CODEWITHSUNDEEP
javascriptnode.jsexpress
David Jones
David Jones

Reputation: 4305

Node / Express, including custom modules

I am currently using Express with node and I am running into an issue when trying to use a custom module from inside one of my route functions. Here is what I have so far.

In my app.js file I require the module like so.

c_controller = require( './core/c_controller' );

I know this is required correctly because I console logged it out and it shows up fine.

The c_controller module looks like this.

var c_controller = {

styles: [],
script: '',
view: ''
};

c_controller.add_style = function( style ) {

    this.styles.push( style );

    return this;
},

c_controller.set_script = function( script ) {

    this.script = script;

    return this;
},

c_controller.set_view = function( view ) {

    this.view = view;

    return this;
},

c_controller.render = function() {

    return { script: this.script,
             styles: this.styles,
             view: this.view };
}

exports.add_style = c_controller.add_style;
exports.set_script = c_controller.set_script;
exports.set_view = c_controller.set_view;
exports.render = c_controller.render;

The error that appears is 500 ReferenceError: c_controller is not defined.

Now im not sure if I have to pass the c_controller object into my route functions, either way im not sure how to do this.

I anyone could explain this to me to make it clearer that would be great.

Thanks in advance.

UPDATE

Here is the code that uses the c_controller

/*
 * GET home page.
 */
exports.index = function(req, res){

    c_controller.set_view( 'index' );

    res.render( 'includes/overall_template', { c_controller.render() } );
};

Now if I require the c_controller directly into the route it works. I would rather only require the module in the main app file so I will not have to do this in every route. Does anyone know if this is possible??

Upvotes: 0

Views: 553

Answers (2)

Nitzan Shaked
Nitzan Shaked

Reputation: 13598

To try and summarize all the comments, and what you yourself @DavidJones said:

  1. From within your custom view, c_controller is not known. You would have to either require it in the view's module or even in the view function itself. You could also pass it to the view class, but I that complicates thing, and much prefer requiring.

  2. What @Linus said -- think about exporting your whole object (not just the function), or use bind otherwise.

Upvotes: 0

Linus Unnebäck
Linus Unnebäck

Reputation: 24291

Since you use this inside your functions in c_controller and you then assign only the functions to the export object, your functions will reference export when you write this and not c_controller.

I think the best way to fix it is to export the entire c_controller object, like this:

module.exports = exports = c_controller;

If you want the styles, script and view variables hidden you can either:

  1. Use c_controller instead of this
  2. Bind the functions before exporting them, like so: exports.add_style = c_controller.add_style.bind(c_controller)

Upvotes: 1

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