I'm trying to figure out a more efficient away to create the list items in the DOM.
At the moment the list is created as each API request is made.
I'm pushing each object into its own Array, I would like to create the list once all the data has loaded.
Additionally i'm using Webpack and Babel.
let streamApi = 'https://wind-bow.glitch.me/twitch-api/streams/';
let twitchUsers = ['ESL_SC2', 'OgamingSC2', 'freecodecamp', 'noobs2ninjas', 'comster404'];
let streamByUser = [];
window.onload = function() {
//Make a API request for each user and store in an array
twitchUsers.map((user) => {
fetch(streamApi + user, {method: 'GET'})
.then(response => response.json())
.then(json => {
streamByUser.push(json);
let uL = document.getElementById("user-list");
let listItem = document.createElement("li");
listItem.className = "list-group-item";
if (json.stream === null) {
listItem.innerHTML = "null";
} else {
listItem.innerHTML = json.stream.channel.display_name;
}
uL.appendChild(listItem);
});
});
};
UPDATE:
All is working!
Not tested but I hope it should work as expected.
const streamApi = "https://wind-bow.glitch.me/twitch-api/streams/";
const twitchUsers = [
"ESL_SC2",
"OgamingSC2",
"freecodecamp",
"noobs2ninjas",
"comster404"
];
const twitchUsersStreams = twitchUsers.map(user =>
fetch(streamApi + user, { method: "GET" }).then(res => res.json())
);
let streamByUser = [];
window.onload = function() {
Promise
.all(twitchUsersStreams)
.then(everythingArray => {
//do something with everythingArray after all the requests resolved
})
.catch(err => {
// As soon as any of the 'fetch' results in promise rejection
});
};
I would probably do something like this because I really like to decompose a task into small functions that reduce the need for inline comments and keep mutable state to a minimum.
const streamApi = 'https://wind-bow.glitch.me/twitch-api/streams/';
const twitchUsers = ['ESL_SC2', 'OgamingSC2', 'freecodecamp', 'noobs2ninjas', 'comster404'];
window.onload = async function () {
const list = document.getElementById("user-list");
const addToList = list.appendChild.bind(list);
const twitchStreams = await fetchUsers(twitchUsers);
twitchStreams.map(toListItem).forEach(addToList);
};
async function fetchUser(user) {
const response = await fetch(`${streamApi}${user}`, {method: 'GET'});
return response.json();
}
function fetchUsers(users) {
return Promise.all(users.map(fetchUser));
}
function toListItem(user) {
const listItem = document.createElement("li");
listItem.className = "list-group-item";
listItem.innerHTML = user.stream !== null
? user.stream.channel.display_name
: "null";
return listItem;
}
Related
I am making a function for firebase cloud functions, I want a function to be called every time a new document is created in "posts". I want this function to perform the tasks that I put inside the "onCeatePost" function.
The problem I have is that I'm not sure if this is the correct way to structure such a function.
In several firebase examples I have seen that it is always called return _; or return null; at the end of a task, but I don't know how to structure the function so that all the tasks are carried out, could someone help me to restructure my function or tell me what is wrong please.
There are several if statements in the function, if the created publication does not comply with them, I would like it to skip them but continue with the other tasks that I put inside the function.
I don't know if it's too much to ask, but I'm new to this language and I haven't been able to find the answer I'm looking for. Thank you!
exports.onPostCreate = functions.firestore.document("/posts/{postId}").onCreate(async (snap) => {
const post = snap.data();
if (post) {
try {
const topic = post.topic;
const contentForFeed = post.contentForFeed;
const uid = post.uid;
const previous = post.prev;
await db.collection("users").doc(uid).update({"stats.posts": admin.firestore.FieldValue.increment(1)});
if (topic) {
await db.collection("topics").doc(topic.id).collection("user-authors").doc(uid).set({"date": snap.createTime});
}
if (contentForFeed == true) {
const userPath = db.collection("users").doc(uid);
await userPath.update({"stats.lastUpdate": snap.createTime});
}
if (previous) {
const previousId = previous.id;
const previousUid = previous.uid;
const refPrev = db.collection("posts").doc(previousId);
await db.runTransaction(async (t) => {
const doc = await t.get(refPrev);
const priority = doc.data().stats.date;
const newDate = new admin.firestore.Timestamp(priority.seconds + 120, priority.nanoseconds);
await db.collection("posts").doc(previousId).update({"newDate": newDate});
});
if (previousUid != uid) {
const path = db.collection("users").doc(uid).collection("user-posts");
const dataToSet = {"timestamp": snap.createTime, "uid": uid, "postId": onReplyToPostId};
await path(dataToSet);
}
}
} catch (err) {
functions.logger.log(err);
}
} else {
return null;
}
});
You'll find below the adapted code (untested) with 4 corrections.
Here are explanations for the two most important ones:
(Correction 2) In a transaction you need to use the transaction's update() method and not the "standard one"
(Correction 4) When all the asynchronous work is complete you need to return a value or a Promise. See this documntation page for more details.
exports.onPostCreate = functions.firestore
.document('/posts/{postId}')
.onCreate(async (snap) => {
const post = snap.data();
if (post) {
try {
const topic = post.topic;
const contentForFeed = post.contentForFeed;
const uid = post.uid;
const previous = post.prev;
await db
.collection('users')
.doc(uid)
.update({
'stats.posts': admin.firestore.FieldValue.increment(1),
});
if (topic) {
await db
.collection('topics')
.doc(topic.id)
.collection('user-authors')
.doc(uid)
.set({ date: snap.createTime });
}
if (contentForFeed == true) {
const userPath = db.collection('users').doc(uid);
await userPath.update({ 'stats.lastUpdate': snap.createTime });
}
let previousUid; // <= Correction 1
if (previous) {
const previousId = previous.id;
previousUid = previous.uid; // <= Correction 1
const refPrev = db.collection('posts').doc(previousId);
await db.runTransaction(async (t) => {
const doc = await t.get(refPrev);
const priority = doc.data().stats.date;
const newDate = new admin.firestore.Timestamp(
priority.seconds + 120,
priority.nanoseconds
);
t.update(refPrev, { newDate: newDate }); // <= Correction 2
});
if (previousUid != uid) {
const path = db
.collection('users')
.doc(uid)
.collection('user-posts');
const dataToSet = {
timestamp: snap.createTime,
uid: uid,
postId: onReplyToPostId,
};
await path.add(dataToSet); // <= Correction 3
}
}
return null; // <= Correction 4
} catch (err) {
functions.logger.log(err);
}
} else {
return null;
}
});
I have some code that when you console.log it, it looks like the image below:
The code I am running is as follows:
onClick={() => {
const stream = fetch(
'https://lichess.org/api/games/user/neio',
{ headers: { Accept: 'application/x-ndjson' } }
);
const onMessage = obj => {
console.log('test', obj);
};
const onComplete = () =>
console.log('The stream has completed');
stream.then(readStream(onMessage)).then(onComplete);
}}
export const readStream = processLine => response => {
const stream = response.body.getReader();
const matcher = /\r?\n/;
const decoder = new TextDecoder();
let buf = '';
const loop = () =>
stream.read().then(({ done, value }) => {
if (done) {
if (buf.length > 0) processLine(JSON.parse(buf));
} else {
const chunk = decoder.decode(value, {
stream: true,
});
buf += chunk;
const parts = buf.split(matcher);
buf = parts.pop();
for (const i of parts) processLine(JSON.parse(i));
return loop();
}
});
return loop();
};
export default readStream;
What I am trying to do is build a parent object that contains all these individual rows of data.
I'm new at promises and fetch etc. So currently, I have no idea on how to build this parent object that contains each individual row.
Any suggestions?
Can't you have a global array and add items to it like:
var arrCollection = [];
...
const onMessage = obj => {
arrCollection.push(obj);
};
You can have an object with those items doing like:
var objCollection = { items: arrCollection };
I wrote an Async/Await function to return promises for drivers report and analysis.
I have three different promise API files I extracted details from to do my analysis. However running test ith jest I get the error
Timeout - Async callback was not invoked within the 5000ms timeout specified by jest.setTimeout.Error:
I have refactored my code more than three times in two days but the error returns.
I will like to know how to manage my promises, perhaps there is something am not doing well and I am keen on this for optimization.
Is there a way to manage the promises in the code below to bypass the jest error?
any other suggestion will be highly appreciated.
NB: sorry I have post all the code for better insight.
code
const { getTrips } = require('api');
const { getDriver } = require('api')
const { getVehicle } = require('api')
/**
* This function should return the data for drivers in the specified format
*
* Question 4
*
* #returns {any} Driver report data
*/
async function driverReport() {
// Your code goes here
let trip = await getTrips()
trip = trip.map(item => {
item.billedAmount = parseFloat(item.billedAmount.toString().replace(',', '')).toFixed(2);
return item;
})
let getId = trip.reduce((user, cur) => {
user[cur.driverID] ? user[cur.driverID] = user[cur.driverID] + 1 : user[cur.driverID] = 1
return user
}, {})
// console.log(getId)
let mapId = Object.keys(getId)
// console.log(mapId)
let eachTripSummary = mapId.reduce((acc, cur) => {
let singleTrip = trip.filter(item => item.driverID == cur)
acc.push(singleTrip)
return acc
}, [])
// eachTripSummary = eachTripSummary[0]
// console.log(eachTripSummary)
// console.log(trip)
let reducedReport = eachTripSummary.reduce(async(acc, cur) =>{
acc = await acc
// console.log(acc)
let user = {}
let cash = cur.filter(item => item.isCash == true)
// console.log(cash.length)
let nonCash = cur.filter(item => item.isCash == false)
let driverSummary = await getDriverSummary(cur[0]['driverID'])
let trips = []
let customer = {}
cur[0].user ? (customer['user'] = cur[0]['user']['name'], customer['created'] = cur[0]['created'], customer['pickup'] = cur[0]['pickup']['address'],
customer['destination'] = cur[0]['destination']['address'], customer['billed'] = cur[0]['billedAmount'], customer['isCash'] = cur[0]['isCash']) : false
trips.push(customer)
let vehicles = []
if(driverSummary == undefined){
// console.log(cur)
user = {
id: cur[0]['driverID'],
vehicles: vehicles,
noOfCashTrips: cash.length,
noOfNonCashTrips: nonCash.length,
noOfTrips: cur.length,
trips: trips
}
acc.push(user)
// console.log(user)
return acc
}
let driverInfo = driverSummary[0]
let vehicleInfo = driverSummary[1]
let { name, phone } = driverInfo
let { plate, manufacturer } = vehicleInfo[0]
// console.log(plate)
let vpm = {
plate,
manufacturer
}
vehicles.push(vpm)
// console.log(cash.length)
user ={
fulName: name,
phone,
id: cur[0]['driverID'],
vehicles: vehicles,
noOfCashTrips: cash.length,
noOfNonCashTrips: nonCash.length,
noOfTrips: cur.length,
trips: trips
}
acc.push(user)
// console.log(acc)
return acc
}, [])
// reducedReport.then(data =>{console.log(data)})
return reducedReport
}
async function getDriverSummary(param) {
let driverDetails = await getDriver(param)
.then(data => {return data}).catch(err => {return err})
// console.log(driverDetails)
let vehicleDetails;
let { vehicleID } = driverDetails
if(driverDetails != "Error" & vehicleID != undefined){
// console.log(vehicleID)
vehicleDetails = vehicleID.map(async item => {
let vehicleSummary = getVehicle(item)
return vehicleSummary
})
// console.log(await vehicleDetails)
return await Promise.all([driverDetails, vehicleDetails])
}
}
driverReport().then(data => {
console.log(data)
})
module.exports = driverReport;
Use jest.setTimeout(30000); to increase the timeout. It will increase the timeout globally.
// jest.config.js
module.exports = {
setupTestFrameworkScriptFile: './jest.setup.js'
}
// jest.setup.js
jest.setTimeout(30000)
Or you can use user test example like this
describe("...", () => {
test(`...`, async () => {
...
}, 30000);
});
I tried to make my web-crawler to have a loop to crawl the webpage from 1 to around 500. But the result does not include any directed one but to return an only void array.
This code is based on cheerio, jQuery, and axios. JavaScript.
const axios = require("axios");
const cheerio = require("cheerio");
const log = console.log;
const getHtml = async() => {
var i=0
while (i<493){
try {
return await axios.get("https://playentry.org/ds#!/qna?sort=created&rows=20&page="+i);
} catch (error) {
console.error(error);
}
}
};
getHtml()
.then(html => {
let ulList = [];
const $ = cheerio.load(html.data);
const $bodyList = $("div.discussContentWrapper div.discussListWrapper table.discussList").children("tr.discussRow");
$bodyList.each(function(i, elem){
ulList[i] = {
title:$(this).find('td.discussTitle div.discussTitleWrapper'),
writer:$(this).find('td.discussTitle td.discussViewCount'),
viewcount:$(this).find('td.discussTitle td.discussViewCount'),
likecount:$(this).find('td.discussTitle div.discussLikeCount'),
date:$(this).find('td.discussTitle td.discussDate'),
};
});
const data = ulList.filter(n => n.title);
return data;
})
.then(res => log(res));
The output is '''[]''' or '''[ [] ]''' with no real outputs.
Thanks for your help in advance.
Can someone provide an example on how to use the beforeEach? http://www.node-tap.org/api/
Ideally, an example of the promise version, but a callback version example would also be nice.
Here is a test I created which works fine:
'use strict';
const t = require('tap');
const tp = require('tapromise');
const app = require('../../../server/server');
const Team = app.models.Team;
t.test('crupdate', t => {
t = tp(t);
const existingId = '123';
const existingData = {externalId: existingId, botId: 'b123'};
const existingTeam = Team.create(existingData);
return existingTeam.then(() => {
stubCreate();
const newId = 'not 123'
const newData = {externalId: newId, whatever: 'value'};
const newResult = Team.crupdate({externalId: newId}, newData);
const existingResult = Team.crupdate({externalId: existingId}, existingData);
return Promise.all([
t.equal(newResult, newData, 'Creates new Team when the external ID is different'),
t.match(existingResult, existingTeam, 'Finds existing Team when the external ID exists')
]);
});
})
.then(() => {
process.exit();
})
.catch(t.threw);
function stubCreate() {
Team.create = data => Promise.resolve(data);
}
Before I do anything, I want to persist existingTeam. After it's saved, I want to stub Team.create. After these two things, I want to start actually testing. I think it would be cleaner if instead of using a Promise.all or perhaps duplicating the test code, I could use beforeEach.
How would I convert this to use beforeEach? Or what is an example of its usage?
Simple, just return promise from callback function
const t = require('tap');
const tp = require('tapromise');
const app = require('../../../server/server');
const Team = app.models.Team;
const existingId = '123';
const existingData = {
externalId: existingId,
botId: 'b123'
};
t.beforeEach(() => {
return Team.create(existingData).then(() => stubCreate());
});
t.test('crupdate', t => {
t = tp(t);
const newId = 'not 123'
const newData = {
externalId: newId,
whatever: 'value'
};
const newResult = Team.crupdate({
externalId: newId
}, newData);
const existingResult = Team.crupdate({
externalId: existingId
}, existingData);
return Promise.all([
t.equal(newResult, newData, 'Creates new Team when the external ID is different'),
t.match(existingResult, existingTeam, 'Finds existing Team when the external ID exists')
]);
}).then(() => {
process.exit();
}).catch(t.threw);
function stubCreate() {
Team.create = data => Promise.resolve(data);
}