webpack function usage after bundling - javascript

I try to pack that https://www.npmjs.com/package/#jscad/dxf-deserializer library and use in browser.
Uage from node looks like
const deSerializer = require('#jscad/dxf-deserializer')
const rawData = fs.readFileSync('PATH/TO/file.dxf')
const jscadCode = deSerializer(rawData)
How should i use that now after linking bundle script?
I had tried
let objs = deserialize(fileText,'square10x10',{output: 'csg'})
and got
ReferenceError: deserialize is not defined
There is js test file works fine with node
const fs = require('fs')
const path = require('path')
const test = require('ava')
const { CSG, CAG } = require('#jscad/csg')
const { nearlyEqual } = require( '../../../test/helpers/nearlyEqual' )
const { deserialize } = require( '../index' )
const samples = path.resolve('../../node_modules/#jscad/sample-files')
//
// Test suite for DXF deserialization (import)
//
test('ASCII DXF from Bourke 3D Entities to Object Conversion', t => {
//const dxfPath = path.resolve(__dirname, '../../../../sample-files/dxf/bourke/3d-entities.dxf')
const dxfPath = path.resolve(samples, 'dxf/bourke/3d-entities.dxf')
t.deepEqual(true, fs.existsSync(dxfPath))
let dxf = fs.readFileSync(dxfPath, 'UTF8')
let objs = deserialize(dxf,'aaa',{output: 'objects'})
// expect one layer, containing 2 objects (CSG, and Line3D)
t.true(Array.isArray(objs))
t.is(objs.length,2)
})

Try Adding
node: {
fs: "empty"
}
fs module isn't defined in the browser.
Maybe that's what stopping deserialize from been created. With a try.

Related

How could I duplicate/copy file in an automatized way with JavaScript?

I have an gif file that is stored in a directory call assets on my computer. I would like to create X amount of duplicates and they should be stored in the same directory and each of them should have a different file name.
Example:
I in the assets directory is the gif file call 0.gif I would like to duplicate this gif file 10 times and The duplicates should be called 1.gif, 2.gif, 3.R and so on.
The simplest option is to use fs and using copyFile function available
const fs = require("fs");
const path = require("path");
let copyMultiple = (src, count) => {
let initCount = 0;
while (initCount < count) {
initCount++;// you can put this at bottom too acc to your needs
const newFileName = `${initCount}_${initCount}${path.extname(src)}`;
console.log(newFileName, "is new file name");
fs.copyFile(src, newFileName, (error) => {
// if errors comes
if (error) {
console.log(error);
}
});
}
};
copyMultiple("1.gif", 3);
Another elegant way of doing this is
const util = require("util");
const fs = require("fs");
const path = require("path");
const copyFilePromise = util.promisify(fs.copyFile);
function copyFiles(srcFile, destDir, destFileNames) {
return Promise.all(
destFileNames.map((file) => {
return copyFilePromise(srcFile, path.join(destDir, file));
})
);
}
const myDestinationFileNames = ["second.gif", "third.gif"];
const sourceFileName = "1.gif";
copyFiles(sourceFileName, "", myDestinationFileNames)
.then(() => {
console.log("Copying is Done");
})
.catch((err) => {
console.log("Got and Error", error);
});
Using this will also give upperhand of knowing when it is done.
You can read docs here
const fs = require("fs")
const filename = "index.js".split(".") //filename like 0.gif to gif
const times = 10 // number of times to duplicate
for(var int = 1; int < times; int++){
const newFilename = `${(parseInt(filename[0]) + init)}.${filename[1]}` //new filename like 0.gif to 1.gif
fs.copyFileSync(filename, newfilename)
}
use the write file and read file from the fs module and a simple for loop
not sure which framework you're on but fs.copyFile() is the standard way for node.js https://nodejs.org/api/fs.html#fscopyfilesrc-dest-mode-callback

how to extract password-protected zip in Node Js

const unzipper = require("unzipper");
const fs = require("fs-extra");
async function test() {
const file = "old.zip";
const password = "abc";
const directory = await unzipper.Open.file(file);
console.log("password", password);
const extracted = await directory.files[0].buffer(password);
fs.writeFileSync("extracted/", extracted);
}
test();
I have two files, old.zip and new.zip. The only difference is that when I created old zip using winrar, I checked legacy encryption. You can see the picture below.
My code works for old zip, but not new.zip. Is there any other way to extract the new.zip file?
edit: change title from using javascript => in Node js

Node.js require multiple files in the same folder

I'm building a discord bot with node.js for my server and I have a bunch of commands for the bot. Each command is in a different file so I have a lot of const cmd = require("../commands/cmd.js");
const kick = require("../commands/kick");
const info = require("../commands/info");
const cooldown = require("../commands/cooldown");
const help = require("../commands/help");
Is there a simpler way to do this?
Inside folder commands put a file called index.js.
Each time you implement new commands in new file, require that file in index.js and then add it to the exports of it. For example index.js would be:
const kick = require('./kick');
const info = require('./info');
module.exports = {
kick: kick,
info: info
}
And then from any folder you can require multiple commands in one line like this:
const { kick, info } = require('../commands');
Export an object from one file instead?
const kick = require("../commands/kick");
const info = require("../commands/info");
const cooldown = require("../commands/cooldown");
const help = require("../commands/help");
const commands = {
kick,
info,
...
}
module.exports = commands;
And then:
const commands = require('mycommands')
commands.kick()
Create index.js file inside the command folder and then you can export an object like this.
const kick = require("../commands/kick");
const info = require("../commands/info");
const cooldown = require("../commands/cooldown");
const help = require("../commands/help");
const command = {
kick,
info,
cooldown,
help
};
module.exports = command;
You can import and use it like this:
const {kick, info} = require('./commands');

Cost of importing in Javascript [duplicate]

So I'm planning to separate my functions into separate files and then import them into a single index.js which then becomes the main exporter. So I'm wondering if having something like var bcrypt = require('bcrypt') in several of my files be slower than just having it in one file.
Here's how I'm planning to group and export in index.js
const fs = require('fs');
const path = require('path')
const modules = {}
const files = fs.readdirSync(__dirname)
files.forEach(file => {
if (file === 'index.js') return
let temp = require(path.join(__dirname, file))
for (let key in temp) {
modules[key] = temp[key]
}
});
module.exports = modules
As an example of what I mean:
file1.js
var bcrypt = require("bcrypt");
module.exports.file1test = "hi"
file2.js
var bcrypt = require("bcrypt");
module.exports.file2test = "bye"
No, it does not. Whenever a module is required for the first time, the module's code runs, assigns something to its exports, and those exports are returned. Further requires of that module simply reference those exports again. The logic is similar to this:
const importModule = (() => {
const exports = {};
return (name) => {
if (!exports[name]) exports[name] = runModule(name);
return exports[name];
};
})();
So, multiple imports of the same module is no more expensive than referencing an object multiple times.

Nodejs - How to get the version of a dependency

Is there a way to get the version of an external dependency in JS code, without hardcoding it?
If you wanted to get the value of express you could do something like the following. You are looping over each folder in the node modules and adding the name and the version to an object.
const fs = require('fs');
const dirs = fs.readdirSync('node_modules');
const packages = {};
dirs.forEach(function(dir) {
const file = 'node_modules/' + dir + '/package.json';
const json = require(file);
const name = json.name;
const version = json.version;
packages[name] = name;
packages[version] = version;
});
console.log(packages['react-native']); // will log the version

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