locreq

locreq is an answer to the problem of requiring local paths in Node.js. It allows you to easily require modules by specifying their paths relative to your project root, not relative to the file they're required from.

Assume the following directory structure:

- lib
  - collectionA
	- moduleA1.js
	- moduleA2.js
  - collectionB
	- collectionB1
	  - moduleB1a.js

Now, to require module A2.js from module B1a.js, using regular require:

require("../../collectionA/moduleA2.js");

There are a few problems with the above example:

• it has a high cognitive overhead;
• when you move the B1a.js file, you have to update the argument to require;
• it's hard to search for all files that require the A2 module.

With locreq, it's easier:

const locreq = require("locreq")(__dirname);
locreq("lib/collectionA/moduleA2.js");

If you have lots of dependencies, locreq can really make a difference.

Installation & usage

To install locreq, use:

npm install --save locreq

To use the module, require it like so:

const locreq = require("locreq")(__dirname);

The (__dirname); part is very important, don't forget it!

Next, simply use locreq instead of require for your local modules, giving a path relative to the root of your package (that is, relative to the directory where the package.json of your project is):

var moduleA = locreq("lib/my-modules/moduleA.js");

Similar to regular require, you can also use the locreq.resolve method:

const module_path = locreq.resolve("lib/my-modules/moduleA.js"); //returns the absolute path to the module

How does it work?

1. locreq goes up the directory hierarchy, parent directory by parent directory
2. Once it finds a package.json it stops the search and treats the directory as the root directory of the package
3. It then performs a regular require on a path that's resolved from combining the package root directory and the path given as an argument, and then returns that.

Advantages

• it works even if your package is required by a different package (which is not the case for the require.main.require trick);
• it doesn't mess with the global scope;
• it doesn't need changes in environment variables;
• it doesn't need any additional start-up scripts;
• it doesn't overwrite the default require behavior.