Passing an argument to npm run script - node.js

I am creating a script in npm package.json.
The script will run yeoman to scaffold my template and then I want to run a gulp task to do some more stuff to a specific file (inject using gulp-inject)
The npm task looks like this:
"scaffolt": "scaffolt -g scaffolt/generators template && gulp inject"
Now, i need to be able to call the command from the command line giving a name to my template.
The command I need to run is the following:
npm run scaffolt {templateName}
but if I do this, then I try to run a gulp task called the same as the typed {templateName}.
A quick example: If I run npm run scaffolt myTemplate then the second part of this will try to run a task called gulp myTemplate, failing.
Is there any way to pass the {myTemplate} name as an argument to the second part of the script so that it can be used in the gulptask?
The gulp task currently only console.log the process.argv.

You can pass arguments to the npm run-script. Here is the documentation.
Make gulp tasks for these operations.
//gulpfile.js
const gulp = require('gulp');
const commandLineArgs = require('command-line-args');
const spawn = require('child_process').spawn;
gulp.task('inject', ['scaffolt'], () => {
console.log('scaffolt complete!');
});
gulp.task('scaffolt', (cb) => {
const options = commandLineArgs([{ name: 'templateName' }]);
//use scaffolt.cmd on Windows!
spawn('scaffolt', ['-g', 'scaffolt/generators', options.templateName])
.on('close', cb);
});
And in your package
//package.json
"scripts": {
"scaffolt": "gulp inject "
}
And to run it npm run scaffolt -- --templateName=something
Tip: npm run-script appends node_modules/.bin directory in the PATH so we can spawn executables just like they are on the same folder!

You can use magical $npm_config_<exampleVarName> in script definition and then pass the value of it either from env variable named match exampleVarName or pass it in command line you add --exampleVarName=ValueHere
in your case
//package.json
"scripts": {
"scaffolt": "scaffolt -g scaffolt/generators $npm_config_templateName && gulp inject"
}
then run it as
npm run scaffolt --templateName=whatever

Related

Node v15.5.0 doesn't read command line flags [duplicate]

The scripts portion of my package.json currently looks like this:
"scripts": {
"start": "node ./script.js server"
}
...which means I can run npm start to start the server. So far so good.
However, I would like to be able to run something like npm start 8080 and have the argument(s) passed to script.js (e.g. npm start 8080 => node ./script.js server 8080). Is this possible?
npm 2 and newer
It's possible to pass args to npm run since npm 2 (2014). The syntax is as follows:
npm run <command> [-- <args>]
Note the -- separator, used to separate the params passed to npm command itself, and the params passed to your script.
With the example package.json:
"scripts": {
"grunt": "grunt",
"server": "node server.js"
}
here's how to pass the params to those scripts:
npm run grunt -- task:target // invokes `grunt task:target`
npm run server -- --port=1337 // invokes `node server.js --port=1337`
Note: If your param does not start with - or --, then having an explicit -- separator is not needed; but it's better to do it anyway for clarity.
npm run grunt task:target // invokes `grunt task:target`
Note below the difference in behavior (test.js has console.log(process.argv)): the params which start with - or -- are passed to npm and not to the script, and are silently swallowed there.
$ npm run test foobar
['C:\\Program Files\\nodejs\\node.exe', 'C:\\git\\myrepo\\test.js', 'foobar']
$ npm run test -foobar
['C:\\Program Files\\nodejs\\node.exe', 'C:\\git\\myrepo\\test.js']
$ npm run test --foobar
['C:\\Program Files\\nodejs\\node.exe', 'C:\\git\\myrepo\\test.js']
$ npm run test -- foobar
['C:\\Program Files\\nodejs\\node.exe', 'C:\\git\\myrepo\\test.js', 'foobar']
$ npm run test -- -foobar
['C:\\Program Files\\nodejs\\node.exe', 'C:\\git\\myrepo\\test.js', '-foobar']
$ npm run test -- --foobar
['C:\\Program Files\\nodejs\\node.exe', 'C:\\git\\myrepo\\test.js', '--foobar']
The difference is clearer when you use a param actually used by npm:
$ npm test --help // this is disguised `npm --help test`
npm test [-- <args>]
aliases: tst, t
To get the parameter value, see this question. For reading named parameters, it's probably best to use a parsing library like yargs or minimist; nodejs exposes process.argv globally, containing command line parameter values, but this is a low-level API (whitespace-separated array of strings, as provided by the operating system to the node executable).
You asked to be able to run something like npm start 8080. This is possible without needing to modify script.js or configuration files as follows.
For example, in your "scripts" JSON value, include--
"start": "node ./script.js server $PORT"
And then from the command-line:
$ PORT=8080 npm start
I have confirmed that this works using bash and npm 1.4.23. Note that this work-around does not require GitHub npm issue #3494 to be resolved.
You could also do that:
In package.json:
"scripts": {
"cool": "./cool.js"
}
In cool.js:
console.log({ myVar: process.env.npm_config_myVar });
In CLI:
npm --myVar=something run-script cool
Should output:
{ myVar: 'something' }
Update: Using npm 3.10.3, it appears that it lowercases the process.env.npm_config_ variables? I'm also using better-npm-run, so I'm not sure if this is vanilla default behavior or not, but this answer is working. Instead of process.env.npm_config_myVar, try process.env.npm_config_myvar
jakub.g's answer is correct, however an example using grunt seems a bit complex.
So my simpler answer:
- Sending a command line argument to an npm script
Syntax for sending command line arguments to an npm script:
npm run [command] [-- <args>]
Imagine we have an npm start task in our package.json to kick off webpack dev server:
"scripts": {
"start": "webpack-dev-server --port 5000"
},
We run this from the command line with npm start
Now if we want to pass in a port to the npm script:
"scripts": {
"start": "webpack-dev-server --port process.env.port || 8080"
},
running this and passing the port e.g. 5000 via command line would be as follows:
npm start --port:5000
- Using package.json config:
As mentioned by jakub.g, you can alternatively set params in the config of your package.json
"config": {
"myPort": "5000"
}
"scripts": {
"start": "webpack-dev-server --port process.env.npm_package_config_myPort || 8080"
},
npm start will use the port specified in your config, or alternatively you can override it
npm config set myPackage:myPort 3000
- Setting a param in your npm script
An example of reading a variable set in your npm script. In this example NODE_ENV
"scripts": {
"start:prod": "NODE_ENV=prod node server.js",
"start:dev": "NODE_ENV=dev node server.js"
},
read NODE_ENV in server.js either prod or dev
var env = process.env.NODE_ENV || 'prod'
if(env === 'dev'){
var app = require("./serverDev.js");
} else {
var app = require("./serverProd.js");
}
As of npm 2.x, you can pass args into run-scripts by separating with --
Terminal
npm run-script start -- --foo=3
Package.json
"start": "node ./index.js"
Index.js
console.log('process.argv', process.argv);
I had been using this one-liner in the past, and after a bit of time away from Node.js had to try and rediscover it recently. Similar to the solution mentioned by #francoisrv, it utilizes the npm_config_* variables.
Create the following minimal package.json file:
{
"name": "argument",
"version": "1.0.0",
"scripts": {
"argument": "echo \"The value of --foo is '${npm_config_foo}'\""
}
}
Run the following command:
npm run argument --foo=bar
Observe the following output:
The value of --foo is 'bar'
All of this is nicely documented in the npm official documentation:
https://docs.npmjs.com/using-npm/config
Note: The Environment Variables heading explains that variables inside scripts do behave differently to what is defined in the documentation. This is true when it comes to case sensitivity, as well whether the argument is defined with a space or equals sign.
Note: If you are using an argument with hyphens, these will be replaced with underscores in the corresponding environment variable. For example, npm run example --foo-bar=baz would correspond to ${npm_config_foo_bar}.
Note: For non-WSL Windows users, see #Doctor Blue's comments below... TL;DR replace ${npm_config_foo} with %npm_config_foo%.
Use process.argv in your code then just provide a trailing $* to your scripts value entry.
As an example try it with a simple script which just logs the provided arguments to standard out echoargs.js:
console.log('arguments: ' + process.argv.slice(2));
package.json:
"scripts": {
"start": "node echoargs.js $*"
}
Examples:
> npm start 1 2 3
arguments: 1,2,3
process.argv[0] is the executable (node), process.argv[1] is your script.
Tested with npm v5.3.0 and node v8.4.0
Most of the answers above cover just passing the arguments into your NodeJS script, called by npm. My solution is for general use.
Just wrap the npm script with a shell interpreter (e.g. sh) call and pass the arguments as usual. The only exception is that the first argument number is 0.
For example, you want to add the npm script someprogram --env=<argument_1>, where someprogram just prints the value of the env argument:
package.json
"scripts": {
"command": "sh -c 'someprogram --env=$0'"
}
When you run it:
% npm run -s command my-environment
my-environment
If you want to pass arguments to the middle of an npm script, as opposed to just having them appended to the end, then inline environment variables seem to work nicely:
"scripts": {
"dev": "BABEL_ARGS=-w npm run build && cd lib/server && nodemon index.js",
"start": "npm run build && node lib/server/index.js",
"build": "mkdir -p lib && babel $BABEL_ARGS -s inline --stage 0 src -d lib",
},
Here, npm run dev passes the -w watch flag to babel, but npm run start just runs a regular build once.
For PowerShell users on Windows
The accepted answer did not work for me with npm 6.14. Neither adding no -- nor including it once does work. However, putting -- twice or putting "--" once before the arguments does the trick. Example:
npm run <my_script> -- -- <my arguments like --this>
Suspected reason
Like in bash, -- instructs PowerShell to treat all following arguments as literal strings, and not options (E.g see this answer). The issues seems to be that the command is interpreted one time more than expected, loosing the '--'. For instance, by doing
npm run <my_script> -- --option value
npm will run
<my_script> value
However, doing
npm run <my_script> "--" --option value
results in
<my_script> "--option" "value"
which works fine.
This doesn't really answer your question but you could always use environment variables instead:
"scripts": {
"start": "PORT=3000 node server.js"
}
Then in your server.js file:
var port = process.env.PORT || 3000;
I've found this question while I was trying to solve my issue with running sequelize seed:generate cli command:
node_modules/.bin/sequelize seed:generate --name=user
Let me get to the point. I wanted to have a short script command in my package.json file and to provide --name argument at the same time
The answer came after some experiments. Here is my command in package.json
"scripts: {
"seed:generate":"NODE_ENV=development node_modules/.bin/sequelize seed:generate"
}
... and here is an example of running it in terminal to generate a seed file for a user
> yarn seed:generate --name=user
> npm run seed:generate -- --name=user
FYI
yarn -v
1.6.0
npm -v
5.6.0
Note: This approach modifies your package.json on the fly, use it if you have no alternative.
I had to pass command line arguments to my scripts which were something like:
"scripts": {
"start": "npm run build && npm run watch",
"watch": "concurrently \"npm run watch-ts\" \"npm run watch-node\"",
...
}
So, this means I start my app with npm run start.
Now if I want to pass some arguments, I would start with maybe:
npm run start -- --config=someConfig
What this does is: npm run build && npm run watch -- --config=someConfig. Problem with this is, it always appends the arguments to the end of the script. This means all the chained scripts don't get these arguments(Args maybe or may not be required by all, but that's a different story.). Further when the linked scripts are called then those scripts won't get the passed arguments. i.e. The watch script won't get the passed arguments.
The production usage of my app is as an .exe, so passing the arguments in the exe works fine but if want to do this during development, it gets problamatic.
I couldn't find any proper way to achieve this, so this is what I have tried.
I have created a javascript file: start-script.js at the parent level of the application, I have a "default.package.json" and instead of maintaining "package.json", I maintain "default.package.json". The purpose of start-script.json is to read default.package.json, extract the scripts and look for npm run scriptname then append the passed arguments to these scripts. After this, it will create a new package.json and copy the data from default.package.json with modified scripts and then call npm run start.
const fs = require('fs');
const { spawn } = require('child_process');
// open default.package.json
const defaultPackage = fs.readFileSync('./default.package.json');
try {
const packageOb = JSON.parse(defaultPackage);
// loop over the scripts present in this object, edit them with flags
if ('scripts' in packageOb && process.argv.length > 2) {
const passedFlags = ` -- ${process.argv.slice(2).join(' ')}`;
// assuming the script names have words, : or -, modify the regex if required.
const regexPattern = /(npm run [\w:-]*)/g;
const scriptsWithFlags = Object.entries(packageOb.scripts).reduce((acc, [key, value]) => {
const patternMatches = value.match(regexPattern);
// loop over all the matched strings and attach the desired flags.
if (patternMatches) {
for (let eachMatchedPattern of patternMatches) {
const startIndex = value.indexOf(eachMatchedPattern);
const endIndex = startIndex + eachMatchedPattern.length;
// save the string which doen't fall in this matched pattern range.
value = value.slice(0, startIndex) + eachMatchedPattern + passedFlags + value.slice(endIndex);
}
}
acc[key] = value;
return acc;
}, {});
packageOb.scripts = scriptsWithFlags;
}
const modifiedJSON = JSON.stringify(packageOb, null, 4);
fs.writeFileSync('./package.json', modifiedJSON);
// now run your npm start script
let cmd = 'npm';
// check if this works in your OS
if (process.platform === 'win32') {
cmd = 'npm.cmd'; // https://github.com/nodejs/node/issues/3675
}
spawn(cmd, ['run', 'start'], { stdio: 'inherit' });
} catch(e) {
console.log('Error while parsing default.package.json', e);
}
Now, instead of doing npm run start, I do node start-script.js --c=somethis --r=somethingElse
The initial run looks fine, but haven't tested thoroughly. Use it, if you like for you app development.
I find it's possible to just pass variables exactly as you would to Node.js:
// index.js
console.log(process.env.TEST_ENV_VAR)
// package.json
...
"scripts": { "start": "node index.js" },
...
TEST_ENV_VAR=hello npm start
Prints out "hello"
From what I see, people use package.json scripts when they would like to run script in simpler way. For example, to use nodemon that installed in local node_modules, we can't call nodemon directly from the cli, but we can call it by using ./node_modules/nodemon/nodemon.js. So, to simplify this long typing, we can put this...
...
scripts: {
'start': 'nodemon app.js'
}
...
... then call npm start to use 'nodemon' which has app.js as the first argument.
What I'm trying to say, if you just want to start your server with the node command, I don't think you need to use scripts. Typing npm start or node app.js has the same effort.
But if you do want to use nodemon, and want to pass a dynamic argument, don't use script either. Try to use symlink instead.
For example using migration with sequelize. I create a symlink...
ln -s node_modules/sequelize/bin/sequelize sequelize
... And I can pass any arguement when I call it ...
./sequlize -h /* show help */
./sequelize -m /* upgrade migration */
./sequelize -m -u /* downgrade migration */
etc...
At this point, using symlink is the best way I could figure out, but I don't really think it's the best practice.
I also hope for your opinion to my answer.
Separate your arguments using -- from the script and add all the required arguments, we can later access them by index.
npm run start -- myemail#gmail.com 100
You can get params in node using
const params = process.argv.slice(2);
console.log(params);
Output
['myemail#gmail.com', '100']
I know there is an approved answer already, but I kinda like this JSON approach.
npm start '{"PROJECT_NAME_STR":"my amazing stuff", "CRAZY_ARR":[0,7,"hungry"], "MAGICAL_NUMBER_INT": 42, "THING_BOO":true}';
Usually I have like 1 var I need, such as a project name, so I find this quick n' simple.
Also I often have something like this in my package.json
"scripts": {
"start": "NODE_ENV=development node local.js"
}
And being greedy I want "all of it", NODE_ENV and the CMD line arg stuff.
You simply access these things like so in your file (in my case local.js)
console.log(process.env.NODE_ENV, starter_obj.CRAZY_ARR, starter_obj.PROJECT_NAME_STR, starter_obj.MAGICAL_NUMBER_INT, starter_obj.THING_BOO);
You just need to have this bit above it (I'm running v10.16.0 btw)
var starter_obj = JSON.parse(JSON.parse(process.env.npm_config_argv).remain[0]);
Anyhoo, question already answered. Thought I'd share, as I use this method a lot.
I settled for something like this, look at the test-watch script:
"scripts": {
"dev": "tsc-watch --onSuccess \"node ./dist/server.js\"",
"test": "tsc && cross-env NODE_OPTIONS=--experimental-vm-modules NODE_NO_WARNINGS=1 jest",
"test-watch": "cross-env NODE_OPTIONS=--experimental-vm-modules NODE_NO_WARNINGS=1 tsc-watch --onSuccess",
},
You invoke the test-watch script like this:
// Run all tests with odata in their name
npm run test-watch "jest odata"
npm run script_target -- < argument > Basically this is the way of passing the command line arguments but it will work only in case of when script have only one command running like I am running a command i.e. npm run start -- 4200
"script":{
"start" : "ng serve --port="
}
This will run for passing command line parameters but what if we run more then one command together like npm run build c:/workspace/file
"script":{
"build" : "copy c:/file <arg> && ng build"
}
but it will interpreter like this while running copy c:/file && ng build c:/work space/file
and we are expected something like this
copy c:/file c:/work space/file && ng build
Note :- so command line parameter only work ad expected in case of only one command in a script.
I read some answers above in which some of them are writing that you can access the command line parameter using $ symbol but this will not gonna work
Try cross-env NPM package.
Easy to use. Easy to install. Cross all platform.
Example:
set arguments for command
// package.json
"scripts": {
“test”: “node test.js”,
“test-with-env-arg”: “cross-env YourEnvVarName=strValue yarn test,
}
get arguments from process.env
// test.js
const getCommandLineArg = Boolean(process.env.YourEnvVarName === 'true') // Attention: value of process.env.* is String type, not number || boolean
i had the same issue when i need to deploy to different environments
here is the package.json pre and post the updates.
scripts:
{"deploy-sit": "sls deploy --config resources-sit.yml",
"deploy-uat": "sls deploy --config resources-uat.yml",
"deploy-dev": "sls deploy --config resources-dev.yml"}
but here is the correct method to adopt the environment variables rather than repeating ourselves
scripts:{"deploy-env": "sls deploy --config resources-$ENV_VAR.yml"}
finally you can deploy by running
ENV_VAR=dev npm run deploy-env

How to disable warnings when node is launched via a (global) shell script

I am building a CLI tool with node, and want to use the fs.promise API. However, when the app is launched, there's always an ExperimentalWarning, which is super annoying and messes up with the interaction prompts. How can I disable this warning/all warnings?
I'm testing this with the latest node v10 lts release on Windows 10.
To use the CLI tool globally, I have added this to my package.json file:
{
//...
"preferGlobal": true,
"bin": { "myapp" : "./index.js" }
//...
}
And have run npm link to link the ./index.js script. Then I am able to run the app globally simply with myapp.
After some research I noticed that there are generally 2 ways to disable the warnings:
set environmental variable NODE_NO_WARNINGS=1
call the script with node --no-warnings ./index.js
Although I was able to disable the warnings with the 2 methods above, there seems to be no way to do that while directly running myapp command.
The shebang I placed in the entrance script ./index.js is:
#!/usr/bin/env node
// my code...
I have also read other discussions on modifying the shebang, but haven't found a universal/cross-platform way to do this - to either pass argument to node itself, or set the env variable.
If I publish this npm package, it would be great if there's a way to make sure the warnings of this single package are disabled in advance, instead of having each individual user tweak their environment themselves. Is there any hidden npm package.json configs that allow this?
Any help would be greatly appreciated!
I am now using a launcher script to spawn a child_process to work around this limitation. Ugly, but it works with npm link, global installs and whatnot.
#!/usr/bin/env node
const { spawnSync } = require("child_process");
const { resolve } = require("path");
// Say our original entrance script is `app.js`
const cmd = "node --no-warnings " + resolve(__dirname, "app.js");
spawnSync(cmd, { stdio: "inherit", shell: true });
As it's kind of like a hack, I won't be using this method next time, and will instead be wrapping the original APIs in a promise manually, sticking to util.promisify, or using the blocking/sync version of the APIs.
I configured my test script like this:
"scripts": {
"test": "tsc && cross-env NODE_OPTIONS=--experimental-vm-modules NODE_NO_WARNINGS=1 jest"
},
Notice the NODE_NO_WARNINGS=1 part. It disables the warnings I was getting from setting NODE_OPTIONS=--experimental-vm-modules
Here's what I'm using to run node with a command line flag:
#!/bin/sh
_=0// "exec" "/usr/bin/env" "node" "--experimental-repl-await" "$0" "$#"
// Your normal Javascript here
The first line tells the shell to use /bin/sh to run the script. The second line is a bit magical. To the shell it's a variable assignment _=0// followed by "exec" ....
Node sees it as a variable assignment followed by a comment - so it's almost a nop apart from the side effect of assigning 0 to _.
The result is that when the shell reaches line 2 it will exec node (via env) with any command line options you need.
New answer: You can also catch emitted warnings in your script and choose which ones to prevent from being logged
const originalEmit = process.emit;
process.emit = function (name, data, ...args) {
if (
name === `warning` &&
typeof data === `object` &&
data.name === `ExperimentalWarning`
//if you want to only stop certain messages, test for the message here:
//&& data.message.includes(`Fetch API`)
) {
return false;
}
return originalEmit.apply(process, arguments);
};
Inspired by this patch to yarn

How to create a "rebuild" task in gulp?

gulp.task('build', function () {
// Build, generate files...
});
gulp.task('clear', function () {
// Delete generated files.
});
gulp.task('rebuild', function () {
// First: clear
// Then: build
});
In most case, "build" task doesn't need previous generated files to be removed (which slows the build process).
But there is times when I want to run "clear" and "build" task in one command:
Of course "rebuild" task depends on "clear" and "build", but if I use dependency hint like
gulp.task('rebuild', ['clear', 'build']);
the two tasks run asynchronously, which results in unexpected problem!
The easy way to solve this problem is run:
gulp clear
gulp build
but a single command
gulp rebuild
is easier, right? :P
By the way, gulp.series() has been deprecated...
It's not perfect but should work. Extract build task into a function. Then excute in the build and rebuild tasks.
var build = function() {
return gulp.src().concat();
}
gulp.task('build', function () {
return build();
});
gulp.task('clear', function () {
// Delete generated files.
});
gulp.task('rebuild', ['clear'], function () {
return build();
});
My solution isn't via Gulp as you requested, but NPM may be a better choice since you probably have NPM right there handy. All you're trying to do is save a few keystrokes.
Add an NPM script "rg" (rebuild-gulp) which does what you need:
"scripts": {
"rg": "gulp clear && gulp build"
}
Invoke with npm run rg

Gulp + Webpack or JUST Webpack?

I see people using gulp with webpack. But then I read webpack can replace gulp? I'm completely confused here...can someone explain?
UPDATE
in the end I started with gulp. I was new to modern front-end and just wanted to get up and running quick. Now that I've got my feet quite wet after more than a year, I'm ready to move to webpack. I suggest the same route for people who start off in the same shoes. Not saying you can't try webpack but just sayin if it seems complicated start with gulp first...nothing wrong with that.
If you don't want gulp, yes there's grunt but you could also just specify commands in your package.json and call them from the command-line without a task runner just to get up and running initially. For example:
"scripts": {
"babel": "babel src -d build",
"browserify": "browserify build/client/app.js -o dist/client/scripts/app.bundle.js",
"build": "npm run clean && npm run babel && npm run prepare && npm run browserify",
"clean": "rm -rf build && rm -rf dist",
"copy:server": "cp build/server.js dist/server.js",
"copy:index": "cp src/client/index.html dist/client/index.html",
"copy": "npm run copy:server && npm run copy:index",
"prepare": "mkdir -p dist/client/scripts/ && npm run copy",
"start": "node dist/server"
},
This answer might help. Task Runners (Gulp, Grunt, etc) and Bundlers (Webpack, Browserify). Why use together?
...and here's an example of using webpack from within a gulp task. This goes a step further and assumes that your webpack config is written in es6.
var gulp = require('gulp');
var webpack = require('webpack');
var gutil = require('gutil');
var babel = require('babel/register');
var config = require(path.join('../..', 'webpack.config.es6.js'));
gulp.task('webpack-es6-test', function(done){
webpack(config).run(onBuild(done));
});
function onBuild(done) {
return function(err, stats) {
if (err) {
gutil.log('Error', err);
if (done) {
done();
}
} else {
Object.keys(stats.compilation.assets).forEach(function(key) {
gutil.log('Webpack: output ', gutil.colors.green(key));
});
gutil.log('Webpack: ', gutil.colors.blue('finished ', stats.compilation.name));
if (done) {
done();
}
}
}
}
I think you'll find that as your app gets more complicated, you might want to use gulp with a webpack task as per example above. This allows you to do a few more interesting things in your build that webpack loaders and plugins really don't do, ie. creating output directories, starting servers, etc. Well, to be succinct, webpack actually can do those things, but you might find them limited for your long term needs. One of the biggest advantages you get from gulp -> webpack is that you can customize your webpack config for different environments and have gulp do the right task for the right time. Its really up to you, but there's nothing wrong with running webpack from gulp, in fact there's some pretty interesting examples of how to do it. The example above is basically from jlongster.
NPM scripts can do the same as gulp, but in about 50x less code. In fact, with no code at all, only command line arguments.
For example, the use case you described where you want to have different code for different environments.
With Webpack + NPM Scripts, it's this easy:
"prebuild:dev": "npm run clean:wwwroot",
"build:dev": "cross-env NODE_ENV=development webpack --config config/webpack.development.js --hot --profile --progress --colors --display-cached",
"postbuild:dev": "npm run copy:index.html && npm run rename:index.html",
"prebuild:production": "npm run clean:wwwroot",
"build:production": "cross-env NODE_ENV=production webpack --config config/webpack.production.js --profile --progress --colors --display-cached --bail",
"postbuild:production": "npm run copy:index.html && npm run rename:index.html",
"clean:wwwroot": "rimraf -- wwwroot/*",
"copy:index.html": "ncp wwwroot/index.html Views/Shared",
"rename:index.html": "cd ../PowerShell && elevate.exe -c renamer --find \"index.html\" --replace \"_Layout.cshtml\" \"../MyProject/Views/Shared/*\"",
Now you simply maintain two webpack config scripts, one for development mode, webpack.development.js, and one for production mode, webpack.production.js. I also utilize a webpack.common.js which houses webpack config shared on all environments, and use webpackMerge to merge them.
Because of the coolness of NPM scripts, it allows for easy chaining, similar to how gulp does Streams/pipes.
In the example above, to build for developement, you simply go to your command line and execute npm run build:dev.
NPM would first run prebuild:dev,
Then build:dev,
And finally postbuild:dev.
The pre and post prefixes tell NPM which order to execute in.
If you notice, with Webpack + NPM scripts, you can run a native programs, such as rimraf, instead of a gulp-wrapper for a native program such as gulp-rimraf. You can also run native Windows .exe files as I did here with elevate.exe or native *nix files on Linux or Mac.
Try doing the same thing with gulp. You'll have to wait for someone to come along and write a gulp-wrapper for the native program you want to use. In addition, you'll likely need to write convoluted code like this: (taken straight from angular2-seed repo)
Gulp Development code
import * as gulp from 'gulp';
import * as gulpLoadPlugins from 'gulp-load-plugins';
import * as merge from 'merge-stream';
import * as util from 'gulp-util';
import { join/*, sep, relative*/ } from 'path';
import { APP_DEST, APP_SRC, /*PROJECT_ROOT, */TOOLS_DIR, TYPED_COMPILE_INTERVAL } from '../../config';
import { makeTsProject, templateLocals } from '../../utils';
const plugins = <any>gulpLoadPlugins();
let typedBuildCounter = TYPED_COMPILE_INTERVAL; // Always start with the typed build.
/**
* Executes the build process, transpiling the TypeScript files (except the spec and e2e-spec files) for the development
* environment.
*/
export = () => {
let tsProject: any;
let typings = gulp.src([
'typings/index.d.ts',
TOOLS_DIR + '/manual_typings/**/*.d.ts'
]);
let src = [
join(APP_SRC, '**/*.ts'),
'!' + join(APP_SRC, '**/*.spec.ts'),
'!' + join(APP_SRC, '**/*.e2e-spec.ts')
];
let projectFiles = gulp.src(src);
let result: any;
let isFullCompile = true;
// Only do a typed build every X builds, otherwise do a typeless build to speed things up
if (typedBuildCounter < TYPED_COMPILE_INTERVAL) {
isFullCompile = false;
tsProject = makeTsProject({isolatedModules: true});
projectFiles = projectFiles.pipe(plugins.cached());
util.log('Performing typeless TypeScript compile.');
} else {
tsProject = makeTsProject();
projectFiles = merge(typings, projectFiles);
}
result = projectFiles
.pipe(plugins.plumber())
.pipe(plugins.sourcemaps.init())
.pipe(plugins.typescript(tsProject))
.on('error', () => {
typedBuildCounter = TYPED_COMPILE_INTERVAL;
});
if (isFullCompile) {
typedBuildCounter = 0;
} else {
typedBuildCounter++;
}
return result.js
.pipe(plugins.sourcemaps.write())
// Use for debugging with Webstorm/IntelliJ
// https://github.com/mgechev/angular2-seed/issues/1220
// .pipe(plugins.sourcemaps.write('.', {
// includeContent: false,
// sourceRoot: (file: any) =>
// relative(file.path, PROJECT_ROOT + '/' + APP_SRC).replace(sep, '/') + '/' + APP_SRC
// }))
.pipe(plugins.template(templateLocals()))
.pipe(gulp.dest(APP_DEST));
};
Gulp Production code
import * as gulp from 'gulp';
import * as gulpLoadPlugins from 'gulp-load-plugins';
import { join } from 'path';
import { TMP_DIR, TOOLS_DIR } from '../../config';
import { makeTsProject, templateLocals } from '../../utils';
const plugins = <any>gulpLoadPlugins();
const INLINE_OPTIONS = {
base: TMP_DIR,
useRelativePaths: true,
removeLineBreaks: true
};
/**
* Executes the build process, transpiling the TypeScript files for the production environment.
*/
export = () => {
let tsProject = makeTsProject();
let src = [
'typings/index.d.ts',
TOOLS_DIR + '/manual_typings/**/*.d.ts',
join(TMP_DIR, '**/*.ts')
];
let result = gulp.src(src)
.pipe(plugins.plumber())
.pipe(plugins.inlineNg2Template(INLINE_OPTIONS))
.pipe(plugins.typescript(tsProject))
.once('error', function () {
this.once('finish', () => process.exit(1));
});
return result.js
.pipe(plugins.template(templateLocals()))
.pipe(gulp.dest(TMP_DIR));
};
The actual gulp code is much more complicated that this, as this is only 2 of the several dozen gulp files in the repo.
So, which one is easier to you?
In my opinion, NPM scripts far surpasses gulp and grunt, in both effectiveness and ease of use, and all front-end developers should consider using it in their workflow because it is a major time saver.
UPDATE
There is one scenario I've encountered where I wanted to use Gulp in combination with NPM scripts and Webpack.
When I need to do remote debugging on an iPad or Android device for example, I need to start up extra servers. In the past I ran all the servers as separate processes, from within IntelliJ IDEA (Or Webstorm) that is easy with the "Compound" Run Configuration. But if I need to stop and restart them, it was tedious to have to close 5 different server tabs, plus the output was spread across the different windows.
One of the benefits of gulp is that is can chain all the output from separate independent processes into one console window, which becomes the parent of all the child servers.
So I created a very simple gulp task that just runs my NPM scripts or the commands directly, so all the output appears in one window, and I can easily end all 5 servers at once by closing the gulp task window.
Gulp.js
/**
* Gulp / Node utilities
*/
var gulp = require('gulp-help')(require('gulp'));
var utils = require('gulp-util');
var log = utils.log;
var con = utils.colors;
/**
* Basic workflow plugins
*/
var shell = require('gulp-shell'); // run command line from shell
var browserSync = require('browser-sync');
/**
* Performance testing plugins
*/
var ngrok = require('ngrok');
// Variables
var serverToProxy1 = "localhost:5000";
var finalPort1 = 8000;
// When the user enters "gulp" on the command line, the default task will automatically be called. This default task below, will run all other tasks automatically.
// Default task
gulp.task('default', function (cb) {
console.log('Starting dev servers!...');
gulp.start(
'devserver:jit',
'nodemon',
'browsersync',
'ios_webkit_debug_proxy'
'ngrok-url',
// 'vorlon',
// 'remotedebug_ios_webkit_adapter'
);
});
gulp.task('nodemon', shell.task('cd ../backend-nodejs && npm run nodemon'));
gulp.task('devserver:jit', shell.task('npm run devserver:jit'));
gulp.task('ios_webkit_debug_proxy', shell.task('npm run ios-webkit-debug-proxy'));
gulp.task('browsersync', shell.task(`browser-sync start --proxy ${serverToProxy1} --port ${finalPort1} --no-open`));
gulp.task('ngrok-url', function (cb) {
return ngrok.connect(finalPort1, function (err, url) {
site = url;
log(con.cyan('ngrok'), '- serving your site from', con.yellow(site));
cb();
});
});
// gulp.task('vorlon', shell.task('vorlon'));
// gulp.task('remotedebug_ios_webkit_adapter', shell.task('remotedebug_ios_webkit_adapter'));
Still quite a bit of code just to run 5 tasks, in my opinion, but it works for the purpose. One caveate is that gulp-shell doesn't seem to run some commands correctly, such as ios-webkit-debug-proxy. So I had to create an NPM Script that just executes the same command, and then it works.
So I primarily use NPM Scripts for all my tasks, but occasionally when I need to run a bunch of servers at once, I'll fire up my Gulp task to help out. Pick the right tool for the right job.
UPDATE 2
I now use a script called concurrently which does the same thing as the gulp task above. It runs multiple CLI scripts in parallel and pipes them all to the same console window, and its very simple to use. Once again, no code required (well, the code is inside the node_module for concurrently, but you don't have to concern yourself with that)
// NOTE: If you need to run a command with spaces in it, you need to use
// double quotes, and they must be escaped (at least on windows).
// It doesn't seem to work with single quotes.
"run:all": "concurrently \"npm run devserver\" nodemon browsersync ios_webkit_debug_proxy ngrok-url"
This runs all 5 scripts in parallel piped out to one terminal. Awesome! So that this point, I rarely use gulp, since there are so many cli scripts to do the same tasks with no code.
I suggest you read these articles which compare them in depth.
How to Use NPM as a Build Tool
Why we should stop using Grunt & Gulp
Why I Left Gulp and Grunt for NPM Scripts
I used both options in my different projects.
Here is one boilerplate that I put together using gulp with webpack - https://github.com/iroy2000/react-reflux-boilerplate-with-webpack.
I have some other project used only webpack with npm tasks.
And they both works totally fine. And I think it burns down to is how complicated your task is, and how much control you want to have in your configuration.
For example, if you tasks is simple, let's say dev, build, test ... etc ( which is very standard ), you are totally fine with just simple webpack with npm tasks.
But if you have very complicated workflow and you want to have more control of your configuration ( because it is coding ), you could go for gulp route.
But from my experience, webpack ecosystem provides more than enough plugins and loaders that I will need, and so I love using the bare minimum approach unless there is something you can only do in gulp. And also, it will make your configuration easier if you have one less thing in your system.
And a lot of times, nowadays, I see people actually replacing gulp and browsify all together with webpack alone.
The concepts of Gulp and Webpack are quite different. You tell Gulp how to put front-end code together step-by-step, but you tell Webpack what you want through a config file.
Here is a short article (5 min read) I wrote explaining my understanding of the differences: https://medium.com/#Maokai/compile-the-front-end-from-gulp-to-webpack-c45671ad87fe
Our company moved from Gulp to Webpack in the past year. Although it took some time, we figured out how to move all we did in Gulp to Webpack. So to us, everything we did in Gulp we can also do through Webpack, but not the other way around.
As of today, I'd suggest just use Webpack and avoid the mixture of Gulp and Webpack so you and your team do not need to learn and maintain both, especially because they are requiring very different mindsets.
Honestly I think the best is to use both.
Webpack for all javascript related.
Gulp for all css related.
I still have to find a decent solution for packaging css with webpack, and so far I am happy using gulp for css and webpack for javascript.
I also use npm scripts as #Tetradev as described. Especially since I am using Visual Studio, and while NPM Task runner is pretty reliable Webpack Task Runner is pretty buggy.

Is it possible to access npm config settings from a node package's `bin` command?

I want to add some default configuration into a shell tool that the user can override using npm config. It looks like this is possible but this only works for npm scripts not my package's binary as specified by "bin" below.
Package.json
{
"name": "tmp",
"scripts": {
"test": "node index.js"
},
"bin" : {
"tmp" : "index.js"
},
"config": {
"foo" : 123
}
}
index.js
#!/usr/bin/env node
console.log(process.env.npm_package_config_foo);
My attempts
calling binary
setup for this is running npm link in the package to make a global link to that package
$ tmp
undefined
passing script to node
$ node ./index.js
undefined
calling as npm script ⫸ only this one works
$ npm test
> tmp# test /private/tmp
> node index.js
123
Question
How can I access these config values in a way that's overridable by the user like npm config allows? (To be clear I want to do it the npm config way; I know there are other ways to skin this particular cat.)
You can use a package called npm-conf with documentation at https://github.com/kevva/npm-conf.
First you need to install it:
npm install --save npm-conf
Usage is as follows:
const npmConf = require('npm-conf');
const conf = npmConf();
conf.get('prefix')
//=> //=> /Users/unicorn/.npm-packages
conf.get('registry')
//=> https://registry.npmjs.org/
If you want to get a list of all available NPM configuration options:
npm config list -l

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