Global package installation — JS: Setting up environment

Some Node.js packages are not just plug-in libraries, but rather complete programs. For example, there is a JavaScript utility called sloc which can count the number of lines of code in a project. This utility itself is not tied to JavaScript, it works with source files in many different languages.

Such utilities are not associated with a specific project or even JavaScript. The implication is that they can be used by anyone. For these cases, there is another way to install it in npm – global. Take a look at an example:

# Depending on how you install Node.js
# may need sudo at the beginning of the command
npm install -g sloc

The -g flag indicates that the package should be installed globally. You can run this command from anywhere on the file system. npm adds this package to a special directory accessible to all system users. You can find out its location with another npm command:

npm config ls -l

...
prefix = "/Users/tirion/.asdf/installs/nodejs/14.5.0/.npm"
...

After installation, the utility becomes available on the command line by a name specified in the project documentation, e.g., on GitHub. In the case of sloc, the name of the package is the same as the command name:

# Note the period after the sloc command
# It means the current directory needs to be analyzed
sloc .

---------- Result ------------

            Physical :  785627
              Source :  550712
             Comment :  138793
 Single-line comment :  31810
       Block comment :  107078
               Mixed :  6852
 Empty block comment :  2495
               Empty :  105469
               To Do :  385

Number of files read :  6018

----------------------------

Do it yourself

1. Install the sloc utility globally
2. Run it in the nodejs-package project to count lines of code
3. Run sloc in hexlet-js project, too, and compare the results of the analysis of both projects
4. As an experiment, try installing hexo.io, a blogging framework. On the main page of the project, there's some information on how to install and run it

Are there any more questions? Ask them in the Discussion section.

The Hexlet support team or other students will answer you.