Commonly Used npm Flags

#webdev #programming #javascript #beginners

-g (global)

Cmd: npm install -g <package-name>
Usage: Installs the package globally on your system, making it available from any directory. This is useful for tools and utilities you want to use across different projects.
Example: npm install -g create-react-app allows you to use the create-react-app command from anywhere on your machine.

-p (prefix)

Cmd: npm install -p <directory> <package-name>
Usage: Installs the package to a specific directory rather than the default node_modules in the current project. This can be used to manage packages for different environments or users.
Example: npm install -p /usr/local <package-name> installs the package to /usr/local.

-d (save-dev)

Cmd: npm install -D <package-name> or npm install --save-dev <package-name>
Usage: Adds the package as a development dependency. Development dependencies are only needed during development and testing, not in production.
Example: npm install -D jest adds jest to your devDependencies in package.json

{
  "dependencies": {
    "express": "^4.17.1"
  },
  "devDependencies": {
    "jest": "^27.0.6"
  }
}

Other Common npm Flags

--save(-S)

Cmd: npm install -S <package-name> or npm install <package-name>
Usage: Adds the package as a dependency in your package.json. This is the default behavior when you run npm install <package-name>
Example: npm install express will add express to the dependencies in package.json

--save-optional (-O)

Cmd: npm install -O <package-name>
Usage: Adds the package as an optional dependency. These dependencies are not critical for the project to function but can add optional features.
Example: npm install -O fsevents adds fsevents to optionalDependencies.

--save-exact (-E)

Cmd: npm install -E <package-name>
Usage: Installs the exact version specified without updating to newer versions.
Example: npm install -E lodash installs the exact version listed, e.g., lodash@4.17.21

--production

Cmd: npm install --production
Usage: Installs only the dependencies listed under dependencies and skips devDependencies. Useful for deployment.
Example: npm install --production ensures only necessary packages for running the app are installed.

Summary