Installing
Assuming you’ve already installed Node.js, create a directory to hold your application, and make that your working directory.
$ mkdir myapp
$ cd myapp
Use the npm init
command to create a
package.json
file for your application. For more
information on how package.json
works, see
Specifics of npm’s package.json handling.
$ npm init
This command prompts you for a number of things, such as the name and version of your application. For now, you can simply hit RETURN to accept the defaults for most of them, with the following exception:
entry point: (index.js)
Enter app.js
, or whatever you want the name of the
main file to be. If you want it to be index.js
, hit
RETURN to accept the suggested default file name.
Now install Express in the myapp
directory and save
it in the dependencies list. For example:
$ npm install express --save
To install Express temporarily and not add it to the dependencies list:
$ npm install express --no-save
By default with version npm 5.0+ npm install adds the module to
the dependencies
list in the
package.json
file; with earlier versions of npm,
you must specify the --save
option explicitly.
Then, afterwards, running npm install
in the app
directory will automatically install modules in the dependencies
list.