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Convert iterative function to recursive kind using javascript

I have written a function to pull stream data from the fetch API. I want to convert the function to a recursive one and would like to write it as an async function.
Here is the code which works but not asynchronous:
const productsStream = async () => {
const request = {
searchRange: ['fragrance', 'perfumery', 'cologne'],
exclusionCategory: ['discounted']
}
const response = await fetch('/products/stream', {
method: 'POST',
body: JSON.stringify(request)
});
const decoder = new TextDecoderStream();
const reader = response.body.pipeThrough(decoder).getReader();
let line = "";
while (true) {
const { done, value } = await reader.read();
let chunk = remainder + value;
let products = []
let newlineIndex;
while ((newlineIndex = chunk.indexOf("\n")) != -1) {
let item = chunk.substring(0, newlineIndex);
chunk = chunk.substring(newlineIndex);
if (chunk.length > 1) chunk = chunk.substring(1);
}
line = chunk;
products = []
if ( done ) break;
}
}
I'd welcome any help in converting this.

Incorrect loading order from local storage

I'm having problem with loading from local storage.
Here's a part of the code
const getTerminus = () => {
let terminus;
if (localStorage.getItem("terminus") === null) {
terminus = [];
} else {
terminus = JSON.parse(localStorage.getItem("terminus"));
}
let directions;
if (localStorage.getItem("directions") === null) {
directions = [];
} else {
directions = JSON.parse(localStorage.getItem("directions"));
}
terminus.forEach(async(stop) => {
let API_URL =
"https://ckan.multimediagdansk.pl/dataset/c24aa637-3619-4dc2-a171-a23eec8f2172/resource/d3e96eb6-25ad-4d6c-8651-b1eb39155945/download/stopsingdansk.json";
let response = await fetch(API_URL);
let data = await response.json();
const {
stops,
stopId,
stopName,
stopCode,
zoneId
} = data;
let input = stop;
let ID;
let dataArr = [];
for (let i = 0; i < stops.length; i++) {
if (
stops[i].stopName === input &&
stops[i].stopCode === directions[terminus.indexOf(input)] &&
stops[i].zoneId === 1
) {
ID = stops[i].stopId;
dataArr = [ID, stops[i].stopName];
}
}
API_URL = `https://ckan2.multimediagdansk.pl/delays?stopId=${ID}`;
response = await fetch(API_URL);
data = await response.json();
const {
delay,
estimatedTime,
routeId,
headsign
} = data;
let times = [];
let routeIds = [];
let headsigns = [];
for (let i = 0; i < delay.length; i++) {
times.push(delay[i].estimatedTime);
routeIds.push(delay[i].routeId);
headsigns.push(delay[i].headsign);
}
routeIds.push(" ");
times.push(" ");
const cardDiv = document.createElement("div");
cardDiv.classList.add("card");
const stopNameDiv = document.createElement("div");
stopNameDiv.classList.add("stop-name-div");
cardDiv.appendChild(stopNameDiv);
const stopNameSpan = document.createElement("span");
stopNameSpan.innerText = dataArr[1];
stopNameSpan.classList.add("stop-name-span");
stopNameDiv.appendChild(stopNameSpan);
const scheduleDiv = document.createElement("div");
scheduleDiv.classList.add("schedule-div");
cardDiv.appendChild(scheduleDiv);
if (headsigns.length !== 0) {
routeIds.unshift("Line");
headsigns.unshift("Direction");
times.unshift("Departure");
}
const lineSpan = document.createElement("span");
lineSpan.innerText = routeIds.join("\n");
lineSpan.classList.add("line-span");
scheduleDiv.appendChild(lineSpan);
const dirSpan = document.createElement("span");
dirSpan.innerText = headsigns.join("\n");
dirSpan.classList.add("dir-span");
scheduleDiv.appendChild(dirSpan);
const timeSpan = document.createElement("span");
timeSpan.innerText = times.join("\n");
timeSpan.classList.add("time-span");
scheduleDiv.appendChild(timeSpan);
const buttonsDiv = document.createElement("div");
buttonsDiv.classList.add("buttons-div");
cardDiv.appendChild(buttonsDiv);
const deleteButton = document.createElement("button");
deleteButton.innerHTML = '<i class="fas fa-trash"></i>';
deleteButton.classList.add("delete-button");
buttonsDiv.appendChild(deleteButton);
const dirButton = document.createElement("button");
dirButton.innerHTML = '<i class="fas fa-retweet"></i>';
dirButton.classList.add("reverse-button");
buttonsDiv.appendChild(dirButton);
stopList.appendChild(cardDiv);
});
};
document.addEventListener("DOMContentLoaded", getTerminus);
Terminus contains stop names, and directions contains direction codes.
On refresh, it fetches data from API based on stop name and direction, and displays a card with departure time etc.
The problem is, on closing and re-opening the page cards are sometimes displayed in a wrong order. I have found out, that as time between closing and opening lengthens, the probability of this occurring gets higher. After simple refresh everything is in correct order.
Does it have something to do with browser cache? Has anyone had similar issue or knows what's going on?

Alright, as #Yoshi stated, it was insequential promise error. I managed to fix it by using reduce().
Here are the threads that helped me
Resolve promises one after another (i.e. in sequence)?
Why Using reduce() to Sequentially Resolve Promises Works

Refactoring async functions in javascript

I have written a program to extract links to download photos in three steps:
The getPersons() function get the complete list of people to traverse.
Get the photos download links from the list of persons.
Download from the list created in step 2.
I am trying to refactor step 2 into an async function.
Is there an easy way to refactor second step into a function to make the code more readable?
Ideally, I would like to retrieve all the links and only then, start the download.
const axios = require("axios");
const cheerio = require("cheerio");
const url = "https://www.website.com";
const persons = [];
async function getPersons() {
await axios.get(url).then(response => {
const html = response.data;
const $ = cheerio.load(html);
const personList = $(".bio-btn");
console.log(personList.length);
personList.each(function() {
const link_raw = $(this).attr("href");
const link = url + link_raw;
const name = link_raw.replace("/bio/", "");
person.push({
name,
link
});
});
});
}
getPersons().then(function() {
persons.forEach(async function(person) {
var personLink = person.link;
await axios.get(personLink).then(response => {
const html = response.data;
const $ = cheerio.load(html);
const snapshots = $(".ratio-4-3");
snapshots.each(function() {
const pic = $(this).attr("style");
if (pic != undefined && pic.includes("biopicture")) {
var bioPhoto = s[1];
}
});
});
});
});

You are hardly getting much benefit out of your asynchronicity, as you end up making serial requests. I'd write it this way (untested):
async function getPersons() {
const response = await axios.get(url);
const html = response.data;
const $ = cheerio.load(html);
const personList = $('.bio-btn');
const persons = [];
personList.each(function() {
const link_raw = $(this).attr('href');
const link = url + link_raw;
const name = link_raw.replace("/bio/", "");
persons.push({
name,
link,
});
});
return persons;
};
async function getSnapshots() {
const persons = await getPersons();
const linkPromises = persons.map(person => axios.get(person.link));
const linkResponses = await Promise.all(linkPromises);
linkResults.forEach(response => {
const html = response.data;
const $ = cheerio.load(html);
const snapshots = $(".ratio-4-3");
// ...
});
}

I would refactor it like this. Removing .then() methods and the function keyword on anonymous functions makes the code look cleaner.
Using Promise.all() enables you to start all the downloads asynchronously which could be better than downloading images one by one.
const axios = require('axios');
const cheerio = require('cheerio');
const url = 'https://www.website.com';
async function getPersons() {
const response = await axios.get(url);
return extractPersonList(response);
}
// Step 1
function extractPersonList(response) {
const persons = [];
const html = response.data;
const $ = cheerio.load(html);
const personList = $('.bio-btn');
console.log(personList.length);
personList.each(() => {
const link_raw = $(this).attr('href');
const link = url + link_raw;
const name = link_raw.replace('/bio/', '');
persons.push({
name,
link
});
});
return persons;
}
async function getPhotos() {
const persons = await getPersons();
const promisies = persons.map(p => axios.get(p.link));
// Step 2
const responses = await Promise.all(promisies);
// Step 3
responses.forEach(response => {
const html = response.data;
const $ = cheerio.load(html);
const snapshots = $('.ratio-4-3');
snapshots.each(() => {
const pic = $(this).attr('style');
if (pic && pic.includes('biopicture')) {
var bioPhoto = s[1];
}
});
});
}
// Call getPhotos to start the process
getPhotos();

How to fetch api from the function which pushes each api in array?

I am trying to get API data so i can render it on Webpage using ReactJS. I tried many different ways to fetch api where its stored in array. But i am unable to do it.
Note:https://www.hatchways.io/api/assessment/workers/<worker_id> Here i'm looping so the
worker id gets add the of url.
const fetchAPI = e => {
let array = [];
const api2 = `https://www.hatchways.io/api/assessment/workers/`;
for (var i = 0; i <= 4; i++) {
array.push(api2 + i);
}
return array;
};
console.log(fetchAPI());
Thanks in advance.

You need to hit the url first. Async/Await would be a good choice.
<script>
async function check()
{
var arrayData =[];
var url = "https://www.hatchways.io/api/assessment/workers/";
for(var i=1;i<=4;i++)
{
const response = await fetch(url+""+i);
const myJson = await response.json();
arrayData.push(myJson);
}
console.log(arrayData)
}
check();
</script>

Use Promise.all for example:
const baseURL = 'https://jsonplaceholder.typicode.com';
const fetchUsers = fetch(`${baseURL}/users`);
const fetchPosts = fetch(`${baseURL}/posts`);
Promise.all([fetchUsers, fetchPosts]).then((responses) => {
const responsesToJson = responses.map(response => response.json());
return Promise.all(responsesToJson);
}).then((jsonResponse) => {
const [userResponse, postResponse] = jsonResponse;
console.log(userResponse);
console.log(postResponse);
});

Javascript fetch to variable issues

Mediocre javascript developer here and need some help..
I want to make a GET call to a url several times in a for loop.
I am trying to use fetch, but because of the promise/timing situation, I can't figure out how to make it work.
Below is the code and it's entirely possible that the fetch approach doesn't make sense for what I am trying to do. Would appreciate your help either helping me with code or telling me I am idiot and advising an alternative :)
var fromAmt = 100;
var fromOOP = 50;
var fromGM = 50;
var fromCur = "USD"
var toCur = ["USD","EUR","INR","GBP","SGD"];
var adjAmt = [];
async function getConversionAsync(fcur,tcur,amt)
{
let response = await fetch('https://data.fixer.io/api/convert?access_key=xyxyxyxyxyxyxy&from=' + fcur + '&to=' + tcur + '&amount=' + amt);
let data = await response.json()
return data;
}
for (i = 0; i < toCur.length; i++) {
getConversionAsync(fromCur,toCur[0].toString(),fromAmt)
.then(data => display(data));
}
function display(thing){
adjAmt.push(thing.result);
}
document.getElementById("something").innerHTML = adjAmt[0].toString();

In your example, document.getElementById("something").innerHTML = adjAmt[0].toString(); is executed before anything is pushed to adjAmt. You need to wait for the loop calls to finish before displaying a result, and for this you could wrap everything inside an async function.
const fromAmt = 100;
const fromOOP = 50;
const fromGM = 50;
const fromCur = 'USD';
const toCur = ['USD', 'EUR', 'INR', 'GBP', 'SGD'];
const adjAmt = [];
const getConversionAsync = async (fcur, tcur, amt) => {
const response = await fetch(`https://data.fixer.io/api/convert?access_key=xyxyxyxyxyxyxy&from=${fcur}&to=${tcur}&amount=${amt}`);
return response.json();
}
function display(thing) {
adjAmt.push(thing.result);
}
(async () => {
for (i = 0; i < toCur.length; i += 1) {
const data = await getConversionAsync(fromCur, toCur[0], fromAmt);
display(data);
}
document.getElementById('something').innerHTML = adjAmt[0].toString();
})();

Some small changes to make it work without the API call, but you'll want to access the correct index in your loop. I don't know what the exact output you're wanting here but in this case I just joined all the values in the array.
Additionally, the setting of innerHTML needs to be done once all the values are retrieved from the API, so I would even suggest doing that when the loop terminates, or some other "done" type event.
Additionally, you can use Promise.all instead of a loop, which is what I would go with personally.
var fromAmt = 100;
var fromOOP = 50;
var fromGM = 50;
var fromCur = "USD"
var toCur = ["USD", "EUR", "INR", "GBP", "SGD"];
var adjAmt = [];
async function getConversionAsync(fcur, tcur, amt) {
let response = await sampleRequest()
/* let data = await response.json() */
return response;
}
for (i = 0; i < toCur.length; i++) {
const data = getConversionAsync(fromCur, toCur[i].toString(), fromAmt).then(data => {
display(data)
})
}
function display(thing) {
adjAmt.push(thing);
document.getElementById("something").innerHTML = adjAmt.join(', ')
}
function sampleRequest() {
return new Promise((resolve, reject) => {
resolve(Math.round(Math.random() * 1000))
})
}
<div id="something"></div>