Skip to main content

NodeJS

npm Commands​

This command will install the package-name & add to the package.json

npm install package-name

This command will install the latest version of given package-name

npm install package-name@latest

This command will install the specific version of given package-name

npm install package-name@version
npm install jest@18.1.0

This command will remove or uninstall the package-name from node_modules & package.json

npm uninstall package-name

This command is to get a list of all available npm commands.

npm help

This command will print all top-level installed packages and their dependencies in a tree structure.

npm list

This command will show all the information about the given package-name

npm show package-name

This command will show all outdated packages in the current folder.

npm outdated

This command will show all globally installed outdated packages.

npm outdated -g

This command will update the outdated packages in the current folder

npm update

This command will update the globally installed outdated packages

npm update -g

This command will update the specific packages in the current folder

npm update jest

npm run scripts​

This command will provide information on how npm handles the "scripts" field

npm help npm-scripts

Aliases​

npm uses a number of aliases for common commands:

i is an alias for install

un is an alias for uninstall

up is an alias for update

ls is an alias for list

Package.JSON​

Run the command npm init to create the file while answering some questions about your project.

Run the command npm init -y to create the file with default values without a need to answer any question.

This file:

  • Contains meta-data about your project
  • Manages dependencies of your project
  • Contains scripts that help in generating builds, running tests and some other stuff

All package.json requires:

  • "name" - It must be all in lower case and contain no spaces
  • "version" - This uses semantic versioning.

Run the command npm install to install dependencies from an existing project using Package.JSON

Adding dependencies to Package.JSON

npm install packagename --save //install as devDependency

Note: As of npm 5.0.0, installed modules are added as a dependency by default, so the --save option is no longer needed.

npm install -D packagename //install as a dependency
npm help install //to check the help for npm install command

Installing npm packages locally or globally

npm install packagename //installs locally. The command will be available to run from the folder where it is installed.

npm install -g packagename //installs globally.The command will be available to run from anywhere.

npm packages can be installed locally or globally.

Package-lock.JSON​

  • Automatically generated for any operations where npm modifies either the node_modules tree or package.json.
  • As the package-lock specifies a version, location and integrity hash for every module and each of its dependencies, the install it creates will be the same, every single time.

References:

https://medium.com/beginners-guide-to-mobile-web-development/why-package-json-npm-basics-cab3e8cd150

https://medium.com/coinmonks/everything-you-wanted-to-know-about-package-lock-json-b81911aa8ab8

Semantic Versioning (SemVer)​

Major.Minor.Patch (4.5.0)

  • Major: Breaking Changes
  • Minor: Backward Compatible
  • Patch: Bug Fixes

Symbols used in SemVer:

~ means update can install the most recent patch version (e.g. ~4.5.0) - matches any 4.5.x version.

^ means update can install most recent minor version (e.g. ^4.5.0) - matches any 4.x.y version.

Common Issues​

Issue:

Error: Cannot find module '../lib/utils/unsupported.js'

Solution:

Uninstall node: brew uninstall --force node

Install it again: brew install node

If the above solution doesn't work, check out: https://gist.github.com/DanHerbert/9520689

OR run brew uninstall --force node then visit https://nodejs.org/en/ and download the LTS version and install and the error will be gone.

Issue:

npm throws error while trying to install any package globally without using sudo

Solution:

Check out:

https://www.competa.com/blog/how-to-run-npm-without-sudo/

https://www.competa.com/blog/use-nvm-for-fun-and-profit-and-to-run-npm-without-sudo/