How do I load a node module as if the current module were located somewhere else?

Question

I have some nodejs code running in a module somewhere. From this module, I would like to load a module located in a completely different place in the file system -- for example, given the path "/another/dir" and the module name "foo", I would like Node to act as if a module running in /another/dir had called require("foo"), rather than my own module.

  My code is running here
/some/folder/node_modules/mine/my_module.js

  I have the path "/another/dir/", the string "foo",
    and want to load this module
/another/dir/node_modules/foo/index.js

In other words, the module documentation refers to the process "require(X) from module at path Y", and I would like to specify my own value for Y

Can this be accomplished? If so, how? If not, why not?

Answer 1

The simplest, is just to resolve the path into an absolute path, this will be the recommended approach for most if not all cases.

var path = require('path');

var basedir = '/another/dir';
var filename = 'foo'; // renamed from dirname

var filepath = path.join(basedir, 'node_modules', filename);
var imports = require(filepath);

If you really need to make require act as if it is in a different directory, you can push the base directory to module.paths

module.paths.unshift('/another/dir/node_modules');

var imports = require('foo');

module.paths.shift();

module.paths can also be modified externally via the environment variable NODE_PATH, tho that would be the least recommended approach but this does apply it globally across all modules.