onto the value
//e.g. crypt(password, gen_salt('bf', 4))
//req.body[key] contains the value
//e.g. '1234'
let seqValue = util.recursSequelizeFn(req.message.attributes[key], req.body[key]);
req.body[key] = seqValue;
});
//mainModel is a sequelize model
mainModel.update(req.body, {where: {id:req.params.id}, logging:console.log})
.then() //...

Splitting string results in infinite loop

I need to split this string and loop through the resulting array. However, even though my result string array has only 3 items, my loop goes to infinity.
I am probably missing something, but I can not see it at this point.
Here is the code:
CustomizeDashboardService.getCustomizedDashboard().then(function (res) {
console.log(res);
var sensors = res.sensor.split(',');
var devices = res.uuid.split(',');;
console.log("CS: S",sensors) // I Can see these 2 arrays have only 3 items each,
console.log("CS: D",devices) // but when it goes into my for loop, it iterates to indefinite
for(i=0;i<devices.length-1;i++){
console.log("girdi") // I see this is logging more than 1000 times
var index = findIndex(devices[i]);
var obj = {
device:self.deviceList[index],
sensor: sensors[i]
}
self.customizedSensors.push(obj);
}
console.log("customized sensors",self.customizedSensors);
})

Your loop has for(i=0;i<devices.length-1;i++) which means the iteration variable is not locally scoped. If somewhere else the i value is changed then it can cause issues. As a matter of habit, always var your iterator variable unless you have a very specific reason not to (such situations do exist but are fairly rare). To avoid other issues I would recommend looking through all of your code and making sure you have the var in there.

Javascript push() replacing element instead of appending

Here's a function I have written to add words to local storage using Javascript. In case you're wondering, this is my attempt at building a search history functionality for a simple dictionary lookup site.
function add2local(entry){
var l = localStorage.length;
if(l==0){
var lu = [entry];
localStorage.setItem("w", JSON.stringify(lu));
}
else {
var lu = JSON.parse(localStorage.getItem("w")); alert(lu);
lu.push(entry); alert(lu);
}}
My understanding is the this function would keep appending its argument to local storage every time it's called. So, the first time I call it, I send it the word pirate. This gets added to the array and subsequently to the local storage as expected. The first alert() (the alert() functions are solely being used for testing) confirms this. The second time, I call it with the word vampire. Now, going by the function's logic, vampire should be appended to the array and thus the second alert() should output "pirate, vampire." And so it does.
But the third time around, say, I call the function with the word foo. This time around, it should output "pirate, vampire, foo" but instead shows "pirate, foo". Every subsequent call simply replaces the second word with the new word instead of appending it. What might I be doing wrong here? Am I misunderstanding how push() works?

The if condition and logic is incorrect; it is irrelevant how many items localStorage has, but it is very important to re-save the modified array.
In any case, I suspect an impl. might look as so:
function add2local(entry){
// load entries - if there are none, we simulate an empty array to load
var lu = JSON.parse(localStorage.getItem("w") || "[]");
// add new entry
lu.push(entry);
// write back - so change is not lost between function calls
localStorage.setItem("w", JSON.stringify(lu));
// return all local entries saved - for use from the caller
return lu;
}

Why check the storage length? You don't care. Fetch the key and if it's null then default to empty array.
function add2local (entry) {
var key = "w"
var value = localStorage.getItem(key)
if (value) {
value = JSON.parse(value)
} else {
value = []
}
value.push(entry)
localStorage.setItem(key, JSON.stringify(value))
}

Confusion around closure/scope

Today while working with some JS I had a bug in my code. I was able to resolve it but I don't really understand why the change I made works. All I can guess is that it comes down to either closure or variable scope.
I was trying to build up a nested hash of arrays like so:
var maxNumberOfPairs = 2;
var container = {};
var pairsHash = {};
$.each(["nurse", "doctor", "janitor", "chef", "surgeon"], function(index, role) {
for(var i = 0; i < maxNumberOfPairs; i++){
var pairIdSubString = "attribute_" + i + "_" + role;
pairsHash["attribute_" + i] = [pairIdSubString + "_night", pairIdSubString + "_day"];
}
container [role] = pairsHash;
});
If you run this you get a nice nested output inside container but when you look at each array in the hash you get a weird behaviour with the string produced.
Each one has the last role in each string like so:
"attribute_0_surgeon_night"
If you log out the variable pairIdSubString it correctly has the role in the string, but as soon as this is added to pairHash it just uses the last element in the $.each array.
I was able to fix it by moving pairsHash inside the $.each but outside the for loop.
Can anyone explain to my why the output was different after moving it inside the each?
Thanks

It actually has to do with reference vs value. When its outside the each you are operating on the same object over and over so every time you set it to the container you are just setting a reference to the same object that is constantly changing. So every reference in container after the loop is the last state of the pairsHash because they all point to the same object.
When you put the pairsHash in the each it is reinitialized every time so they all point to different memory addresses. Not the same one since a new one is created every loop.
To further clarify all objects are just references to a memory address In JavaScript so in order to get new one you need to initialize or to pass by value to a function clone it.

Javascript variable acts like reference instead of object

I have an issue I can't quite put my finger on.
var records = dataView.getItems();
for (var i = 0; i < records.length; i++) {
var date = records[i].RecordCreated;
records[i].RecordCreated = new Date(parseInt(date.replace('/Date(', '')));
}
records = JSON.stringify(records);
This is a small loop that takes existing data from a SlickGrid dataview and converts the /Date(###)/ format to a proper date format in order to be deserialized on the server. This works fine.
The weird issue is that the var records = dataView.getItems(); definition is acting more like a reference than an individual, unique, object. Consider the following code:
var records = dataView.getItems();
// Debug Code [A]
console.log(records);
console.log(dataView.getItems());
for (var i = 0; i < records.length; i++) {
var date = records[i].RecordCreated;
records[i].RecordCreated = new Date(parseInt(date.replace('/Date(', '')));
}
// Debug Code [B]
console.log(records);
console.log(dataView.getItems());
records = JSON.stringify(records);
The console logs at [B] are both identical, where one would expect them to be different. Meaning instead of seeing the second log with unchanged /Date(###)/ format dates, proper date objects are printing.
Even stranger is that at [A] the console logs are printing as if the loop ran asynchronously and finished prior to the console.log() command was called.
This is all wrapped in a function with some conditional statements to do different loops, nothing crazy. What I need to know is how/why the records definition is not working as per usual (a unique variable in memory, that can be edited without affecting the original object).
Solution
So the problem was that records was receiving the original object from the SlickGrid library. What I did to fix the issue was clone the object before assigning it to records.
Clone function:
function clone(obj) {
if (obj == null || typeof (obj) != 'object')
return obj;
var temp = new obj.constructor();
for (var key in obj)
temp[key] = clone(obj[key]);
return temp;
}
Usage:
var __data = dataView.getItems();
records = clone(__data);
Hope this helps anybody else viewing this question in the future.

looks like your records variable is an array being returned from dataView.getItems(). This variable IS a reference to the array object, so changing things on that object will be reflected in all the references to the object.

You should ensure that dataView.getItems() calls Array.protototype.slice on any collection it is returning