Exports and require scope in node.js

Question

fighting for 5 days with the problem. I have 3 files, needed to share one varible kvmIndex between them

getKvmIndex.js

var kvmIndex=[],
exports.kvmIndex = kvmIndex;
exports.getSNMP = function (callback) {
   async.each(switchIps, function(switchIp, callback1) {
   goGo(switchIp, callback1);
   }, function(err) {
        callback();
    })
};

match.js

var app1 = require("./app.js");
var kvmIndex;
exports.kvmIndex = kvmIndex;
...

exports.matchAll = function(callback) {
async.series([
    function(callback) {
        kvmIndex = app1.kvmIndex;
        decToHex(callback);
    },
    function(callback){
        matchSt('getPortToSt2', callback);
    },
    function(callback){
        console.log(kvmIndex);    //Here it defined! Works good.
        callback()
    }
])
callback();
}

app.js

var kvmSNMP = require('./getKvmIndex')
, match = require('./match')
, async = require('async')
, kvmIndex = [];
...
async.series([
function(callback) {
    kvmSNMP.getSNMP(callback);
},
function(callback) {
    exports.kvmIndex = kvmSNMP.kvmIndex;
    callback();
},
function(callback) {
    match.matchAll(callback);
},
function (callback) {
    kvmIndex = match.kvmIndex;
    callback();
},
function (callback) {
    console.log(match.kvmIndex); //Doesnt work(
    callback();
}
])

What i'm doing:

• Define blank variable
• Export it
• Doing stuff with it globally
• Accessing it in app.js

In getKvmIndex.js it works fine, but in match.js no. Can anybody help me?

Answer 1

You need to define kvmIndex in one module (file) and one only. It that module, add to it exports like you do. The other modules (files) need to require the module defining kvmIndex , and use it by accessing myModule.kvmIndex .

Notes:

1) It would be nicer to export getKvmIndex() from getKvmIndex.js , and not the variable kvmIndex directly.

2) You may have a bug in match.js -- the callback is called immediately. Did you maybe mean to pass callback and the 2nd argument to async.series() ?