I have module A that uses a singleton pattern to create an object which needs to be shared.
A.js:
...
let instance = undefined;
module.exports {
 init: function () {
  if(!instance)
     instance = new Instance();
 },
 getSomeValue: function () {
   return instance.get();
 },
}; 
I've got two different modules B and C, where each depends on the same module A,
B.js
const { init, getSomeValue } = require('A');
function middleware1(req, res, next) {
  init();
  next();
}
module.export = middleware1; 
C.js
const { getSomeValue } = require('A');
function middleware2(req, res, next) {
  console.log(getSomeValue()); // throws undefined, can not recognise initialisation by B module
  next();
}
module.export = middleware2; 
main application:
...
app.use(middleware1());
app.use(middleware2());
...
but there are separate copies of that dependent module under the node_modules subdirectory of each of the two different modules.
I want to initialize instance once no matter from which library/module it is instantiated and want to share the object across all the libraries/modules using it under the same project.
How can I access the instance state that I want to share across the complete node project?