How to share code between node.js apps?
I have several apps in node that all share a few Modules that I've written. These modules are not available via npm. I would like to be able to share freely between apps, but I don't want to copy directories around, nor rely on Git to do so. And I'm not really big on using symlinks to do this either.
I would like to arrange directories something like this:
app1 server.js node_modules (public modules from npm needed for app1) lib (my own modules specific to app1) app2 server.js node_modules (public modules from npm needed for app2) lib (my own modules specific to app2) shared_lib (my own modules that are used in both app1 and app2)
The problem I'm seeing is that the modules in shared_lib seem to get confused as to where to find the modules that will be in the node_modules directory of whichever app they are running in. At least I think that is the problem.
So....what is a good way to do this that avoids having duplicates of files? (note that I don't care about duplicates of things in node_modules, since those aren't my code, I don't check them into Git, etc)
I've got this working by having node_modules folders at different levels - node then automatically traverses upwards until it finds the module.
Note you don't have to publish to npm to have a module inside of node_modules - just use:
Inside each of your private package.json files - for your project I would have the following:
app1 server.js node_modules (public modules from npm needed for app1) (private modules locally needed for app1) app2 server.js node_modules (public modules from npm needed for app2) (private modules locally needed for app2) node_modules (public modules from npm needed for app1 & app2) (private modules locally for app1 & app2)
The point is node.js has a mechanism for dealing with this already and it's awesome. Just combine it with the 'private not on NPM' trick and you are good to go.
In short a:
From app A or B would cascade upwards until it found the module - regardless if it lived lower down or higher up. Indeed - this lets you hot-swap the location without changing any of the require(...) statements.
node.js module documentation