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I tried to get data using filter in nodejs and firestore when show me this error "Cannot read properties of undefined (reading '_internalPath')"

I tried to get data using filter in nodejs and firestore when show me this error in postman
"Cannot read properties of undefined (reading '_internalPath')"
my code
const getAllWords = async (req, res, next) => {
let categoryName = "fruits"
try {
const word = await firestore.collection('12words');
const data = await word.where({categoryName}).get();
const wordArray = [];
if(data.empty) {
res.status(404).send('No words12 found');
}else {
data.forEach(doc => {
const words = new Word12(
doc.id,
doc.data().name,
doc.data().categoryName,
);
wordArray.push(words);
});
res.send(wordArray);
}
} catch (error) {
res.status(400).send(error.message);
}
}

The .where() takes 3 parameters (fieldPath, opStr, value) but you are passing only 1 object. Try refactoring the code as shown below:
// replace fieldName with the field name in document
const data = await word.where("fieldName", "==", categoryName).get();

Unhandled Rejection (SyntaxError): Unexpected end of JSON input with Get request fetch

I am trying to do a MVC architecture tutorial from Codecademy's website: https://www.codecademy.com/article/mvc-architecture-for-full-stack-app
I finished the tutorial but when I run everything, I get this error:
It seems that what I'm returning is not valid JSON. So I think the problem is that the endpoint may be causing the error. But I'm not too sure. Here is the code where the error is triggered:
src/utils/index.js:
export const fetchExpenses = async (date) => {
const selectDate = new Date(date).getTime() || new Date().getTime();
const res = await fetch(`/api/expense/list/${selectDate}`);
console.log('result',res);
return res.json();
};
Here is the code from app.js in the "view" portion of my code:
useEffect(() => {
// update view from model w/ controller
fetchExpenses().then((res) => setExpenses(res));
}, []);
It seems the problem is the communication between the view and the controller. When I create an expense, it actually is updated in the database:
Any ideas why this error is happening?
Edit 1:
Here is the network response when I try to create a new expense in my application. So it seems that when I create a new expense, the fetchExpenses() is automatically called to display a list of current expenses.
this the raw response I get from fetchExpenses() :
Edit 2:
Here is what the header shows from the response:
The endpoint is causing the error, but I'm not sure why. Here is the endpoint:
export const createExpense = async (data) => {
const res = await fetch(`/api/expense/create`, {
method: 'POST',
body: data,
});
return resHandler(res, 201);
};
and here is resHandler() which createExpense() returns:
export const resHandler = async (res, status) => {
if (res.status === status) {
return null;
}
const data = await res.json();
if (data && data.emptyFields) {
return data.emptyFields;
}
return null;
};
Here is the code from the controller when an expense is created:
exports.create = (req, res) => {
const form = new formidable.IncomingForm();
form.keepExtensions = true;
form.parse(req, async (err, fields) => {
const { title, price, category, essential, created_at } = fields;
// check for all fields
if (fieldValidator(fields)) {
return res.status(400).json(fieldValidator(fields));
}
try {
const newExpense = await pool.query(
'INSERT INTO expenses (title, price, category, essential, created_at) VALUES ($1, $2, $3, $4, $5)',
[title, price, category, essential, created_at]
);
return res.status(201).send(`User added: ${newExpense.rows}`);
} catch (error) {
return res.status(400).json({
error,
});
}
});
};
Edit 3
Here is the route /api/expense/list/{dateTime}:
const express = require('express');
const router = express.Router();
const { create, expenseById,
read, update, remove, expenseByDate } = require('../controllers');
router.get('/expense/list/:expenseDate', expenseByDate, read);
module.exports = router;
And here is my controllers.js that deal with the route above:
exports.expenseByDate = async (req, res, next, date) => {
try {
const expenseQuery = await pool.query(
'SELECT * FROM expenses WHERE created_at BETWEEN $1 AND $2',
[
startOfDay(new Date(Number(date))).toISOString(),
endOfDay(new Date(Number(date))).toISOString(),
]
);
const expenseList = expenseQuery.rows;
req.expense =
expenseList.length > 0
? expenseList
: `No expenses were found on this date.`;
return next();
} catch (error) {
return res.status(400).json({
error,
});
}
};
exports.read = (req, res) => res.json(req.expense);

The reason you are getting an Unhandled Rejection (SyntaxError): Unexpected end of JSON input error is because your client app is expecting a JSON response and the express app /api/expense/list/{dateTime} route is not returning valid JSON.
The app is not returning valid JSON because the expenseByDate controller callback has an incorrect function signature so it is not getting called.
exports.expenseByDate = async (req, res, next, date) => <-- "date" is not a valid parameter.
This leads the read controller to return an undefined value to the json response.
exports.read = (req, res) => res.json(req.expense); <-- req.expense is undefined.
res.json(undefined) ultimately returns an empty response to the client which can't be parsed and thus an error is thrown.
Solution
You can fix this error by correcting the expenseByDate controller to have a valid function signature by removing the fourth method parameter. To access a route parameter you should use req.params.
exports.expenseByDate = async (req, res, next, date) => {
const date = req.params.expenseDate;
...
}

Javascript Access an an Object in an Array

I'm fetching data from MongoDB, and the response is coming through fine, however it appears to be wrapped in array when it comes out of the User.find() function.
For example, one response is:
[{"_id":"62fe3c888e2776ef3c1a010f","username":"Drago D Trial","password":"U2FsdGVkX1867hs26KL0KitTGhWnP9tdVX6AcmI5pWE=","fullname":"Drago DaTrial","firstname":"","surname":"","email":"drago#hotmail.com","position":"QA Tester","userImage":"","locationCity":"","country":"","role":"","company":"","emailAuthorised":true,"professionalBio":"","positionRecentTitle":"","positionRecentCompany":"","companyAuthorised":"","isAdmin":false,"createdAt":"2022-08-18T13:20:08.045Z","updatedAt":"2022-08-18T13:21:02.619Z","__v":0}]
I'm accessing this through an api like this:
router.get('/inviteToJoinTeam/:token/:email', async (req, res) => {
try {
//verify the token against DB
const userToken = (req.params.token)
const indivEmailAdd = (req.params.email)
// creating user auth
try{
const userDetails = await User.find({email: indivEmailAdd})
const indivIDAdd = await userDetails (!want to access the data here and just get ID)
res.send(indivIDAdd)
}catch{
console.log('failure')
}
} catch (e) {
res.send('This isnt working');
}
});
How would you access this and just get the _id field out?

If there is only one item in the array then - simply get the id property of the first item intthe returned array
const indivIDAdd = await userDetails[0]['_id'];
or using dot notation
const indivIDAdd = await userDetails[0]._id;
if there are multiple results then map over the results and get the id from each
const ids = await userDetails.map(user => user._id);

just use response[0]._id
Ps: Response is the array coming from the database

Try projection for the same it should work
const userDetails = await User.find({ email: indivEmailAdd }, { _id : 1 })
it will return array of ObjectId. if you need to get only one object then use findOne instead of find.

According to me you have 2 solutions :
Option 1 use findOne instead of find :
const userDetails = await User.findOne({email: indivEmailAdd});
Option 2 access array / object with basic js:
const usersDetails = await User.find({email: indivEmailAdd});
const userDetails = usersDetails.at(0)._id; // or
const userDetails = usersDetails[0]['_id'];

Send Map in express res.send

I'm working on a game with a friend and we need to send a Map with some stuff in it, but express only sends the user {} instead of the actual Map. The problem is at sending it and not the code itself, console.log'ging it does return the Map.
Code:
router.get("/list", async (req, res) => {
try {
const users = await userCollection.find();
accessedListEmbed(req);
let userData = new Map();
users.forEach((user) => userData.set(user.userName, user.status));
res.send(userData);
console.log(userData);
} catch (error) {
res.send("unknown");
}
});

Generally, you can only send serializable values over the network. Maps aren't serializable:
const map = new Map();
map.set('key', 'value');
console.log(JSON.stringify(map));
Either send an array of arrays that can be converted into a Map on the client side, or use another data structure, like a plain object. For example:
router.get("/list", async (req, res) => {
try {
const users = await userCollection.find();
accessedListEmbed(req);
const userDataArr = [];
users.forEach((user) => {
userDataArr.push([user.userName, user.status]);
});
res.json(userDataArr); // make sure to use .json
} catch (error) {
// send JSON in the case of an error too so it can be predictably parsed
res.json({ error: error.message });
}
});
Then on the client-side:
fetch(..)
.then(res => res.json())
.then((result) => {
if ('error' in result) {
// do something with result.error and return
}
const userDataMap = new Map(result);
// ...
Or something along those lines.

run synchronouse function in a promise

I am new to JS and async operations. In a router of nodeJS using express, I have aggregated some data from mongo using mongoose. The data is weather data collected from different sites every 15 minutes interval. I processed the data with mongoose aggregate pipeline to get hourly data and group by each site. But the data needs a further process to get periods where for example relative humidity over 90% and assign scores to each period so I wrote some synchronous functions that target each site (each geojson object).
Mongoose looks something like that:
module.exports.filteredData = function (collection, dateInput) {
return collection.aggregate([
{
$addFields :{
DateObj: {
$dateFromString: {
dateString: "$DateTime",
format: '%Y-%m-%d'
}
},
}
},
{
$addFields :{
NewDateTimes: {
$dateFromParts:{
'year': {$year: '$DateObj'},
'month':{$month: '$DateObj'},
'day':{$dayOfMonth: '$DateObj'},
'hour': {$toInt: "$Time"}
}
}
}
}
...
synchronouse functions:
const calcDSV = function(featuresJSON){
// featuresJSON
const SVscore = [];
const tuEval = featuresJSON.features.properties.TU90; // array
const obArr = featuresJSON.features.properties.OB; // array
const periodObj = getPeriods(tuEval);// get period position
const paramObj = getParams(periodObj, obArr); // get parameters
const periodDate = getPeriodDate(featuresJSON, periodObj);
const removeTime = periodDate.beginDate.map(x=>x.split('T')[0]);
let hourly = paramObj.hourCounts;
let avgTemps = paramObj.avgTemps;
for(let i = 0;i<hourly.length; i++){
let score = assignScore(avgTemps[i], hourly[i]);
SVscore.push(score);
}
// output sv score for date
const aggreScore = accumScore(removeTime, SVscore);
aggreScore.DSVdate = aggreScore.Date.map(x=>new Date(x));
featuresJSON.features.properties.periodSV = SVscore;
featuresJSON.features.properties.Periods = periodDate;
featuresJSON.features.properties.DSVscore = aggreScore;
return featuresJSON;
}
Now I am stuck on how to apply those function on each site return by the mongoose aggregate pipeline on a post request:
router.post('/form1', (req, res, next)=>{
const emdate = new Date(req.body.emdate);
const address = req.body.address;
const stationDataCursor = stationData.filteredData(instantData, emdate);
stationDataCursor.toArray((err, result)=>{
if(err){
res.status(400).send("An error occurred in Data aggregation")
};
res.json(result.map(x=>calcDSV.calcDSV(x)));
})
});
I tried in the callback:
stationDataCursor.toArray((err, result)=>{
if(err){
res.status(400).send("An error occurred in Data aggregation")
};
res.json(result.map(async (x)=>await calcDSV.calcDSV(x))));
})
and using then():
stationDataCursor.toArray().then((docArr)=>{
let newfeature = await docArr.map(async (x)=> await calcDSV.calcDSV(x))));
res.json(newfeature);
})
or make calcDSV() returns new promise
return new Promise((rej, res)=>{
resolve(featuresJSON);
})
I would expect to see all sites with a new feature added in the HTTP response output. But most of the time, I got ReferenceError: error is not defined.

I think I have figured it out:
after all, have to make all synchronous functions asynchronous by prepending async to those functions;
rewrite this part in the post router function, especially the array map part. I read from this. and in the map() gonna have try...catch... in it, otherwise it won't work.
await stationDataCursor.toArray().then(async (docArr)=>{
const newfeature = await Promise.all(docArr.map(async function(x){
try{
const feature = await calcDSV.calcDSV(x);
return feature
} catch(err){
console.log("Error happened!!! ", err);
}
}));
res.json(newfeature)
})
Hope it helps.