Installing Current And Previous Packages Via NPM
When coming from Java/CFML to Node.js one of the first tools you come across is the package manager. This allows you to download/add packages globally to your environment or locally to your project (locally is the default way).
How to locally install a package
If you had a single project that used Coffee Script you should change your current directory to your application root directory and run
$ npm install coffee-script. This will grab you the latest copy, create a node_modules directory, only if it doesn’t already exist, and install the coffe-script module within it.
How to globally install a package
You might want to use coffee-script for all your projects. At which point you add the
-g flag, so your command becomes
$ npm install -g coffee-script. This will put the package in /usr/local/lib/node_modules.
Installing a previous version
When you start development you could be using version 1.82 of a package but in a couple of months when you bring on another developer they could be on v2.01 which breaks your app. To get around this you can choose which version of a specific module to install by using
$ npm install [package name]@[version]. So your new developer would use
$ npm install [package name]@1.82.
If the v1 branch is still maintained for bugs etc you can change your call using a wild card to get the latest version by using any of the following
$ npm install [package name]@1.x
$ npm install [package name]@1.8x
$ npm install [package name]@<2.0
You can take this further (though I haven't found a need for this yet) by defining the versions like this:
`$ npm install [package name]@">=1.82 <2.0"
Updating or uninstalling a package
As easy as it is to install you can update or uninstall a package either locally or globally
$ npm update -g [package name]
$ npm update [package name]
$ npm uninstall -g [package name]
$ npm uninstall [package name]