从node.js中的模块获取“随机”值

Question

Let's say I have a file that looks like this:

var random_nr = Math.floor(Math.random()*array.length);
var x = array[random_nr];
// do some things

exports.random_array_member = x

Now, if I 'require' this in another file, I will always get the same result as long as I don't restart my server, presumably because of caching?

What is the best way to run this code and get a random value, while not including the code into my main file?

Answer 1

The code you have shown is only executed once . The result from that code is then stored as a variable, ready to be exported to whatever file needs it.

Instead, you need to "call" the code at the moment you need a random variable:

exports.random_array_member = function(){
    var random_nr = Math.floor(Math.random()*array.length);
    return array[random_nr];
}

Now, instead of accessing exports.random_array_member , you call exports.random_array_member() in your other files.

Answer 2

Lets play with getters

random.js

var array = [1, 2, 3, 4, 5];

module.exports = {
  get random_array_member() {
    return array[Math.floor(Math.random()*array.length)]
  }
}

consumer.js

var r = require('./random')

console.log(r.random_array_member)
console.log(r.random_array_member)
console.log(r.random_array_member)