Develop Reference

Error while using db.collection() in react project

Error:
firebase_compat_app__WEBPACK_IMPORTED_MODULE_0__.default.storage is not a function
import React, { useEffect } from "react";
import styled from "styled-components";
import ImageSlider from "./ImageSlider";
import Movies from "./Movies";
import Viewers from "./Viewers";
import Footer from "./Footer";
import db from "../firebase";
const Home = () => {
useEffect(() => {
db.collection("movies").onSnapshot((snapshot) => {
console.log(snapshot);
});
}, []);
};
I don't understand why this error occurred.

The error message "firebase_compat_app__WEBPACK_IMPORTED_MODULE_0__.default.storage is not a function" suggests that the "storage" property is not a function on the default export of the "firebase_compat_app" module. This means that the code is trying to access the "storage" property as if it were a function, but it is not.
This error might occur if the import of 'firebase' library is not done properly in the code. Make sure that you have imported 'firebase' library correctly and also it is initialized with the correct configuration.
Also, the error might occur if you are trying to use the 'storage' module but it is not included in the import statement or not enabled in the firebase project.
It is also possible that you are trying to use the storage module in an unsupported way with the version of the firebase library that you have installed.

Uncaught SyntaxError: The requested module '/node_modules/.vite/vue.js?v=31b05063' does not provide an export named 'default'

I don't know how to solve this problem.
When I started project vue3.js , console show me this error.
This import in pinia store.
I tryied change first line with import to
"import Vue from 'vue';" (without curcy braces), but error don't disappear.
import { Vue } from 'vue';
import { defineStore } from 'pinia';
import moment from 'moment';
import _ from 'lodash';
import router from '#/router';

if you are using latest version of vue , vue3
this code
import { Vue } from 'vue';
is no longer global instance

Attempted import error: 'ApiRequests' is not exported from './ApiRequests'

I am new in js and react,so:
i try to export js function:
App.js:
import React from 'react';
import logo from './logo.svg';
import './App.css';
import { render } from 'react-dom';
import { LazyLog } from 'react-lazylog';
import 'bootstrap/dist/css/bootstrap.min.css';
import { Dropdown } from 'react-bootstrap';
import {ApiRequests} from './ApiRequests'
var textConst="";
var lines=ApiRequests.GetMockLogLines();
textConst=lines;
And ApiRequests.js:
export function GetMockLogLines()
{
let logs=[""]
return logs;
}
So, when i compile js (o, my God) it breaks me:
Attempted import error: 'ApiRequests' is not exported from './ApiRequests'.
When i change it to :
import ApiRequests from './ApiRequests'
->
Attempted import error: './ApiRequests' does not contain a default export (imported as 'ApiRequests').
So, i just want to get function from another file. What i do wrong?
And what difference between {} and without it? (you can send me a link start to read,pls).

There is no function named Apirequests in your file. The function you are exporting is GetMockLogLines()
So your import should be
import {GetMockLogLines} from './ApiRequests'
As for the importing difference betweent {} and without the curly braces is how you are exporting your stuff from your file. There are two types of exports - Default export and named exports. One can have only one default export per file and it has to be imported without the curly braces.
You can read more here - https://medium.com/#etherealm/named-export-vs-default-export-in-es6-affb483a0910

you need to import GetMockLogLines directly as it is a named import.
change your code to the following.
import { GetMockLogLines } from './ApiRequests'
var lines=GetMockLogLines();

"Import in body of module; reorder to top import/first" Across Many Files

I have the same error as this answer, except instead of it just occurring in one file it is occurring in many; once I fix it for one file, another just pops up with the same error. I've seen this answer but whenever I run react-scripts start a node_modules folder is created in my src, so that solution isn't viable.
It would be too time consuming to have to fix every file that has this error every time I compile, so how can I get rid of this error? It seems to just be an eslint issue.

you will get this error if you declare variable in between your imports,
import React from 'react';
import axios from 'axios';
const URL = process.env.REACT_APP_API_BASE;
import demoXLXSFile from '../../assets/others/Demo.xlsx';
import './student.list.styles.scss';
declare variables after importing everything,
import React from 'react';
import axios from 'axios';
import demoXLXSFile from '../../assets/others/Demo.xlsx';
import './student.list.styles.scss';
const URL = process.env.REACT_APP_API_BASE;

I found this issue while I was using React.lazy in my existing project. I got this error Failed to compile. :- Import in body of module; reorder to top import/first (with create-react-app).
import React from 'react';
import SelectField from '../inputs/SelectField';
const Questions = React.lazy(() => import('./questions'))
import _ from 'lodash';
Solution:-
Only reorder the position i.e. put all import on top then react.lazy.
import React from 'react';
import SelectField from '../inputs/SelectField';
import _ from 'lodash';
const Questions = React.lazy(() => import('./questions'))

I got this same error when I added an extra semicolon ';' at the end of an import statement.
I suggest removing any extraneous semicolons. This should make the error go away.

Moving every import statement to the top of the file solves the issue.

Happened to me when I put require before import like this:
require('dotenv').config()
import React from 'react';
import ReactDOM from 'react-dom';
...
Solution: Put the require after the imports

If You are using Component Lazy loading then always put lazy load component import code below normal import code.
Correct Example
import First from './first'
const Second = React.lazy(()=>import("./Second))
Incorrect Example
const Second = React.lazy(()=>import("./Second))
import First from './first'

I came across this issue too. I found that you must import all ES6 modules at the top level of your JavaScript files."... the structure of ES6 modules is static, you can’t conditionally import or export things. That brings a variety of benefits.
This restriction is enforced syntactically by only allowing imports and exports at the top level of a module:"
From Dr. Axel Rauschmayer’s Exploring JS:

Wrong
1.
import React ,{useState ,useEffect} from 'react';
import './App.css';
import Post from './Post';
import db from "./firebase"
Right
2.
import React ,{useState ,useEffect} from 'react';
import './App.css';
import Post from './Post';
import db from "./firebase.js"
//this is code firebase.js
const db = firebaseApp.firestore();
const auth = firebase.auth();
const storage = firebase.storage();
export default {db,auth,storage};
When I change the firebase into firebase.js in Snippet 2.
My Error vanished

I had forgotten to add from.
Before:
import UpperBlock;
After:
import UpperBlock from "../components/dashboard/shared/UpperBlock";
Make sure you import well your component and then stop the server and restart it again. It worked for me.

I forgot to add {Component} after importing 'react' library to my project, this solved my issue.

Move all of your imports to the top of the file.
Even in case of a require (that is written in between import statements), this error will come.
e.g.
import 'some_module';
require('some_file');
import 'some_other_module');
This would result in an error.
You would want to do this instead:
import 'some_module';
import 'some_other_module');
require('some_file');

I was facing the same issue when I installed chat.js library in my reactJs project. I solved this issue by moving my chart.Js import to the index.js file
index.js file:
import React from "react";
import ReactDOM from "react-dom";
import { Chart as ChartJS, ArcElement, Tooltip, Legend } from "chart.js"; <--- imported
import "./index.css";
import App from "./App";
ChartJS.register(ArcElement, Tooltip, Legend); <---- imported

If you're experiencing this error in modern versions of react(current version 18.0.0) make sure you're making all your imports before the ReactDOM.createRoot declaration.
For example, I got the error with:
import App from "./App";
import reportWebVitals from "./reportWebVitals";
const root = ReactDOM.createRoot(document.getElementById("root"));
import { Provider } from "./context";
This will result in an error. Instead, import everything before the createRoot:
import App from "./App";
import reportWebVitals from "./reportWebVitals";
import { Provider } from "./context";
const root = ReactDOM.createRoot(document.getElementById("root"));
This will fix the error. Simple fix but it's easy to miss

If I put double Semicolon behind the importing statement than I got "error".you can see difference between two pictures in import './index.css'; is different
For Example :-
import React from 'react';
import ReactDOM from 'react-dom/client';
import './index.css';;
import 'tachyons';
import {robots} from "./Robots";
import reportWebVitals from './reportWebVitals';
import CardList from './CardList';

React JSX file giving error "Cannot read property 'createElement' of undefined"

I have a file test_stuff.js that I am running with npm test
It pretty much looks like this:
import { assert } from 'assert';
import { MyProvider } from '../src/index';
import { React } from 'react';
const myProvider = (
<MyProvider>
</MyProvider>
);
describe('Array', function() {
describe('#indexOf()', function() {
it('should return -1 when the value is not present', function() {
assert.equal(-1, [1,2,3].indexOf(4));
});
});
});
Unfortunately, I get the error
/Users/me/projects/myproj/test/test_stuff.js:11
var myProvider = _react.React.createElement(_index.MyProvider, null);
^
TypeError: Cannot read property 'createElement' of undefined
at Object.<anonymous> (/Users/me/projects/myproj/test/test_stuff.js:7:7)
What does that mean? I am importing React from 'react' successfully, so why would React be undefined? It is _react.React, whatever that means...

To import React do import React from 'react' You add brackets when the thing you are importing is not the default export in that module or file. In case of react, it's the default export.
This might apply to your other imports depending on how you defined them.

import React, { Component } from 'react'
This worked for me. I'm not sure why it fixed my version of this issue, though. So if you are someone who stumbled upon this problem and you use create-react-app as your starting boilerplate, this way of importing React will do the trick. (as of Oct '18, lol)

For those who are working ReactJS with TypeScript.
import * as React from 'react';

This error occured to me due to carelessness. It's actually
import React from 'react';
Brackets are for named exports such as this:
import React, { useState, useEffect } from 'react';

This issue occurred while importing React from react, I placed it inside curly brackets.
Please do this:
import React, {useState} from "react";
Instead of:
import {React, useState} from "react";

Trying to use destructor for importing the React object may cause you problems like this import {React} from 'react';.
This might be the cause of the error 90% of the time running this code above.
rather use:
import React from 'react';
And then you can access any member of the React class via:
React.

Change:
import { React } from 'react' to import React from 'react'
Because React is a default export and you don’t need curly braces for any default exports.

If in case you need to import multiple classes from 'react', you can have an alias for them except React. Something like,
import React, * as react from 'react';

React is exported by default in that module, no need {}.

I got this when trying to mock a component when unit testing but was not setting it up correctly
What I was doing that caused the error:
jest.mock("./SomeComponent", () => {
return <div>MockSomeComponent</div>
});
What I needed to do:
jest.mock("./SomeComponent", () => {
return () => <div>MockSomeComponent</div>
});

This error can be occured due to carelessness. Please add
import React from 'react'
It will be resolved after that