So i'm looking at requirejs. I can either install this package with npm install requirejs, or download it manually from the website. What's the difference? Are there tradeoffs to either one? Is npm install just a fancier way of manually installing? Thanks.
imagine you have 10 libraries in package.json, and you want to install all of them at once, you can just do "npm i" and it will take care of all, in just ~10sec. compare this with installing those 10 lib manually, it is indeed a good friend, to help you ease the process of downloading lib for you in no time.
Yes, npm install is just a fancier way to add package that help saving your precious time.
Base on the description here: npm install.
If the package has a package-lock, or an npm shrinkwrap file, or a yarn lock file, the installation of dependencies will be driven by that
Install the dependencies in the local node_modules folder.
In global mode (ie, with -g or --global appended to the command), it installs the current package context (ie, the current working directory) as a global package.
By default, npm install will install all modules listed as dependencies in package.json.
With the --production flag (or when the NODE_ENV environment variable is set to production), npm will not install modules listed in devDependencies. To install all modules listed in both dependencies and devDependencies when NODE_ENV environment variable is set to production, you can use --production=false.
Without a package manager like npm or yarn, it could take you a lot of time just for installing stuff. And while you are developing with node js, you'd have ton of things to install.
Every modern programming language has it's own package manager, so why you ever need to manually install them?
I have just started learning React, and Facebook helps in simplifying the initial setup by providing the following ready-made project.
If I have to install the skeleton project I have to type npx create-react-app my-app in command-line.
I was wondering why does the Facebook in Github have npx create-react-app my-app rather than npm create-react-app my-app?
Introducing npx: an npm package runner
NPM - Manages packages but doesn't make life easy executing any.NPX - A tool for executing Node packages.
NPX comes bundled with NPM version 5.2+
NPM by itself does not simply run any package. It doesn't run any package as a matter of fact. If you want to run a package using NPM, you must specify that package in your package.json file.
When executables are installed via NPM packages, NPM links to them:
local installs have "links" created at ./node_modules/.bin/ directory.
global installs have "links" created from the global bin/ directory (e.g. /usr/local/bin) on Linux or at %AppData%/npm on Windows.
Documentation you should read
NPM:
One might install a package locally on a certain project:
npm install some-package
Now let's say you want NodeJS to execute that package from the command line:
$ some-package
The above will fail. Only globally installed packages can be executed by typing their name only.
To fix this, and have it run, you must type the local path:
$ ./node_modules/.bin/some-package
You can technically run a locally installed package by editing your packages.json file and adding that package in the scripts section:
{
"name": "whatever",
"version": "1.0.0",
"scripts": {
"some-package": "some-package"
}
}
Then run the script using npm run-script (or npm run):
npm run some-package
NPX:
npx will check whether <command> exists in $PATH, or in the local project binaries, and execute it. So, for the above example, if you wish to execute the locally-installed package some-package all you need to do is type:
npx some-package
Another major advantage of npx is the ability to execute a package which wasn't previously installed:
$ npx create-react-app my-app
The above example will generate a react app boilerplate within the path the command had run in, and ensures that you always use the latest version of a generator or build tool without having to upgrade each time you’re about to use it.
Use-Case Example:
npx command may be helpful in the script section of a package.json file,
when it is unwanted to define a dependency which might not be commonly used or any other reason:
"scripts": {
"start": "npx gulp#3.9.1",
"serve": "npx http-server"
}
Call with: npm run serve
Related questions:
How to use package installed locally in node_modules?
NPM: how to source ./node_modules/.bin folder?
How do you run a js file using npm scripts?
npx is a npm package runner (x probably stands for eXecute). One common way to use npx is to download and run a package temporarily or for trials.
create-react-app is an npm package that is expected to be run only once in a project's lifecycle. Hence, it is preferred to use npx to install and run it in a single step.
As mentioned in the main page https://www.npmjs.com/package/npx, npx can run commands in the PATH or from node_modules/.bin by default.
Note:
With some digging, we can find that create-react-app points to a Javascript file (possibly to /usr/lib/node_modules/create-react-app/index.js on Linux systems) that is executed within the node environment. This is simply a global tool that does some checks. The actual setup is done by react-scripts, whose latest version is installed in the project. Refer https://github.com/facebook/create-react-app for more info.
NPM is a package manager, you can install node.js packages using NPM
NPX is a tool to execute node.js packages.
It doesn't matter whether you installed that package globally or locally. NPX will temporarily install it and run it. NPM also can run packages if you configure a package.json file and include it in the script section.
So remember this, if you want to check/run a node package quickly without installing locally or globally use NPX.
npM - Manager
npX - Execute - easy to remember
npm - Package manager for JavaScript, just like: pip (Python), Maven (Java), NuGet (.NET), Composer (PHP), RubyGems (Ruby), ...
npx - runs a command of a package without installing it explicitly.
Use cases:
You don't want to install packages neither globally nor locally.
You don't have permission to install it globally.
Just want to test some commands.
Sometime, you want to have a script command (generate, convert something, ...) in package.json to execute something without installing these packages as project's dependencies.
Syntax:
npx [options] [-p|--package <package>] <command> [command-arg]...
Package is optional:
npx -p uglify-js uglifyjs --output app.min.js app.js common.js
+----------------+ +--------------------------------------------+
package (optional) command, followed by arguments
For example:
Start a HTTP Server : npx http-server
Lint code : npx eslint ./src
# Run uglifyjs command in the package uglify-js
Minify JS : npx -p uglify-js uglifyjs -o app.min.js app.js common.js
Minify CSS : npx clean-css-cli -o style.min.css css/bootstrap.css style.css
Minify HTML : npx html-minifier index-2.html -o index.html --remove-comments --collapse-whitespace
Scan for open ports : npx evilscan 192.168.1.10 --port=10-9999
Cast video to Chromecast : npx castnow http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/ForBiggerFun.mp4
More about command:
https://docs.npmjs.com/files/package.json#bin
https://github.com/mishoo/UglifyJS2/blob/master/package.json#L17
NPX:
From https://www.futurehosting.com/blog/npx-makes-life-easier-for-node-developers-plus-node-vulnerability-news/:
Web developers can have dozens of projects on their development
machines, and each project has its own particular set of npm-installed
dependencies. A few years back, the usual advice for dealing with CLI
applications like Grunt or Gulp was to install them locally in each
project and also globally so they could easily be run from the command
line.
But installing globally caused as many problems as it solved. Projects
may depend on different versions of command line tools, and polluting
the operating system with lots of development-specific CLI tools isn’t
great either. Today, most developers prefer to install tools locally
and leave it at that.
Local versions of tools allow developers to pull projects from GitHub
without worrying about incompatibilities with globally installed
versions of tools. NPM can just install local versions and you’re good
to go. But project specific installations aren’t without their
problems: how do you run the right version of the tool without
specifying its exact location in the project or playing around with
aliases?
That’s the problem npx solves. A new tool included in NPM 5.2, npx is
a small utility that’s smart enough to run the right application when
it’s called from within a project.
If you wanted to run the project-local version of mocha, for example,
you can run npx mocha inside the project and it will do what you
expect.
A useful side benefit of npx is that it will automatically install npm
packages that aren’t already installed. So, as the tool’s creator Kat
Marchán points out, you can run npx benny-hill without having to deal
with Benny Hill polluting the global environment.
If you want to take npx for a spin, update to the most recent version
of npm.
Simple Definition:
npm - Javascript package manager
npx - Execute npm package binaries
Here's an example of NPX in action: npx cowsay hello
If you type that into your bash terminal you'll see the result. The benefit of this is that npx has temporarily installed cowsay. There is no package pollution since cowsay is not permanently installed. This is great for one off packages where you want to avoid package pollution.
As mentioned in other answers, npx is also very useful in cases where (with npm) the package needs to be installed then configured before running. E.g. instead of using npm to install and then configure the json.package file and then call the configured run command just use npx instead. A real example:
npx create-react-app my-app
NPM => Is a JS package manager.
NPX => Is a tool for executing Node packages and execute npm package binaries.
It is easy to remember:
-npm stands for MANAGER
-npx stands for EXECUTE
NPM: NPM stands for Node Package Manager and is the default package manager for Node.js. It was developed by Isaac Z. Schlueter and was originally released on January 12, 2010. It is entirely written in JavaScript. It consists of a command-line client npm which manages all node.js packages and modules. When node.js is installed, it is included in the installation.
npm run your-package-name
NPX is a tool that use to execute packages.
NPX is an acronym for Node Package Execute The NPX package comes with npm, so when you install npm above 5.2.0, NPX will be installed automatically.
It is an npm package runner that can execute any package that you want from the npm registry without even installing that package. The npx is useful during a single time use package. If you have installed npm below 5.2.0 then npx is not installed in your system.
Run the following command to determine if npx is installed:
npx -v
The following command can be run if npx is not installed.
npm install -g npx
Use npx to execute the package:
npx your-package-name
Simplest Definition:
NPX
The npx stands for Node Package Execute and it comes with the npm,
when you installed npm above 5.2.0 version then automatically npx will
installed. It is an npm package runner that can execute any package
that you want from the npm registry without even installing that
package.
NPM
npm is a package manager for the JavaScript programming language
maintained by npm, Inc. npm is the default package manager for the
JavaScript runtime environment Node.js. It consists of a command line
client, also called npm, and an online database of public and paid-for
private packages
NPM vs. NPX
NPM stands for the Node Package Manager. A text based program for Nodejs package management.
While NPX is a Node Package Runner. Its function is to execute the Nodejs package
NPX will execute binary files from the Nodejs package, both installed and not.
Even NPX can also help us use certain versions of Nodejs without having to use nvm (node.js version management), nave (node.js virtual environment), and nvm (node.js version management).
NPM stands for Node Package Manager. NPM is Node.JS's default package manager. It's written in Javascript. The role of NPM is to manage the package and modules of node.js.
NPX stands for Node Package Execute. NPX comes with npm, when npm is installed above the 5.2.0 version, it gets installed automatically. NPX is an npm package runner and its role is to execute the package from the registry without even installing that package.
Now, the differences between NPM and NPX are as below:
i) NPM is used to install the packages while NPX is used to execute the packages.
ii) Due to npm the packages installed have to be taken care of since it's installed globally while the packages which are used by npx don't need to be taken care of as they are not installed globally.
Simple answer is like
NPX: is used to execute any node package without installing the package on our machine.
NPM: is used to install any node js package in our machine. We can use "require("package-name')" when we install any package using NPM. but we can not import the package when we use NPX.
Example: You should run npm i axios
in this case you are installing axios package in your local machine
and npx create-react-app 'app-name'
here you are executing the create-react-app package directly on your machine without installing it's files.
NPM stands for Node Package Manager.
It comes pre-installed with Node.js. NPM helps to manage packages in your projects as dependencies.
When using NPM, there are two ways to install a package into your local computer.
Locally: When a package is installed locally, it is installed in
./node_modules/.bin/ of the local project directory.
Globally: A global package is installed in the user environment
path. /usr/local/bin for Linux and AppData%/npm for Windows.
To execute a locally installed package, it should be specified in the package.json scripts block as shown below.
"scripts": {
"your-package": "your-package-name"
}
Then, you can execute the package with:
npm run your-package-name
NPX is an NPM package executor.
Currently, NPX is bundled with NPM when you install the NPM version 5.2.0 or higher.
Why NPX over NPM?
No need to edit the package.json file with node_modules paths.
You can directly execute the tool from the command line.
The differences between NPM and NPX are as below:
i) NPM is used to install the packages while NPX is used to execute the packages.
ii) Due to npm the packages installed have to be taken care of since it's installed globally while the packages used by npx don't need to be taken care of as they are not installed globally.
NPX is a tool for creating and executing some features in a new project
NPM is the package manager that contains all of libraries
Here is the simple definition.
NPM is a package manager, you can install node.js packages using NPM
NPX is a tool to execute node.js packages.
Here's an example of what your app creation might look like using npx
npx create-react-app project-name --template all
Simply npm is the Node Package Manager and
npx is the executeable version that run npm packages
npm is a tool that use to install packages and npx is a tool that use to execute packages.
npm-If you wish to run package through npm then you have to specify that package in your package.json and install it locally.
npx-A package can be executable without installing the package. It is an npm package runner so if any packages aren’t already installed it will install them automatically.
npm - package manager
npx - Execute npm package
This is a difference with it.
npm is package manager or installer on the other hand Packages used by npx are not installed globally so you have to carefree for the pollution for the long term.
Actually, I tried many ways to solve this and failed but finally removing/deleting yarn globally solves the problem
just type this command in your commandline terminal:
npm uninstall -g yarn
And then run the command below to install the react starter project
npx create-react-app
I've been developing a later-to-be-release Open Source project with Node as a CLI tool. The CLI itself works great I only need to test if it works while on another project, so for that I installed the projects globally npm install -g without errors, but for the life of me I can't use the CLI.
I get the following error:
The odd thing is that the directory and file does exist in the global npm folder:
This is the project's package.json:
Am I not understanding how making a npm/node CLI works? What I'm missing?
EDIT 1:
This is my index.js file:
And this is the commander.js file:
EDIT 2:
After creating a test project as #AngYC suggested I could use the test cli successfully, while inspecting the difference I found this. Inside C:\Users\Ivan\AppData\Roaming\npm the .cmd of both projects are quite different:
EDIT 3 (Solution):
After fiddling around I found out that the file that really needed the shebang (#!/usr/bin/env node) was only index.js file and not the commander.js one. Removing the shebang in that file solved the problem
You may want to try to link your local package to your global executable list.
https://docs.npmjs.com/cli/link
All you have to do is run npm link in the folder you got your tool and it should make the command available globally.
Try to uninstall cli run npm rm -g cli or sudo npm rm -g cli. Then you run: npm install cli -g
If the problem persist, you might want to remove you npm package globally, probably there might be some conflicting things running.
Type this: %appdata% (either in explorer, run prompt, or start menu).
You can simply remove all globally installed npm packages by deleting the contents of:
C:\Users\username\AppData\Roaming\npm
Then you might also want to clear all the your cache run npm cache clear or npm cache clear --force as the case might be.
Then you reinstall all your packages that were install globally again.
If problem still persist, check this:
When you run npm root -g, it yields C:\Users\<username>\AppData\Roaming\npm\node_modules, or even, you should check your path maybe the executable binaries and .cmd files end up in C:\Users\<username>\AppData\Roaming\npm instead of C:\Users\<username>\AppData\Roaming\npm\node_modules, you will need to add that path to the PATH env. variable.
I hope this resolves your issue.
I can not run the Angular 2 project.
What I tried:
- running the project by using npm install and npm start | does not work
- I cloned quickstart from the github and replaced with my src folder and I still get the "can not find module in #angular/core"
Here is the full console output: https://www.dropbox.com/s/5plmqrjd6ge0lta/error.txt?dl=0
Many people will come here. I have had the same problem. Do not panic. You are probaly following the tutorial of tutorialspoint.
Just install the core again using NPM
npm install #angular/core
There was/is a bug in certain versions of npm that causes installed modules to disappear when using npm install someModule ... or npm install someModule --save-dev
This was apparently an issue if the module being installed was from a GitHub repo and lacked a specific commit hash to reference for the installation. Although the issue was marked "closed" and the repo archived several months ago at v5.6.0, I ran into the problem today w/the latest npm 6.4.0
In my case, doing npm install rxjs completely removed the #angular/core module, along with my #ionic-native plugins, and anything else I'd installed individually (and then it failed to actually/properly install rxjs anyway!!)
Tip: copy your existing npm modules folder as a backup before starting updates or removing it entirely & trying to npm install.
You can manually install to your project via npm install #angular/core, but depending on the npm version (or the angle of the moon at that precise moment, who knows) be aware that you might wind up with other missing dependencies.
Also try npm install #angular/core && npm install ... Apparently the additional npm install helps replace the randomly deleted/missing modules in some cases.
Does npm install only install packages in the directory you run it from? Because that's my current experience with it. At first, I ran npm install xml in a command prompt at C:/Users/ME. Running require("xml"); in a node instance that was run from C:/Users/ME works, and running npm ls lists the xml package...
But if I move to any other directory, neither of them do.
Is this the expected behavior (doesn't sound right), a Windows thing, or am I missing some kind of install option?
Yes, this is normal behavior.
npm install (in package directory, no arguments):
Install the dependencies in the local node_modules folder.
In global mode (ie, with -g or --global appended to the command), it
installs the current package context (ie, the current working
directory) as a global package.
By default, npm install will install all modules listed as
dependencies. With the --production flag (or when the NODE_ENV
environment variable is set to production), npm will not install
modules listed in devDependencies.
NPM Install Docs
npm installs modules either below the current directory (in a node_modules sub-directory) or if you use the -g flag when running it, it install modules in the global location which is determined via OS and configuration and then node.js will be able to find the module no matter where it is being loaded from.
So, this will install a module globally:
npm install -g xml
When using require(), if you want require to look in the current directory to load a module, then you have to do it like require("./module");, otherwise it will not look for the modules install in the current directory.
You need to do npm install -g xml. This would install the packages globally.
'-g' represents global. Then when you check on other directories, you could list the same package
Note the way you install node is important as well!
You can install node with:
chocolatey (https://chocolatey.org/packages?q=nodejs)
nodeJS website (https://nodejs.org/)
*Knowing where to set your user variables is essential know how for windows developers! The reason I mention this is that the list of chocolatey, and node USER : PATH variables gets so large at one point nodejs and with it npm will just stop working. You need to work within your env. variables in one scenario where that happens. (Can typically happen with multiple versions of SQL Server installed)
If you want an excellent free, offline-available resource on node and npm I suggest devdocs (http://www.devdocs.io) and as well GentlNode's cheat sheets (https://gentlenode.com/journal/cheatsheet) *GentleNode not avail. offline FYI.
There's some key information you haven't received yet. See below:
npm install xml - installs "xml" package and required modules to the local folder you are in when you run the command. Files exist for you to work on in this folder alone(and thus commands only work in this folder) and "xml" cannot be called in cmd/terminal outside of this folder(without rerunning with "-g" param) "xml" is NOT written to package.json file. When and if project is uploaded to github will upload in full if you don't add node_modules to your .gitignore file.
npm install -g xml - install "xml" to your global npm folder, which is referenced to your "user environment variables" (what allows you to call specific functions, methods, and executables from within the command line) Files are NOT installed to your project folder, not recorded in "package.json" file. Will NOT upload anything to github.
npm install --save xml - using "--save" allows you to "install" to this folder, but also to write the package you've included into your project's "package.json" file. Here, your aim is to distribute your software and you want as little files on github/source control as possible that npm knows how to install like jQuery, XML, body-parser, etc. etc.
You would typically use a regular "npm install XML" command for a lightweight, rapid release mini-tool to support a key feature or process improvement you just want to keep on your local machine. In addition, you could npm install "packages" to a folder, and use that as a backup "node folder" mapped to your environment variables.
You would typically use a global "npm install -g XML" command for something like middleware, express, node updates installed VIA npm, and other processes you wish to have access to in cmd/terminal from "anywhere." Once this is established for your core development packages in node, you often just use the proceeding command, read the explanation for more detail.
Lastly, you would use "npm install --save" to write into the "package.json" file the required module(s) you've installed to your project. This would be for those who have worked heavily in node and have used "npm install -g" to already globally install their most common core nodeJS. This will write to the package.json the packages and versions being leveraged in your software currently so that your end-user can download the lightweight version and use npm package management to install all of the module dependencies so the app works correctly on other people's computers.
*Note, this leads to the last command "npm install" which you can run in a given folder where you've downloaded the file directly from github.
Hope that helps a bit more for the given facets of installation using npm!