将选项传递到节点模块以供导出功能使用

Question

I am creating a node module and want the end user of this module to be able to pass it configuration options that will have an effect on the modules functions.

For example, with express you can create an express app and pass it to your routes as such:

const express = require('express');
const app = express();

require('./api/routes/login)(app)

and then in your routes file you can use that app -> /api/routes/login

//login.js

  module.exports = function(app){

   app.get('/login', function(req, res){//blah}

  }

So what I am trying to do in my module is something similar in which an end user can pass an optional config parameters for the module's functions to use. This is was I was trying.....

In my module file:

const default_options = {"enabled":true}
module.exports = function(options) {
const options = options || default_options

exports.login = function(credentials) {
if(options.enabled == true){
 //do something
 }else{
    //do something else
  }
 }

}

And then someone using the module would be able to do something like this:

//some js file
 var options = {"enabled":false}
 const mod = require('mymodule')(options)

 mod.login(creds)

The error I am getting is 'Cannot read property 'login' of undefined'. I suspect it has something to do with me using exports twice but trying to figure out how to structure my module's js file to be able to use these options if passed it and apply them to the exposed functions.

Any help is appreciated, thank you!

Answer 1

You need to return an object from the exported function.

const default_options = {"enabled":true}
module.exports = function(options) {
    const options = options || default_options
    return {
        login: function(credentials) {
            ...
        }
    }
}