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Why am I intermittently writing partial arrays to files in Node with fs.readFileSync?

Context
I'm retrieving data from the ESPN API to fetch weekly NFL matchup data. So, I'm making 18 api calls each time I need to fetch this data to account for all 18 weeks in the NFL season. I'm then creating an array with the data I need from the responses to those calls and writing out 18 files that align with each week in the NFL season (week1.json, week2.json, etc.).
Problem
The problem is that when I call my endpoint, I am seeing 2 things intermittently, and not necessarily at the same time:
(1) Some of the json files(week1.json, week2.json, etc.) include only a portion of the expected array. So, instead of 16 objects in the array, I may see only 4, or only 6, etc. Why would I only see a portion of the response data written to the array that's ultimately written to the .json files?
(2) Not all files are written to each time the endpoint is called. So, I may see that only week1-week5's .json files are written. Why aren't all of them updated?
Problem Code
// iterate 18 times
for (let i = 0; i < 18; i++) {
let weekNumber;
weekNumber = i + 1;
const week = fs.readFileSync(`./pickem/week${weekNumber}.json`, 'utf8');
const weekJson = JSON.parse(week);
// empty weekJson.games array
weekJson.games = []
// get all items
axios.get(`https://sports.core.api.espn.com/v2/sports/football/leagues/nfl/seasons/2022/types/2/weeks/${weekNumber}/events?lang=en&region=us`)
.then(response => {
const schedule = [];
// get all items from response
const items = response.data.items
// console.log(response.data.items)
items.forEach(item => {
// make get call to $ref
axios.get(item.$ref)
.then(response => {
// get name
const name = response.data.name
// get date
const date = response.data.date
// get event id
const eventid = response.data.id
// get team ids
let team1 = response.data.competitions[0].competitors[0].id
let team2 = response.data.competitions[0].competitors[1].id
// create new object
const newObject = {
name: name,
date: date,
eventid: eventid,
team1: team1,
team2: team2
}
// add games for week
weekJson.games.push(newObject);
fs.writeFileSync(`./pickem/week${weekNumber}.json`, JSON.stringify(weekJson));
})
.catch(error => {
console.log(error)
})
})
}).catch(error => {
console.log(error)
})
}
Updated Code
router.get('/getschedules', (req, res) => {
async function writeGames() {
// iterate 18 times
for (let i = 0; i < 18; i++) {
let weekNumber;
weekNumber = i + 1;
const week = fs.readFileSync(`./pickem/week${weekNumber}.json`, 'utf8');
const weekJson = JSON.parse(week);
// empty weekJson.games array
weekJson.games = []
// get all items
// Add await keyword to wait for a week to be processed before going to the next one
await axios.get(`https://sports.core.api.espn.com/v2/sports/football/leagues/nfl/seasons/2022/types/2/weeks/${weekNumber}/events?lang=en&region=us`)
.then(async (response) => { // add async to be able to use await
const schedule = [];
// get all items from response
const items = response.data.items
console.log(response.data.items)
// Use standard loop to be able to benefit from async/await
for (let item of items) {
// make get call to $ref
// wait for an item to be processed before going to the next one
await axios.get(item.$ref)
.then(response => {
// get name
const name = response.data.name
// get date
const date = response.data.date
// get event id
const eventid = response.data.id
// get team ids
let team1 = response.data.competitions[0].competitors[0].id
let team2 = response.data.competitions[0].competitors[1].id
// create new object
const newObject = {
name: name,
date: date,
eventid: eventid,
team1: team1,
team2: team2
}
// add games for week
weekJson.games.push(newObject);
})
.catch(error => {
console.log(error)
})
}
// moved out of the for loop since you only need to write this once
fs.writeFileSync(`./pickem/week${weekNumber}.json`, JSON.stringify(weekJson));
}).catch(error => {
console.log(error)
})
}
}
writeGames();
})

Your issue might come from the fact that you are looping over an array of item that triggers parallel asynchronous calls and write weekJson before you get the entire data. (But theoretically your code should work if writeSyncFile is really synchronous, maybe there are locks on the file system that prevents node to write properly?)
You could try to make everything sequential and only write weekJson once instead of everytime you go over an item:
EDIT
I updated my original code proposition by keeping parallel calls and it worked for me (it's similar to OP's code but I only write the json file once per week).
Then I tried to run OP's code and it was working fine as well. So this makes me think that the problem isn't from the code itself but rather how it's called. As a pure node script, there doesn't seem to be any issue. But I just noticed that OP is using it server side as the result of an API call.
Having an API write so many JSON concurrently is probably not the best idea (especially if the api is called multiple times almost simultaneously). You could either
just return the games in the response
or precompute the results
or fetch and write them only once then cache the result to be reused
Then I wonder if due to the server context, there is not some kind of timeout since OP said that with my initial solution, only the first week was created.
const axios = require("axios");
const fs = require("fs");
async function writeGames() {
const writeWeekGamesPromises = [];
// iterate 18 times
for (let weekNumber = 1; weekNumber < 19; weekNumber++) {
// give week a default value in case the json file doesn't exist (for repro purpose)
let week = "{}";
try {
week = fs.readFileSync(`./pickem/week${weekNumber}.json`, "utf8");
} catch (e) {
console.log(`error reading week ${weekNumber} json file:`, e);
// file doesn't exist yet
}
const weekJson = JSON.parse(week);
// empty weekJson.games array
const games = [];
weekJson.games = games;
// get all items
// Add await keyword to wait for a week to be processed before going to the next one
writeWeekGamesPromises.push(axios
.get(
`https://sports.core.api.espn.com/v2/sports/football/leagues/nfl/seasons/2022/types/2/weeks/${weekNumber}/events?lang=en&region=us`
)
.then(async (eventListResponse) => {
// add async to be able to use await
const schedule = [];
console.log(JSON.stringify(eventListResponse.data),'\n');
// get all items from response
const items = eventListResponse.data.items;
// console.log(eventListResponse.data.items); // this seems to be useless since we log the whole data just above
// parallelize calls and wait for all games from a week to be fetched before writing the file
await Promise.all(
items.map((item) => {
// we return the promise so that Promise.all will wait for all games to be pushed before going on writing the file
return axios
.get(item.$ref)
.then((response) => {
// get name, date and eventid
const {name, date, id: eventid} = response.data;
// get team ids
let team1 = response.data.competitions[0].competitors[0].id;
let team2 = response.data.competitions[0].competitors[1].id;
games.push({ name, date, eventid, team1, team2 });
})
.catch((error) => {
console.log(error);
});
})
);
// Now that all game data is ready, write in the file
fs.writeFileSync(
`./pickem/week${weekNumber}.json`,
JSON.stringify(weekJson)
);
})
.catch((error) => {
console.log(error);
}));
}
// Waiting for all games from all weeks to be processed
await Promise.all(writeWeekGamesPromises);
}
async function runAndLogTime() {
const start = Date.now();
await writeGames();
console.log(`took ${(Date.now() - start) / 1000}s to write all json files`);
}
runAndLogTime();

Google Apps Script Working on backend but not on sheets

I am trying to create a script that pulls from the coin market cap API and displays the current price. The script is working fine on the back end when I assign the variable a value. However, when I try to run the function on sheets the returned value is null.
function marketview(ticker) {
var url = "https://pro-api.coinmarketcap.com/v1/cryptocurrency/quotes/latest?CMC_PRO_API_KEY=XXX&symbol=" + ticker;
var data = UrlFetchApp.fetch(url);
const jsondata = JSON.parse(data);
Logger.log(jsondata.data[ticker].quote['USD'].price)
}
My execution logs show that the scripts are running, but when when I use the function and try and quote ETH for example, the script is running for BTC.
When I do this on the backend and assign ETH the script works fine and returns the right quote. Any ideas on what I'm missing?

I did the same with coingecko API and add an issue having all my requests being rejected with quota exceeded error.
I understood that Google sheets servers IPs address were already spamming coingecko server. (I was obviously not the only one to try this).
This is why I used an external service like apify.com to pull the data and re-expose data over their API.
This is my AppScripts coingecko.gs:
/**
* get latest coingecko market prices dataset
*/
async function GET_COINGECKO_PRICES(key, actor) {
const coinGeckoUrl = `https://api.apify.com/v2/acts/${actor}/runs/last/dataset/items?token=${key}&status=SUCCEEDED`
return ImportJSON(coinGeckoUrl);
}
You need ImportJSON function, available here: https://github.com/bradjasper/ImportJSON/blob/master/ImportJSON.gs
Then in a cell I write: =GET_COINGECKO_PRICES(APIFY_API_KEY,APIFY_COINGECKO_MARKET_PRICES), you will have to create two field named APIFY_API_KEY and APIFY_COINGECKO_MARKET_PRICES in order for this to work.
Then register on apify.com, then you'll have to create an actor by forking apify-webscraper actor.
I set the StartURLs with https://api.coingecko.com/api/v3/coins/list, this will give me the total number of existing crypto (approx 11000 as of today), and number of page so I can run the request concurrently (rate limit is 10 concurrent requests on coingecko), then I just replace /list with /market and set the proper limit to get all the pages I need.
I use the following for the tasks page function:
async function pageFunction(context) {
let marketPrices = [];
const ENABLE_CONCURRENCY_BATCH = true;
const PRICE_CHANGE_PERCENTAGE = ['1h', '24h', '7d'];
const MAX_PAGE_TO_SCRAP = 10;
const MAX_PER_PAGE = 250;
const MAX_CONCURRENCY_BATCH_LIMIT = 10;
await context.WaitFor(5000);
const cryptoList = readJson();
const totalPage = Math.ceil(cryptoList.length / MAX_PER_PAGE);
context.log.info(`[Coingecko total cryptos count: ${cryptoList.length} (${totalPage} pages)]`)
function readJson() {
try {
const preEl = document.querySelector('body > pre');
return JSON.parse(preEl.innerText);
} catch (error) {
throw Error(`Failed to read JSON: ${error.message}`)
}
}
async function loadPage($page) {
try {
const params = {
vs_currency: 'usd',
page: $page,
per_page: MAX_PER_PAGE,
price_change_percentage: PRICE_CHANGE_PERCENTAGE.join(','),
sparkline: true,
}
let pageUrl = `${context.request.url.replace(/\/list$/, '/markets')}?`;
pageUrl += [
`vs_currency=${params.vs_currency}`,
`page=${params.page}`,
`per_page=${params.per_page}`,
`price_change_percentage=${params.price_change_percentage}`,
].join('&');
context.log.info(`GET page ${params.page} URL: ${pageUrl}`);
const page = await fetch(pageUrl).then((response) => response.json());
context.log.info(`Done GET page ${params.page} size ${page.length}`);
marketPrices = [...marketPrices, ...page];
return page
} catch (error) {
throw Error(`Fail to load page ${$page}: ${error.message}`)
}
}
try {
if (ENABLE_CONCURRENCY_BATCH) {
const fetchers = Array.from({ length: totalPage }).map((_, i) => {
const pageIndex = i + 1;
if (pageIndex > MAX_PAGE_TO_SCRAP) {
return null;
}
return () => loadPage(pageIndex);
}).filter(Boolean);
while (fetchers.length) {
await Promise.all(
fetchers.splice(0, MAX_CONCURRENCY_BATCH_LIMIT).map((f) => f())
);
}
} else {
let pageIndex = 1
let page = await loadPage(pageIndex)
while (page.length !== 0 && page <= MAX_PAGE_TO_SCRAP) {
pageIndex += 1
page = await loadPage(pageIndex)
}
}
} catch (error) {
context.log.info(`Fetchers failed: ${error.message}`);
}
context.log.info(`End: Updated ${marketPrices.length} prices for ${cryptoList.length} cryptos`);
const data = marketPrices.sort((a, b) => a.id.toLowerCase() > b.id.toLowerCase() ? 1 : -1);
context.log.info(JSON.stringify(data.find((item) => item.id.toLowerCase() === 'bitcoin')));
function sanitizer(item) {
item.symbol = item.symbol.toUpperCase()
return item;
}
return data.map(sanitizer)
}
I presume you are hiting the same issue I had with coinmarketcap, and that you could do the same with it.

You're not return ing anything to the sheet, but just logging it. Return it:
return jsondata.data[ticker].quote['USD'].price

async functions not executing in the correct order inside a map function

I have created an async function that will extra the data from the argument, create a Postgres query based on a data, then did some processing using the retrieved query data. Yet, when I call this function inside a map function, it seemed like it has looped through all the element to extra the data from the argument first before it proceed to the second and the third part, which lead to wrong computation on the second element and onwards(the first element is always correct). I am new to async function, can someone please take at the below code? Thanks!
async function testWeightedScore(test, examData) {
var grade = [];
const testID = examData[test.name];
console.log(testID);
var res = await DefaultPostgresPool().query(
//postgres query based on the score constant
);
var result = res.rows;
for (var i = 0; i < result.length; i++) {
const score = result[i].score;
var weightScore = score * 20;
//more computation
const mid = { "testID": testID, "score": weightScore, more values...};
grade.push(mid);
}
return grade;
}
(async () => {
const examSession = [{"name": "Sally"},{"name": "Bob"},{"name": "Steph"}]
const examData = {
"Sally": 384258,
"Bob": 718239,
"Steph": 349285,
};
var test = [];
examSession.map(async sesion => {
var result = await testWeightedScore(sesion,examData);
let counts = result.reduce((prev, curr) => {
let count = prev.get(curr.testID) || 0;
prev.set(curr.testID, curr.score + count);
return prev;
}, new Map());
let reducedObjArr = [...counts].map(([testID, score]) => {
return {testID, score}
})
console.info(reducedObjArr);
}
);
})();
// The console log printed out all the tokenID first(loop through all the element in examSession ), before it printed out reducedObjArr for each element

The async/await behaviour is that the code pause at await, and do something else (async) until the result of await is provided.
So your code will launch a testWeightedScore, leave at the postgresql query (second await) and in the meantime go to the other entries in your map, log the id, then leave again at the query level.
I didn't read your function in detail however so I am unsure if your function is properly isolated or the order and completion of each call is important.
If you want each test to be fully done one after the other and not in 'parallel', you should do a for loop instead of a map.

firestore query error for subcollections: rest.collection is not a function

I want to count the number of branches of all restaurants. "Branch" is a sub collection of "Restaurants". When I try to do this query, there is an error:
rest.collection is not a function
Here's my code. How can I fix it?
async function getBranch(){
const size = 0;
const restRef = await firebase.firestore().collection('Restaurants').get();
restRef.forEach((rest) => {
const branchRef = rest.collection('Branch').get();
size = size + branchRef.size();
})
return size;
}

you have to provide id of restaurants to get the subcollection. So better make reference for Restaurants and get all branches
async function getBranch(){
const size = 0;
const restRef = firebase.firestore().collection('Restaurants');
const restRes = await restRef.get();
restRef.forEach((rest) => {
const branchRef = await restRef.doc(rest.id).collection('Branch').get();
size = size + branchRef.size();
})
return size;
}

You could do as follow, by using Promise.all() (untested).
async function getBranch(){
let size = 0;
const restQS = await firebase.firestore().collection('Restaurants').get();
const promises = [];
restQS.forEach((rest) => {
promises.push(rest.collection('Branch').get());
});
const querySnapshotsArray = await Promise.all(promises);
querySnapshotsArray.forEach(qs => {
size += qs.size; // <= Note that size is a property of the QuerySnapshot, not a method
})
return size;
}
Another approach would be to query all your branch doc with a Collection group query, if the only collections named Branch are subcollection of Restaurants.
const branchQS = await firebase.firestore().collectionGroup('Branch').get();
return branchQS.size;
HOWEVER,
you should note that this implies that you read ALL the documents of ALL the (sub)collections each time you want to get the number of branch documents and, therefore, it has a cost.
So, if your collections have a lot of documents, a more affordable approach would be to maintain a set of distributed counters that hold the number of documents. Each time you add/remove a document, you increase/decrease the counters.
See here in the doc for more details, as well as this answer.

Vue.js combine data from RESP API

I need combine multple API calls on a final object, this because API have limits to be consumed, any have an idea how is possible combine multiple calls in same final object, next is an example of my code, I need all data in this.lista but is not working:
created(){
this.$http.get('/api/transactions?senderId=8642612272713533685S&limit=1&offset=000')
.then( function(res){
console.log(res.body.count);
let limit = Math.ceil(res.body.count/1000);
console.log(limit);
let m = {};
let off = 0;
for (var i = 0; i <= limit; i++) {
this.$http.get('/api/transactions?senderId=8642612272713533685S&limit=1000', {params:{offset: off}})
.then( function(data){
this.lista = { ...this.lista, ...data.body.transactions }
} )
off = off + 1000;
}
}
);
}
any help will be appreciated

Using Promise.all is most likely what you are looking for. I will write just enough code for you to understand where to go.
// Populate your array array with URLs you want to get
let urls = ["url1", "url2", "...and so on"];
// Make into web request promises
let httpReqPromises = urls.map( url => this.$http.get(url) )
// Wait for all of them to resolve
Promise.all(httpReqPromises).then(allResponses => {
// Put them all together
this.lista = allResponses.reduce((a, b) => ({...a, ...b}, {})
})
The only work I leave up to you is how you populate the url variable.