Includer

Concatenate JavaScript files with inline include statements.

Introduction

When writing an application, it is a good idea to keep source files separate for easier maintenance. However, when deploying an application, it's better to combine those files for fewer http requests.

Concatenation is a fairly simple problem, but what to concatenate where is a little trickier. When files require that other files proceed them, it becomes necessary to explicitly describe the concatenation order.

Maintaining a list of files in a build task or a config file is error prone and cumbersome. The heirarchy of which files depend on which other files must be maintained in the developer's head, and distract from development.

Rather than using external lists for concatenating files, Includer uses in-file include statements.

Installation

npm install includer --save-dev

Example

Suppose we want to concatenate these files together.

// app.js                    pages/home.js              pages/about.js
   var App = new Site();     App.home = new Page();     App.about = new Page();
   include('./pages/*');
   App.start();

When app.js is run through Includer, it will output the following.

(function(){
    var App = new Site();
    (function(){
        App.home = new Page();
    })();
    (function(){
        App.about = new Page();
    })();
    App.start();
})();

Usage

includer(filepath, [options], callback)

var includer = require('includer');
 
// options is optional
includer('path/to/entry.js', options, function (err, data) {
    // data is the concatenated and included file contents.
    // err is an Error object or null.
});

Include Syntax

include('./a.js');  // Paths are relative to the current file.
include('b.js');    // This is equivalent './b.js'.
include('./c');     // If no extension is found, '.js' will be used.
include("./d.js");  // Single or double quotes are supported.
include('../e.js'); // Upwards directory traversal is supported.
include('./f');
include('./f.js');  // Duplicates will only be included once.
include('./*.js');  // node-glob patterns are supported.

Options

separator

includer(filepath, {
    separator : '\n\n\n'
}, cb);

By default, all files are joined together by a \n. To change this, use the seperator option.

wrap

includer(filepath, {
    wrap : function (src) {
        return '(function(){' + src + '})()';
    }
}, cb);

Includer will wrap all files in an IIFE by default. To change the wrapping for files, use the wrap option.

The wrap option method will be called with the file's included contents as the only argument. It should return a string with the wrapped file contents.

To not wrap files, simply return the file's included contents as is.

includer(filepath, {
    wrap : function (src) {
        return src;
    }
}, cb);

debug

includer(filepath, {
    debug : true
}, cb);

Sometimes included globs have no matches. Includer will skip these globs silently.

If the debug option is true, a notification will be logged to the console when globs have no matches.

If the debug option is a function, it will be called with the debug message as the only parameter.

includer(filepath, {
    debug : function (message) {
        logs.push(message);
    }
}, cb);

paths

By default, all include() paths are relative to the current file.

However, relative paths become unwieldy when files are far apart.

include('../../../../../../scripts/src/config/file.js');

With the paths option, you can specify path mappings. These mappings are relative to the current working directory.

includer(filepath, {
    paths : {
        config : 'scripts/src/config'
        vendor : 'vendor/libs/js'
    }
}, cb);

To use the path mappings, prefix an include() with @ and the mapping name.

include('@config/file.js');   // CWD/scripts/src/config/file.js
include('@vendor/jquery.js'); // CWD/vendor/libs/js/jquery.js

A @base mapping to the current working directory is provided for free.

include('@base/file.js'); // CWD/file.js

Alternatives

For other tools that are tackling the same problem in different ways, see r.js, browserify, and grunt-neuter.

Credits

Includer was inspired by grunt-neuter.

Changelog

See the changelog

License

MIT License