Require modules from highest (i.e. loading) module.
It is based hugely on parent-require, but it loads declaration highest in the project hierarchy. That is useful when you have for instance module that require module that require module which populate Mongoose models you want to use in your project.
Most of code/documentation is copy from parent-require.
$ npm install top-require
top-require addresses an annoying error condition that arises when
developing plugins, which have peer dependencies,
that are npm link'd into an application.
The problem is best illustrated by example. We'll use a shared package of Mongoose schemas, but the concept applies equally well to any module you plugin to a larger framework.
Let's develop a set of shared Mongoose schemas for a
user database, packaged as mongoose-schemas-users for reuse by any application
that needs to query the database.
var mongoose = require('mongoose');
var UserSchema = new mongoose.Schema(...);
module.exports = UserSchema;The important bit here is that mongoose is a peer dependency of this
package.
Now, let's install this package...
npm install mongoose-schemas-users
..and require it within our application:
var mongoose = require('mongoose')
, schemas = require('mongoose-schemas-users')
mongoose.model('User', schemas.UserSchema);So far, so good.
During the course of developing the application, we discover that we need to tweak the schemas we've defined. This is usually easy:
npm link mongoose-schemas-users
We've made some edits, and run the application:
Error: Cannot find module 'mongoose'
WTF?!? This issue arises because mongoose is a peer dependency. Now that
it has been npm link'd to a directory that resides outside of the application
itself, Node's typical resolution algorithm fails to find it.
This is where top-require comes into play. It provides a fallback to
require modules from the loading (aka parent) module. Because the loading
module exists within the application itself, Node's resolution algorithm will
correctly find our peer dependency.
try {
var mongoose = require('mongoose');
} catch (_) {
// workaround when `npm link`'ed for development
var prequire = require('top-require')
, mongoose = prequire('mongoose');
}
var UserSchema = new mongoose.Schema(...);
module.exports = UserSchema;With the fallback in place, we can both npm install and npm link this
plugin, correctly resolving peer dependencies in both cases.
$ npm install
$ npm test
- Creator of original Parent Require Jared Hanson
- Lukasz Sielski
Copyright (c) 2014 Lukasz Sielski <http://lukaszsielski.pl/> Copyright (c) 2013 Jared Hanson <http://jaredhanson.net/>