Develop Reference

Execute promise or await with generated string variable

I am building a mongoose query and storing it in a variable call query. The code below shows it
let query = "Product.find(match)";
if (requestObject.query.sortBy) {
query = query.concat(".", "sort(sort)");
const parts = requestObject.query.sortBy.split(":");
sort[parts[0]] = parts[1] === "desc" ? -1 : 1;
}
if (requestObject.query.fields) {
query = query.concat(".", "select(fields)");
const fields = requestObject.query.fields.split(",").join(" ");
const items = await Product.find(match).sort(sort).select(fields); //.populate("category").exec();
/**const items = await Product.find(match).sort(sort).select("-__v"); //.populate("category").exec();**/
}
I am facing an issue when attempting to run a mongoose query that I have generated and stored in a string. When I run it in post man, the response is 200 but no data is returned. Below is a console.log(query) on line 2
what I hope to achieve is to have await or create a new promise execute the content id query variable like shown below
const items = new Promise((resolve) => resolve(query)); //.populate("category").exec();
items
? responseObject.status(200).json(items)
: responseObject
.status(400)
.json({ message: "Could not find products, please try again" });
I will appreciate it very much that and also if you can give me a better way of doing it, I will love that

This doesn't really make sense. You are building a string, not a query. You can't do anything with that string. (You could eval it, but you really shouldn't). Instead, build a query object!
let query = Product.find(match);
if (requestObject.query.sortBy) {
const [field, dir] = requestObject.query.sortBy.split(":");
const sort = {};
sort[field] = dir === "desc" ? -1 : 1;
query = query.sort(sort);
}
if (requestObject.query.fields) {
const fields = requestObject.query.fields.split(",");
query = query.select(fields);
}
//query.populate("category")
const items = await query.exec();
if (items) {
responseObject.status(200).json(items)
} else {
responseObject.status(400).json({ message: "Could not find products, please try again" });
}
If you really want to get that string for something (e.g. debugging), build it separately from the query:
let query = Product.find(match);
let queryStr = 'Product.find(match)';
if (requestObject.query.sortBy) {
const [field, dir] = requestObject.query.sortBy.split(":");
const sort = {[field]: dir === "desc" ? -1 : 1};
query = query.sort(sort);
queryStr += `.sort(${JSON.stringify(sort)})`;
}
if (requestObject.query.fields) {
const fields = requestObject.query.fields.split(",");
query = query.select(fields);
queryStr += `.select(${JSON.stringify(fields)})`;
}
//query.populate("category")
//queryStr += `.populate("category")`;
console.log(queryStr);
const items = await query.exec();
…

Wait for all Firebase data query requests before executing code

I am trying to fetch data from different collections in my cloud Firestore database in advance before I process them and apply them to batch, I created two async functions, one to capture the data and another to execute certain code only after all data is collected, I didn't want the code executing and creating errors before the data is fetched when i try to access the matchesObject after the async function to collect data is finished, it keeps saying "it cannot access a property matchStatus of undefined", i thought took care of that with async and await? could anyone shed some light as to why it is undefined one moment
axios.request(options).then(function(response) {
console.log('Total matches count :' + response.data.matches.length);
const data = response.data;
var matchesSnapshot;
var marketsSnapshot;
var tradesSnapshot;
var betsSnapshot;
matchesObject = {};
marketsObject = {};
tradesObject = {};
betsObject = {};
start();
async function checkDatabase() {
matchesSnapshot = await db.collection('matches').get();
matchesSnapshot.forEach(doc => {
matchesObject[doc.id] = doc.data();
console.log('matches object: ' + doc.id.toString())
});
marketsSnapshot = await db.collection('markets').get();
marketsSnapshot.forEach(doc2 => {
marketsObject[doc2.id] = doc2.data();
console.log('markets object: ' + doc2.id.toString())
});
tradesSnapshot = await db.collection('trades').get();
tradesSnapshot.forEach(doc3 => {
tradesObject[doc3.id] = doc3.data();
console.log('trades object: ' + doc3.id.toString())
});
betsSnapshot = await db.collection('bets').get();
betsSnapshot.forEach(doc4 => {
betsObject[doc4.id] = doc4.data();
console.log('bets object: ' + doc4.id.toString())
});
}
async function start() {
await checkDatabase();
// this is the part which is undefined, it keeps saying it cant access property matchStatus of undefined
console.log('here is matches object ' + matchesObject['302283']['matchStatus']);
if (Object.keys(matchesObject).length != 0) {
for (let bets of Object.keys(betsObject)) {
if (matchesObject[betsObject[bets]['tradeMatchId']]['matchStatus'] == 'IN_PLAY' && betsObject[bets]['matched'] == false) {
var sfRef = db.collection('users').doc(betsObject[bets]['user']);
batch11.set(sfRef, {
accountBalance: admin.firestore.FieldValue + parseFloat(betsObject[bets]['stake']),
}, {
merge: true
});
var sfRef = db.collection('bets').doc(bets);
batch12.set(sfRef, {
tradeCancelled: true,
}, {
merge: true
});
}
}
}
});

There are too many smaller issues in the current code to try to debug them one-by-one, so this refactor introduces various tests against your data. It currently won't make any changes to your database and is meant to be a replacement for your start() function.
One of the main differences against your current code is that it doesn't unnecessarily download 4 collections worth of documents (two of them aren't even used in the code you've included).
Steps
First, it will get all the bet documents that have matched == false. From these documents, it will check if they have any syntax errors and report them to the console. For each valid bet document, the ID of it's linked match document will be grabbed so we can then fetch all the match documents we actually need. Then we queue up the changes to the user's balance and the bet's document. Finally we report about any changes to be done and commit them (once you uncomment the line).
Code
Note: fetchDocumentById() is defined in this gist. Its a helper function to allow someCollectionRef.where(FieldPath.documentId(), 'in', arrayOfIds) to take more than 10 IDs at once.
async function applyBalanceChanges() {
const betsCollectionRef = db.collection('bets');
const matchesCollectionRef = db.collection('matches');
const usersCollectionRef = db.collection('users');
const betDataMap = {}; // Record<string, BetData>
await betsCollectionRef
.where('matched', '==', false)
.get()
.then((betsSnapshot) => {
betsSnapshot.forEach(betDoc => {
betDataMap[betDoc.id] = betDoc.data();
});
});
const matchDataMap = {}; // Record<string, MatchData | undefined>
// betIdList contains all IDs that will be processed
const betIdList = Object.keys(betDataMap).filter(betId => {
const betData = betDataMap[betId];
if (!betData) {
console.log(`WARN: Skipped Bet #${betId} because it was falsy (actual value: ${betData})`);
return false;
}
const matchId = betData.tradeMatchId;
if (!matchId) {
console.log(`WARN: Skipped Bet #${betId} because it had a falsy match ID (actual value: ${matchId})`);
return false;
}
if (!betData.user) {
console.log(`WARN: Skipped Bet #${betId} because it had a falsy user ID (actual value: ${userId})`);
return false;
}
const stakeAsNumber = Number(betData.stake); // not using parseFloat as it's too lax
if (isNaN(stakeAsNumber)) {
console.log(`WARN: Skipped Bet #${betId} because it had an invalid stake value (original NaN value: ${betData.stake})`);
return false;
}
matchDataMap[matchId] = undefined; // using undefined because its the result of `doc.data()` when the document doesn't exist
return true;
});
await fetchDocumentsById(
matchesCollectionRef,
Object.keys(matchIdMap),
(matchDoc) => matchDataMap[matchDoc.id] = matchDoc.data()
);
const batch = db.batch();
const queuedUpdates = 0;
betIdList.forEach(betId => {
const betData = betDataMap[betId];
const matchData = matchDataMap[betData.tradeMatchId];
if (matchData === undefined) {
console.log(`WARN: Skipped /bets/${betId}, because it's linked match doesn't exist!`);
continue;
}
if (matchData.matchStatus !== 'IN_PLAY') {
console.log(`INFO: Skipped /bets/${betId}, because it's linked match status is not "IN_PLAY" (actual value: ${matchData.matchStatus})`);
continue;
}
const betRef = betsCollectionRef.doc(betId);
const betUserRef = usersCollectionRef.doc(betData.user);
batch.update(betUserRef, { accountBalance: admin.firestore.FieldValue.increment(Number(betData.stake)) });
batch.update(betRef, { tradeCancelled: true });
queuedUpdates += 2; // for logging
});
console.log(`INFO: Batch currently has ${queuedUpdates} queued`);
// only uncomment when you are ready to make changes
// batch.commit();
}
Usage:
axios.request(options)
.then(function(response) {
const data = response.data;
console.log('INFO: Total matches count from API:' + data.matches.length);
return applyBalanceChanges();
}

MongoDB & Unable to set value depending on variable name

Coming across something i thought would have worked, but does not.
I have the following function that takes an input and needs to update one value in the mongodb.
const updateSkillXP = (data) =>{
//data = { username:username, sk:sk, xp:100 }
const collection = db.collection('player');
let q = {username:data.username}
//craft a key depending on what skill code comes through.
let s = "skills."+data.sk;
u = {$set: {s : data.xp}}
return collection.updateOne(q,u,(err,res) =>{
if(err) console.log(err);
})
}
The MongoDB document looks as follows
player = {
x:0,
y:0,
username:"foo",
skills : { //I need one of the following to update.
atk:0,
str:0,
def:0,
hp:0
}
}
When I executed the above, it added 'S' Property, but i was expecting to change the value of say 'atk' to what ever xp came through?

Answer:
JavaScript set object key by variable
const updateSkillXP = (data) =>{
//data = { username:username, sk:sk, xp:100 }
const collection = db.collection('player');
let q = {username:data.username}
let s = "skills."+data.sk;
let obj = {};
obj[s] = data.xp;
u = {$set: obj}
return collection.updateOne(q,u,(err,res) =>{
if(err) console.log(err);
})
}

How does one parent a channel to a category with a discord bot?

Basically there is no errors in the output but at the same time it's not doing what I'm trying to achieve.
Ive been tinkering with the script for 5 hours straight mixing up line positioning and now I got it to where it gives me the promise (my initial issue) but I cant parent the channel.
I've tried discord.js server and site, youtube, 2 other sites i forgot the name of but i cant crack it.
function setup(arguments, message){
var server = message.guild;
var name = message.author.username;
let searchquery = arguments.join("")
let cat = server.createChannel("Important", "category");
async function Channelmaker(Sent, obj){
try {
let chan = await server.createChannel(Sent, "Text");
//console.log(obj);
return chan
} catch(prom){
var chan2 = await server.createChannel(Sent, "Text");
return new Promise(resolve => {
var chan2 = server.createChannel(Sent, "Text", parent = obj);
resolve(chan2)
});
}
}
var holding
var chan = Channelmaker("⚖️ rules ⚖️", cat).then(value => {
console.log(value)
holding = value
value.parentID = cat
chan.setParent(cat.Id)
}).catch(error => {
// s
});
console.log("holding")
console.log(holding)
}
The category is not the parent of the "⚖️ rules ⚖️" channel that is created which is the opposite of what I'm trying to achieve

In Guild.createChannel(), use the options parameter including ChannelData, like so:
await server.createChannel(Sent, {
// You can omit the 'type' property; it's 'text' by default.
parent: obj
});

Convert a text from text file to array with fs [node js]

I have a txt file contains:
{"date":"2013/06/26","statement":"insert","nombre":1}
{"date":"2013/06/26","statement":"insert","nombre":1}
{"date":"2013/06/26","statement":"select","nombre":4}
how I can convert the contents of the text file as array such as:
statement = [
{"date":"2013/06/26","statement":"insert","nombre":1},
{"date":"2013/06/26","statement":"insert","nombre":1},
{"date":"2013/06/26","statement":"select","nombre":4}, ];
I use the fs module node js. Thanks
Sorry
I will explain more detailed:
I have an array :
st = [
{"date":"2013/06/26","statement":"insert","nombre":1},
{"date":"2013/06/26","statement":"insert","nombre":5},
{"date":"2013/06/26","statement":"select","nombre":4},
];
if I use this code :
var arr = new LINQ(st)
.OrderBy(function(x) {return x.nombre;})
.Select(function(x) {return x.statement;})
.ToArray();
I get the result I want.
insert select insert
but the problem my data is in a text file.
any suggestion and thanks again.

There is no reason for not to do your file parser yourself. This will work on any size of a file:
var fs = require('fs');
var fileStream = fs.createReadStream('file.txt');
var data = "";
fileStream.on('readable', function() {
//this functions reads chunks of data and emits newLine event when \n is found
data += fileStream.read();
while( data.indexOf('\n') >= 0 ){
fileStream.emit('newLine', data.substring(0,data.indexOf('\n')));
data = data.substring(data.indexOf('\n')+1);
}
});
fileStream.on('end', function() {
//this functions sends to newLine event the last chunk of data and tells it
//that the file has ended
fileStream.emit('newLine', data , true);
});
var statement = [];
fileStream.on('newLine',function(line_of_text, end_of_file){
//this is the code where you handle each line
// line_of_text = string which contains one line
// end_of_file = true if the end of file has been reached
statement.push( JSON.parse(line_of_text) );
if(end_of_file){
console.dir(statement);
//here you have your statement object ready
}
});

If it's a small file, you might get away with something like this:
// specifying the encoding means you don't have to do `.toString()`
var arrayOfThings = fs.readFileSync("./file", "utf8").trim().split(/[\r\n]+/g).map(function(line) {
// this try/catch will make it so we just return null
// for any lines that don't parse successfully, instead
// of throwing an error.
try {
return JSON.parse(line);
} catch (e) {
return null;
}
// this .filter() removes anything that didn't parse correctly
}).filter(function(object) {
return !!object;
});
If it's larger, you might want to consider reading it in line-by-line using any one of the many modules on npm for consuming lines from a stream.
Wanna see how to do it with streams? Let's see how we do it with streams. This isn't a practical example, but it's fun anyway!
var stream = require("stream"),
fs = require("fs");
var LineReader = function LineReader(options) {
options = options || {};
options.objectMode = true;
stream.Transform.call(this, options);
this._buffer = "";
};
LineReader.prototype = Object.create(stream.Transform.prototype, {constructor: {value: LineReader}});
LineReader.prototype._transform = function _transform(input, encoding, done) {
if (Buffer.isBuffer(input)) {
input = input.toString("utf8");
}
this._buffer += input;
var lines = this._buffer.split(/[\r\n]+/);
this._buffer = lines.pop();
for (var i=0;i<lines.length;++i) {
this.push(lines[i]);
}
return done();
};
LineReader.prototype._flush = function _flush(done) {
if (this._buffer.length) {
this.push(this._buffer);
}
return done();
};
var JSONParser = function JSONParser(options) {
options = options || {};
options.objectMode = true;
stream.Transform.call(this, options);
};
JSONParser.prototype = Object.create(stream.Transform.prototype, {constructor: {value: JSONParser}});
JSONParser.prototype._transform = function _transform(input, encoding, done) {
try {
input = JSON.parse(input);
} catch (e) {
return done(e);
}
this.push(input);
return done();
};
var Collector = function Collector(options) {
options = options || {};
options.objectMode = true;
stream.Transform.call(this, options);
this._entries = [];
};
Collector.prototype = Object.create(stream.Transform.prototype, {constructor: {value: Collector}});
Collector.prototype._transform = function _transform(input, encoding, done) {
this._entries.push(input);
return done();
};
Collector.prototype._flush = function _flush(done) {
this.push(this._entries);
return done();
};
fs.createReadStream("./file").pipe(new LineReader()).pipe(new JSONParser()).pipe(new Collector()).on("readable", function() {
var results = this.read();
console.log(results);
});

fs.readFileSync("myfile.txt").toString().split(/[\r\n]/)
This gets your each line as a string
You can then use UnderscoreJS or your own for loop to apply the JSON.parse("your json string") method to each element of the array.

var arr = fs.readFileSync('mytxtfile', 'utf-8').split('\n')
I think this is the simplest way of creating an array from your text file