bundle.js not getting created - node.js

I am trying to create simple webpack project using vs code.
It has two folders:
1.dist
2.src
i have app.js file in src folder and i need the bundle file to be created with the webpack command
for this i am using below command
webpack ./src/app.js ./dist/bundle.js
but this command is giving below error
ERROR in multi ./src/app.js ./dist/app.bundle.js
Module not found: Error: Can't resolve './dist/app.bundle.js' in 'D:\Webpack\WEBPACK-101'
# multi ./src/app.js ./dist/app.bundle.js
There is some minor thing which I am missing, it would be very helpful if anyone can figure it out what exactly I am missing?
Thanks in advance!!!

If you don't have a webpack.config.js file, you can rely on the default configuration for that, but you need to do some things before.
First, your "main" script has to be in: src/ and it should be named index.js
By default the output is always dist/.
So knowing that, you can run: webpack. And your bundle is going to be generated.
Or you could webpack --entry ./src/app.js --output ./dist/bundle.js

You will need to create webpack.config.js
const path = require('path');
module.exports = {
entry: './src/app.js',
output: {
filename: 'bundle.js',
path: path.resolve(__dirname, 'dist')
}
};
Update package.json
{
"name": "webpack-demo",
"version": "1.0.0",
"description": "",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
+ "build": "webpack"
},
.....
}
And Run
npm run build
More Details

First of all it is important that all data in fajl package.json will be entered through the command line/ terminal/gitshell...Than, on windows 10 I resolved the problem with typing in terminal next:
$ npm install typescript

Related

Generate stand alone js artifacts using Vite as side effect of another build

I'm using Vite (vite#3.1.8)
to build Typescript artifacts for an SPA "site" using SolidJS (solid-js#1.6.0).
here's my vite.config.ts
import { defineConfig, resolveBaseUrl } from 'vite'
import solidPlugin from 'vite-plugin-solid'
export default defineConfig({
plugins: [solidPlugin()],
server: {
port: 3000,
},
build: {
target: 'esnext',
outDir: '../htdocs',
rollupOptions: {
input: {
index: "./index.html",
dev: "./dev.html",
test: "./test.ts",
},
output: {
entryFileNames: `assets/[name].js`,
chunkFileNames: `assets/[name].js`,
assetFileNames: `assets/[name].[ext]`
}
},
},
});
Currently, it actually builds 2 html files (index.html and dev.html) and the artifacts needed to run those files. Its great. Couldn't be happier.
I would like to have the transpiler to also kick out test.js so that I can run it to do some sanity checking before deploying to production.
I'm hoping to do vite build, and then run node ../htdocs/assets/test.js (or something similar), and have it block the final deployment if any my sanity tests fail.
however, when I attempt to do this, I get an error when I run test.js, complaining about my use of import statements.
Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
setting my package type to module in package.json doesn't fix it. changing the test file to test.mjs doesnt fix it. I'm not really sure what to try next.
What I really wish it would do is do the whole "import" as part of transpiling, and make one self-contained test.js that just runs. It seems like that is what it does when it builds index.html and dev.html, why wont it do that for my ts file?
That should work. I just tried making a new repo with your vite.config.ts, one-line index.html, dev.html, and test.ts files, and vite, vite-plugin-solid, solid-js installed. In the end I got a ../htdocs/assets/test.js file.
You might also be interested in checking out Vitest which makes testing like this easier to do, and won't accidentally end up in your deployed htdocs.
The best solution I could find was to make a separate config file for building the tests.
import { defineConfig } from 'vite'
import solidPlugin from 'vite-plugin-solid'
export default defineConfig({
plugins: [solidPlugin()],
server: {
port: 3000,
},
build: {
target: 'esnext',
outDir: '../htdocs',
lib: {
entry: "./test-runner.ts",
name: "test-runner",
fileName: "test-runner"
},
rollupOptions: {
},
},
});
and then, update my package.json to make my test script compile and run the output from that alternative vite config.
"scripts": {
"start": "vite",
"dev": "vite",
"build": "vite build",
"serve": "vite preview",
"test": "vite build --config vite.config-tests.ts && node ../htdocs/test-runner.umd.js"
},

babelrc not sufficient to use with babel --watch

I have this .babelrc file:
{
"presets": ["env"],
"outDir":"target",
"include":[
"src/**/*.js"
],
"ignore": []
}
I run babel -w and I get this error message:
--watch requires --out-file or --out-dir. --watch requires filenames
do I need to specify more options at the command line or is there something I can add to my .babelrc file?
There is no way to configure this in your .babelrc. But you could add something like this to the scripts section of your package.json:
"scripts": {
"watch": "babel --watch src --out-dir dist"
}
Then you can just run npm run watch from the root of that project.
If you want to execute your project each time you compile, you can use babel-watch.

babel-preset-react-app not picking up environment variables

Failed to compile ./src/index.js Module build failed: Error: Using
babel-preset-react-app requires that you specify NODE_ENV or
BABEL_ENV environment variables. Valid values are "development",
"test", and "production". Instead, received: "undefined". (While
processing
preset:"C:\Users\mitch\OneDrive\Development\Git\react-seed\node_modules\babel-preset-react-app\index.js")
at Array.map (native)
I keep getting the above error no matter how many weird and wonderful ways I try to set either the environment or the environment variables since updating my react-app and I even get this on a fresh app created from the 'create-react-app' scripts - What am I clearly doing wrong?
I do it in my package.json:
{
"scripts": {
"build": "NODE_ENV=development babel src -d lib",
"build-prod": "NODE_ENV=production babel src -d lib"
}
}
Using babel-preset-react-app requires that you specify NODE_ENV or BABEL_ENV environment variables. Valid values are "development", "test", and "production". Instead, received: "development "
Ran into a similar problem and noticed that a space character messed things up with this configuration:
SET NODE_ENV=development && node server/bootstrap.js
//Changed to this:
SET NODE_ENV=development&&node server/bootstrap.js
{
"scripts": {
"build": "export NODE_ENV=development && babel src -d lib",
"build-prod": "export NODE_ENV=production && babel src -d lib"
}
}

Cannot find config module when running mocha but works when running nodemon

When I run my server:
from my package.json file:
"scripts": {
"start": "grunt & nodemon ./dist/server.js",
"test": "mocha"
},
from my server.coffee file:
config = require './config'
Everything works fine, but when I run my test I get the following error:
Error: Cannot find module './config'
Here is my folder structure:
The config is not loaded in test/users.coffee, it is loaded from the server.coffee file which is loaded into tests/users.coffee
server = require '../src/server/server'
The require path will be different from your test directory.
config = require './src/server/config'

Webpack --watch and launching nodemon?

Thanks to an excellent answer by #McMath I now have webpack compiling both my client and my server. I'm now on to trying to make webpack --watch be useful. Ideally I'd like to have it spawn something like nodemon for my server process when that bundle changes, and some flavor of browsersync for when my client changes.
I realize it's a bundler/loader and not really a task runner, but is there some way to accomplish this? A lack of google results seems to indicate I'm trying something new, but this must have been done already..
I can always have webpack package to another directory and use gulp to watch it/copy it/browsersync-ify it, but that seems like a hack.. Is there a better way?
Install the following dependencies:
npm install npm-run-all webpack nodemon
Configure your package.json file to something as seen below:
package.json
{
...
"scripts": {
"start" : "npm-run-all --parallel watch:server watch:build",
"watch:build" : "webpack --watch",
"watch:server" : "nodemon \"./dist/index.js\" --watch \"./dist\""
},
...
}
After doing so, you can easily run your project by using npm start.
Don't forget config WatchIgnorePlugin for webpack to ignore ./dist folder.
Dependencies
npm-run-all - A CLI tool to run multiple npm-scripts in parallel or sequential.
webpack - webpack is a module bundler. Its main purpose is to bundle JavaScript files for usage in a browser, yet it is also capable of transforming, bundling, or packaging just about any resource or asset.
nodemon - Simple monitor script for use during development of a node.js app.
Faced the same problem and found the next solution - webpack-shell-plugin.
It
allows you to run any shell commands before or after webpack builds
So, thats my scripts in package.json:
"scripts": {
"clean": "rimraf build",
"prestart": "npm run clean",
"start": "webpack --config webpack.client.config.js",
"poststart": "webpack --watch --config webpack.server.config.js",
}
If I run 'start' script it launches next script sequence: clean -> start -> poststart.
And there is part of 'webpack.server.config.js':
var WebpackShellPlugin = require('webpack-shell-plugin');
...
if (process.env.NODE_ENV !== 'production') {
config.plugins.push(new WebpackShellPlugin({onBuildEnd: ['nodemon build/server.js --watch build']}));
}
...
"onBuildEnd" event fires only once after first build, rebuilds are not trigger "onBuildEnd", so nodemon works as intended
I like the simplicity of nodemon-webpack-plugin
webpack.config.js
const NodemonPlugin = require('nodemon-webpack-plugin')
module.exports = {
plugins: [new NodemonPlugin()]
}
then just run webpack with the watch flag
webpack --watch
In addition to #Ling's good answer:
If you want to build your project once, before you watch it with nodemon, you can use a webpack compiler hook. The plugin's code triggers nodemon in the done hook once after webpack has finished its compilation (see also this helpful post).
const { spawn } = require("child_process")
function OnFirstBuildDonePlugin() {
let isInitialBuild = true
return {
apply: compiler => {
compiler.hooks.done.tap("OnFirstBuildDonePlugin", compilation => {
if (isInitialBuild) {
isInitialBuild = false
spawn("nodemon dist/index.js --watch dist", {
stdio: "inherit",
shell: true
})
}
})
}
}
}
webpack.config.js:
module.exports = {
...
plugins: [
...
OnFirstBuildDonePlugin()
]
})
package.json:
"scripts": {
"dev" : "webpack --watch"
},
Hope, it helps.
There's no need to use plugins here. You could try running multiple nodemon instances like below. Try modifying the following script for your use case, and see if it works for you:
"scripts": {
"start": "nodemon --ignore './public/' ./bin/www & nodemon --ignore './public/' --exec 'yarn webpack'",
"webpack": "webpack --config frontend/webpack.config.js"
}
You don't need any plugins to use webpack and nodemon, just use this scripts on your package.json
"scripts": {
"start": "nodemon --ignore './client/dist' -e js,ejs,html,css --exec 'npm run watch'",
"watch": "npm run build && node ./server/index.js",
"build": "rimraf ./client/dist && webpack --bail --progress --profile"
},
#Ling has an answer very close to being correct. But it errors the first time somebody runs watch. You'll need to modify the solution as so to prevent errors.
Run npm install npm-run-all webpack nodemon
Create a file called watch-shim.js in your root. Add the following contents, which will create a dummy file and directory if they're missing.
var fs = require('fs');
if (!fs.existsSync('./dist')) {
fs.mkdir('./dist');
fs.writeFileSync('./dist/bundle.js', '');
}
Setup your scripts as so in package.json. This will only run watch if the watch-shim.js file runs successfully. Thereby preventing Nodemon from crashing due to missing files on the first run.
{
...
"scripts": {
"start": "npm run watch",
"watch": "node watch-shim.js && npm-run-all --parallel watch:server watch:build",
"watch:build": "webpack --progress --colors --watch",
"watch:server": "nodemon \"./dist/bundle.js\" --watch \"./dist/*\""
}
...
},
Assuming nodemon server.js touch the server.js file afterEmit:
// webpack.config.js
module.exports = {
// ...
plugins: [
// ...,
// 👇
apply: (compiler) => {
compiler.hooks.afterEmit.tap('AfterEmitPlugin', (compilation) => {
require('child_process').execSync('touch server.js') // $ touch server.js
});
}
]
}
I tried most of the solution provided above. I believe the best one is to use nodemon-webpack-plugin .
It is very simple to use i.e. just add
const NodemonPlugin = require('nodemon-webpack-plugin')
to webpack file with
new NodemonPlugin() as your plugin.
Below are the scripts to use it:
"scripts": {
"watch:webpack-build-dev": "webpack --watch --mode development",
"clean-db": "rm -rf ./db && mkdir -p ./db",
"local-dev": "npm run clean-db && npm run watch:webpack-build-dev"
...
}
After this you can simply run npm run local-dev.
Adding a module to development is usually not as bad as adding to a production one. And mostly you will be using it for the development anyway.
This also doesn't require any additional package like nodemon or npm-run-all etc.
Also nodemon-webpack-plugin only works in watch mode.

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