如何在“使用严格”模式下跨多个节点模块将对象数组作为数据存储访问？

Question

So I am using an object array as my datastore. Every module is in 'use strict' mode so globals do not work. I tried creating aa single module to store my data and including it on several modules, however it fails to work.

list.js

'use strict';

module.exports.list = [];

I'll have other files access this, for example, the main code, and then a test file. I need to be able to access and manipulate the array from every file list is included. All i get is modules crashing.

code.js

var list = require('./list.js').list;
    list = [{id:1},{id:2},{id:3}];

Trying to run the specs, just crashes everything, removing the datastore makes tests fail.

code_spec.js --tests

var list = require('./list.js').list;
    fixtures = [{id:1},{id:2},{id:3}];
list = fixtures;

Answer 1

You aren't actually updating the singleton instance of list. You want to use a setter and a getter for this. You can use the concept of closures for this to access the local variable inside list.js.

//list.js

var list = [];

module.exports.get = function () {
    return list;
}

module.exports.set = function (ll) {
    if (Array.isArray(ll)) {
        list = ll
    }
}

and how to use it in your other file:

//other.js

var listService = require('./list');

list = listService.get();

newList = listService.set([{id:1}, {id:2}, {id:3}]);

console.log(listService.get()); //[{id:1}, {id:2}, {id:3}]

Another possiblity which I would only use for certain things is to use the global object:

global.list = [{id:1}, {id:2}, {id:3}];

this can be used throughout the app. But DON'T polute your global space.