amd-optimize

An AMD (RequireJS) optimizer that's stream-friendly. Made for gulp. (WIP)

Features

• Trace all dependencies of an AMD module
• Stream-friendly: Pipe in files and get an ordered stream of files out. No need for writing on disk in between.
• Support for precompilation of source files (ie. CoffeeScript)
• Wraps non-AMD dependencies
• Supply a custom loader for on-demand loading
• Leaves concatenation and minification to your preferred choice of modules
• gulp-sourcemaps support

Example

var gulp = require("gulp");
var amdOptimize = require("amd-optimize");

gulp.task("scripts:index", function () {

  return gulp.src("src/scripts/**/*.js")
    // Traces all modules and outputs them in the correct order.
    .pipe(amdOptimize("main"))
    .pipe(concat("index.js"))
    .pipe(gulp.dest("dist/scripts"));

});

Motivation

This aims to be an alternative to the powerful r.js optimizer, but made for a streaming environment like gulp. This implementation doesn't operate on the file system directly. So, there's no need for complicated setups when dealing with precompiled files. Also, this module only focuses on tracing modules and does not intend replace a full-fletched build system. Therefore, there might be tons of use cases where r.js is a better fit.

Installation

$ npm install amd-optimize

API

amdOptimize(moduleName, [options])

moduleName

Type: String

options.paths

paths : {
  "backbone" : "../bower_components/backbone/backbone",
  "jquery" : "../bower_components/jquery/jquery"
}

options.map

map : {
  // Replace underscore with lodash for the backbone module
  "backbone" : {
    "underscore" : "lodash"
  }
}

options.shim

shim : {
  // Shimmed export. Specify the variable name that is being exported.
  "three" : {
     exports : "THREE"
  },

  // Shimmed dependecies and export
  "three.color" : {
     deps : ["three"],
     exports : "THREE.ColorConverter"
  },

  // Shimmed dependencies
  "bootstrap" : ["jquery"]
}

options.configFile

Type: Stream or String

Supply a filepath (can be a glob) or a gulp stream to your config file that lists all your paths, shims and maps.

amdOptimize.src("index", {
  configFile : "src/scripts/require_config.js"
});

amdOptimize.src("index", {
  configFile : gulp.src("src/scripts/require_config.coffee").pipe(coffee())
});

options.findNestedDependencies

Type: Boolean
Default: false

If true it will trace require() dependencies inside of top-level require() or define() calls. Usually, these nested dependencies are considered dynamic or runtime calls, so it's disabled by default.

Would trace both router and controllers/home:

define("router", [], function () {
  return {
    "/home" : function () {
      require(["controllers/home"]);
    },
    ...
  }
})

options.baseUrl

options.exclude

options.include

options.wrapShim

Type: Boolean
Default: false

If true all files that you have declared a shim for and don't have a proper define() call will be wrapped in a define() call.

// Original
var test = "Test";

// Output
define("test", [], function () {
  var test = "Test";
  return test;
});

// Shim config
shim : {
  test : {
    exports : "test"
  }
}

options.loader

WIP. Subject to change.

amdOptimize.src(
  "index",
  loader : amdOptimize.loader(
    // Used for turning a moduleName into a filepath glob.
    function (moduleName) { return "src/scripts/" + moduleName + ".coffee" },
    // Returns a transform stream.
    function () { return coffee(); }
  )
)

amdOptimize.src(moduleName, options)

Same as amdOptimize(), but won't accept an input stream. Instead it will rely on loading the files by itself.

Algorithms

Resolving paths

Finding files

1. Check the input stream.
2. Look for files with the default loader and baseUrl.
3. Look for files with the custom loader and its transform streams.
4. Give up.

Recommended modules

• gulp-concat: Concat the output files. Because that's the whole point of module optimization, right?

var concat = require("gulp-concat");

gulp.src("src/scripts/**/*.js")
  .pipe(amdOptimize("index"))
  .pipe(concat("index.js"))
  .pipe(gulp.dest("dist"));

• gulp-uglify: Minify the output files.

var uglify = require("gulp-uglify");

gulp.src("src/scripts/**/*.js")
  .pipe(amdOptimize("index"))
  .pipe(concat("index.js"))
  .pipe(uglify())
  .pipe(gulp.dest("dist"));

• gulp-coffee: Precompile CoffeeScript source files. Or any other language that compiles to JS.

var coffee = require("gulp-coffee");

gulp.src("src/scripts/**/*.coffee")
  .pipe(coffee())
  .pipe(amdOptimize("index"))
  .pipe(concat("index.js"))
  .pipe(gulp.dest("dist"));

• gulp-if: Conditionally pipe files through a transform stream. Useful for CoffeeScript precompilation.

var gif = require("gulp-if");

gulp.src("src/scripts/**/*.{coffee,js}")
  .pipe(gif(function (file) { return path.extname(file) == ".coffee"; }, coffee()))
  .pipe(amdOptimize("index"))
  .pipe(concat("index.js"))
  .pipe(gulp.dest("dist"));

• event-stream, gulp-order: Add files before or after

var eventStream = require("event-stream");
var order = require("gulp-order");

eventStream.merge(
  gulp.src("bower_components/almond/almond.js"),
  gulp.src(amdOptimize("index"))
    .pipe(concat("index.js"))
)
  .pipe(order(["**/almond.js", "**/index.js"]))
  .pipe(concat("index.js"))
  .pipe(gulp.dest("dist"));

Current limitations

• No RequireJS plugins.
• No exclude or include configuration.
• No circular dependencies

Tests

1. Install npm dev dependencies npm install
2. Install gulp globally npm install -g gulp
3. Run gulp test

License

MIT © scalable minds 2014