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JavaScript problem with import, weird error

I have some code using library:
import { generateKeyPair } from 'jose/util/generate_key_pair'
async function funkcja () {
const {publicKey, privateKey} = await generateKeyPair('PS256')
console.log(publicKey)
console.log(privateKey)
}
funkcja()
and while trying to node it i get following error:
ubuntu#ubuntu-VirtualBox:~/Desktop/js$ node hello.js
/home/ubuntu/Desktop/js/hello.js:1
import { generateKeyPair } from 'jose/util/generate_key_pair'
^
SyntaxError: Unexpected token {
at Module._compile (internal/modules/cjs/loader.js:723:23)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
at Module.load (internal/modules/cjs/loader.js:653:32)
at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
at Function.Module._load (internal/modules/cjs/loader.js:585:3)
at Function.Module.runMain (internal/modules/cjs/loader.js:831:12)
at startup (internal/bootstrap/node.js:283:19)
at bootstrapNodeJSCore (internal/bootstrap/node.js:623:3)
I have no idea why this is happening, my friend is using exact same library and same code and on his computer it's working fine. (path to the library is correct) The only differennce is that he has node v12 and i have node v10.

Try this one
const { generateKeyPair } = require('jose/util/generate_key_pair');
Don't forget to use module.exports in generate_key_pair js file

How i read it in Update on ES6 Modules in Node.js the import of variables via curly brackets seems to be not supported in node.js.
it will simply not be possible to use the syntax:
import {foo, bar} from 'foobar';
But this would be possible:
import foobar from 'foobar';
console.log(foobar.foo(), foobar.bar());
So if generateKeyPair is a variable or function from 'jose/util/generate_key_pair' it should be:
import generate_key_pair from 'jose/util/generate_key_pair'
async function funkcja () {
const {publicKey, privateKey} = await generate_key_pair.generateKeyPair('PS256')
console.log(publicKey)
console.log(privateKey)
}
funkcja()

unable to call a local module from an application file in node.js

I am beginner in node.js.
I am trying to call a very basic addition module saved in C:\wks\guru99 with file name: Node_03_addition.js. The calling application is also saved in the same location with the name: app.js
Addition Module:
var exports = module.exports = {};
exports.addNumber=function(a,b)
{
return a+b;
};
Application File:
var Addition = require('/.Node_03_addition.js');
console.log(Addition.addNumber(1,2));
when I run the application in cmd using node app.js
I am receiving the error that Module is not found. Can someone please help me with where I am going wrong here.
c:\wks\guru99>node app.js
internal/modules/cjs/loader.js:969
throw err;
^
Error: Cannot find module '/.Node_03_addition.js'
Require stack:
- c:\wks\guru99\app.js
[90m at Function.Module._resolveFilename (internal/modules/cjs/loader.js:966:15)[39m
[90m at Function.Module._load (internal/modules/cjs/loader.js:842:27)[39m
[90m at Module.require (internal/modules/cjs/loader.js:1026:19)[39m
[90m at require (internal/modules/cjs/helpers.js:72:18)[39m
at Object.<anonymous> (c:\wks\guru99\app.js:1:16)
[90m at Module._compile (internal/modules/cjs/loader.js:1138:30)[39m
[90m at Object.Module._extensions..js (internal/modules/cjs/loader.js:1158:10)[39m
[90m at Module.load (internal/modules/cjs/loader.js:986:32)[39m
[90m at Function.Module._load (internal/modules/cjs/loader.js:879:14)[39m
[90m at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)[39m {
code: [32m'MODULE_NOT_FOUND'[39m,
requireStack: [ [32m'c:\\wks\\guru99\\app.js'[39m ]
}

SUGGESTION
// Node_03_addition.js
// Declare your function
const addNumber = function(a,b) {
return a + b;
};
// Export your function
module.exports = {
addNumber
};
// Application-File.js
// Import your module
const Addition = require('./Node_03_addition');
// Use it
console.log(Addition.addNumber(1,2)); // 3

Addition Module:
var exports = module.exports = {};
exports.addNumber=function(a,b)
{
return a+b;
};
Application File:
var Addition = require('./Node_03_addition.js');
console.log(Addition.addNumber(1,2));

mocha testing Angular (typescript) app that uses OpenLayers 6 fails with 'turf mocha "syntaxError: Unexpected token {"'

I solved this during the writing of the question and have provided my answer below since it was a bit tricky to work out. I am happy to hear any better or alternative answers.
I have an Angular OpenLayers 6 geomapping app. Being Angular I use Typescript and it transpiles and runs fine. And also being Angular it uses ng test to do the testing. All tests run fine.
However I use mocha + chai for testing in the IDE (IntelliJ) since I don't require UI testing for the mathematical work I'm currently performing (ng test runs the UI tests if and when I need that. But in the IDE I select the tests to run). Testing this way worked fine until I added a new test that creates a new instance of a class that imports GeoJSON:
import GeoJSON from 'ol/format/GeoJSON';
That test fails (in mocha) with:
/home/smx9b6/dev/ng-eow/node_modules/ol/format/GeoJSON.js:17
import { assert } from '../asserts.js';
^
SyntaxError: Unexpected token {
Looking at the GeoJSON.js file it seems to have UMD module format (i think this is UMD):
/**
* #module ol/format/GeoJSON
*/
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
import { assert } from '../asserts.js';
import Feature from '../Feature.js';
var GeoJSON = /** #class */ (function (_super) {
__extends(GeoJSON, _super);
/**
* #param {Options=} opt_options Options.
*/
function GeoJSON(opt_options) {
...
}
GeoJSON.prototype.writeGeometryObject = function (geometry, opt_options) {
return writeGeometry(geometry, this.adaptOptions(opt_options));
};
return GeoJSON;
}(JSONFeature));
And others, such as turf.js use the ES6 module format. eg. line-to-polygon:
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
var bbox_1 = require("#turf/bbox");
var invariant_1 = require("#turf/invariant");
var helpers_1 = require("#turf/helpers");
...
function lineToPolygon(lines, options) {
if (options === void 0) { options = {}; }
...
}
...
exports.default = lineToPolygon;
Mocha can't deal with this but Angular can - I don't know why. I run mocha with (as reported by IntelliJ when running the test - full paths removed):
node node_modules/mocha/bin/_mocha --require ts-node/register --ui bdd --reporter mochaIntellijReporter.js
src/app/geometry-ops.spec.ts --grep "^geometry-ops centroid "
I have commonjs set as the module type:
{
"extends": "./tsconfig.json",
"compilerOptions": {
"outDir": "./out-tsc/app",
"types": [],
"resolveJsonModule": true,
"module": "commonjs",
"esModuleInterop": true,
"allowSyntheticDefaultImports": true
},
...
}
The error in full is:
/home/smx9b6/dev/ng-eow/node_modules/ol/format/GeoJSON.js:17
import { assert } from '../asserts.js';
^
SyntaxError: Unexpected token {
at Module._compile (internal/modules/cjs/loader.js:723:23)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
at Module.load (internal/modules/cjs/loader.js:653:32)
at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
at Function.Module._load (internal/modules/cjs/loader.js:585:3)
at Module.require (internal/modules/cjs/loader.js:692:17)
at require (internal/modules/cjs/helpers.js:25:18)
at Object.<anonymous> (/home/smx9b6/dev/ng-eow/src/app/layers-geometries.ts:4:1)
at Module._compile (internal/modules/cjs/loader.js:778:30)
at Module.m._compile (/home/smx9b6/dev/ng-eow/node_modules/ts-node/src/index.ts:439:23)
at Module._extensions..js (internal/modules/cjs/loader.js:789:10)
at Object.require.extensions.(anonymous function) [as .ts] (/home/smx9b6/dev/ng-eow/node_modules/ts-node/src/index.ts:442:12)
at Module.load (internal/modules/cjs/loader.js:653:32)
at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
at Function.Module._load (internal/modules/cjs/loader.js:585:3)
at Module.require (internal/modules/cjs/loader.js:692:17)
at require (internal/modules/cjs/helpers.js:25:18)
at Object.<anonymous> (/home/smx9b6/dev/ng-eow/src/app/geometry-ops.spec.ts:13:1)
at Module._compile (internal/modules/cjs/loader.js:778:30)
at Module.m._compile (/home/smx9b6/dev/ng-eow/node_modules/ts-node/src/index.ts:439:23)
at Module._extensions..js (internal/modules/cjs/loader.js:789:10)
at Object.require.extensions.(anonymous function) [as .ts] (/home/smx9b6/dev/ng-eow/node_modules/ts-node/src/index.ts:442:12)
at Module.load (internal/modules/cjs/loader.js:653:32)
at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
at Function.Module._load (internal/modules/cjs/loader.js:585:3)
at Module.require (internal/modules/cjs/loader.js:692:17)
at require (internal/modules/cjs/helpers.js:25:18)
at /home/smx9b6/dev/ng-eow/node_modules/mocha/lib/mocha.js:334:36
at Array.forEach (<anonymous>)
at Mocha.loadFiles (/home/smx9b6/dev/ng-eow/node_modules/mocha/lib/mocha.js:331:14)
at Mocha.run (/home/smx9b6/dev/ng-eow/node_modules/mocha/lib/mocha.js:809:10)
at Object.exports.singleRun (/home/smx9b6/dev/ng-eow/node_modules/mocha/lib/cli/run-helpers.js:108:16)
at exports.runMocha (/home/smx9b6/dev/ng-eow/node_modules/mocha/lib/cli/run-helpers.js:142:13)
at Object.exports.handler.argv [as handler] (/home/smx9b6/dev/ng-eow/node_modules/mocha/lib/cli/run.js:292:3)
at Object.runCommand (/home/smx9b6/dev/ng-eow/node_modules/mocha/node_modules/yargs/lib/command.js:242:26)
at Object.parseArgs [as _parseArgs] (/home/smx9b6/dev/ng-eow/node_modules/mocha/node_modules/yargs/yargs.js:1087:28)
at Object.parse (/home/smx9b6/dev/ng-eow/node_modules/mocha/node_modules/yargs/yargs.js:566:25)
at Object.exports.main (/home/smx9b6/dev/ng-eow/node_modules/mocha/lib/cli/cli.js:68:6)
at Object.<anonymous> (/home/smx9b6/dev/ng-eow/node_modules/mocha/bin/_mocha:10:23)
at Module._compile (internal/modules/cjs/loader.js:778:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
at Module.load (internal/modules/cjs/loader.js:653:32)
at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
at Function.Module._load (internal/modules/cjs/loader.js:585:3)
at Function.Module.runMain (internal/modules/cjs/loader.js:831:12)
at startup (internal/bootstrap/node.js:283:19)
at bootstrapNodeJSCore (internal/bootstrap/node.js:622:3)
I worked out and provide an answer below. However I would still like to hear any feedback on this. Such as should OpenLayers change their module format? (I'm still getting my head around all the different module formats).

The answer is to add --require esm --require jsdom-global/register to the node / mocha call.
The esm is to specify ES6 as the module format and jsdom-global is to define the DOM in non-browser environments (specifically to define document).
The full command is:
node node_modules/mocha/bin/_mocha --ui bdd \
--require ts-node/register \
--require esm \
--require jsdom-global/register \
--reporter landing \
src/app/geometry-ops.spec.ts --grep "^geometry-ops centroid "
(I added spaces in the command since it irks me when I have to scroll right to see such things).
I am happy to hear any better or alternative answers.

NFC Error in nodejs

I was about to make a program that reads NFC cards via NFC reader.
when I execute my program i get the following errros...
/home/dotmark/Desktop/nfc2/node_modules/bindings/bindings.js:83
throw e
^
Error: libnfc.so.5: cannot open shared object file: No such file or directory
at Object.Module._extensions..node (module.js:598:18)
at Module.load (module.js:488:32)
at tryModuleLoad (module.js:447:12)
at Function.Module._load (module.js:439:3)
at Module.require (module.js:498:17)
at require (internal/module.js:20:19)
at bindings (/home/dotmark/Desktop/nfc2/node_modules/bindings/bindings.js:76:44)
at Object.<anonymous> (/home/dotmark/Desktop/nfc2/node_modules/nfc/index.js:1:95)
at Module._compile (module.js:571:32)
at Object.Module._extensions..js (module.js:580:10)
My script for loading nfc libraries is as follows...
var nfc = require('nfc').nfc
, util = require('util')
;
console.log('nfc.version(): ' + util.inspect(nfc.version(), { depth: null }));
// { name: 'libfnc', version: '1.7.0' }
console.log('nfc.scan(): ' + util.inspect(nfc.scan(), { depth: null }));
Any help would be really great..

JavaScript Exporting a class definition [duplicate]

This question already has answers here:
Destructuring in Node.JS
(3 answers)
Closed 7 years ago.
Can I export class definition in JavaScript? For example,
in file "HelloWorld.js":
'use strict';
class HelloWorld {
constructor(msg = 'Hello World~') {
this.message = msg;
}
sayHi() {
console.log(this.message);
}
}
module.exports = HelloWorld;
Then in "index.js"
'use strict';
var HelloWorld = require('HelloWorld');
var myObj = new HelloWorld;
myObj.sayHi();
if I do "node index.js", then I got the error below:
constructor(msg = 'Hello World~') {
^
SyntaxError: Unexpected token =
at exports.runInThisContext (vm.js:53:16)
at Module._compile (module.js:387:25)
at Object.Module._extensions..js (module.js:422:10)
at Module.load (module.js:357:32)
at Function.Module._load (module.js:314:12)
at Module.require (module.js:367:17)
at require (internal/module.js:16:19)
at Object.<anonymous> (/data/users/soltiho/fbsource/fbcode/video_templates/test_env/index.js:3:18)
at Module._compile (module.js:413:34)
at Object.Module._extensions..js (module.js:422:10)
my node is v5.5.0

Node doesn't support destructuring (yet), and using destructuring would be wrong anyways. There is nothing special about importing/exporting a class. Import it like any other module:
var myValue = require('myVModule');