Yeoman Blender

Yeoman generator methods as mixins.

This module helps you organize your Yeoman generator code by splitting methods into multiple modules, aka mixins. You can write generator's prototype mixins (methods will run sequentially) or split methods by feature/option and priority upon the Yeoman queue system.

Installation

$ npm i yeoman-blender

Usage

# Move into your generator folder 
$ cd /path/to/your/yeoman/generator
 
# Create the "flavors" folder into the "app" or subgenerator folder 
$ mkdir app/flavors
 
# Split your generator features by flavor 
$ mkdir -p app/flavors/{css,ui}
 
# Create modules to organize methods by priority 
$ touch app/flavors/css/{initializing.js,prompting.js,writing.js}
$ touch app/flavors/ui/{initializing.js,prompting.js,writing.js}
 

Supported priorities are:

• initializing (example: app/flavors/css/initializing.js)
• prompting (example: app/flavors/css/prompting.js)
• configuring (example: app/flavors/css/configuring.js)
• writing (example: app/flavors/css/writing.js)
• install (example: app/flavors/css/install.js)
• end (example: app/flavors/css/end.js)

Write your generator methods inside these modules:

// generator/app/flavors/css/writing.js
module.exports = {
  css: function() {
    this.copy('main.css', 'css/main.css');
  }
};

You can also define generator's prototype methods:

// generator/app/helpers.js
module.exports = {
  sayHello: function() {
    this.log('Hello');
  }
};

Then in generator/app/index.js:

'use strict';
 
var path    = require('path');
var yeoman  = require('yeoman-generator');
var blender = require('yeoman-blender')();
 
// Add generator methods (order counts)
blender.methods([
  require('./path/to/generator/app/mixins')
]);
 
// Add flavor directories (order counts)
blender.flavors([
  path.join(__dirname, 'features', 'base'),
  path.join(__dirname, 'features', 'css'),
  path.join(__dirname, 'features', 'ui')
]);
 
// Then call blend() to get the global mixin
module.exports = yeoman.generators.Base.extend(blender.blend());

Example

Let's take an example. You need to write a generator that let the developer choose between several CSS preprocessors (SASS, Less, Stylus, etc) and several UI frameworks (Twitter Bootstrap, Foundation, SemanticUI, etc). Instead of having a big bloated generator file, you can split this generator into two "flavors" (or "features"): css and ui. You create a flavors folder into your app directory (or subgenerator) and one folder per flavor:

generator/app/index.js
generator/app/templates/
generator/app/flavors/css/
generator/app/flavors/css/initializing.js
generator/app/flavors/css/prompting.js
generator/app/flavors/css/configuring.js
generator/app/flavors/css/writing.js
generator/app/flavors/ui/
generator/app/flavors/ui/initializing.js
generator/app/flavors/ui/prompting.js
generator/app/flavors/ui/writing.js

As you can see, each flavor folder contains modules named with Yeoman queue names (or priorities). Each module exports a plain object with methods to invoke on that given queue:

// generator/app/flavors/css/writing.js
module.exports = {
  css: function() {
    this.copy('main.css', 'css/main.css');
  }
};

This module will be merged into the generator prototype like this:

{
  writing: {
    css: function() {
      this.copy('main.css', 'css/main.css');
    }
  }
}

Flavors help you write modular code.

You add flavors with the flavors() method that takes an array of paths:

blender.flavors([
  path.join(__dirname, 'flavors', 'base'),
  path.join(__dirname, 'flavors', 'css'),
  path.join(__dirname, 'flavors', 'ui')
]);

You can also add mixins that will be directly merged into the generator's prototype. This can be useful for initialization or to define common helpers. These mixins can be added with the methods() method that takes an array of mixins.

blender.methods([
  require('./lib/init.js'),
  require('./lib/helpers.js')
]);

Once you setup your methods and flavors, you just need to call blend() to retrieve the global mixin to give to Yeoman generator extend() method:

var Generator = yeoman.generators.Base.extend(blender.blend());

License

MIT License.