yoga

yoga is a prompt-driven scaffolding system (boilerplate/starter-code generation). Its aim is to make it easier to create and maintain personal boilerplates that evolve over time.

What makes yoga different?

• 100% driven by command-line prompts (via Inquirer).
• The logic of copying files is in the filenames themselves, e.g. {isGulp}gulpfile.js or {useSass}main.scss.
• Files are templated using ejs, extended with additional whitespace-friendly syntax for better readability (via striate).

(see How it works below for details)

Generators created by yoga are yeoman generators, so they can be published and consumed them like any other yeoman generator. You do not need to understand yeoman to use yoga, however, and you do not need to write any code to create and maintain your generator.

Usage

1. Create your generator

yoga requires npm, which comes with node.

Your initial generator is itself generated by yoga. You only need to do this once.

$ npm install -g yo                 # install yeoman
$ npm install -g generator-yoga     # install yoga
$ mkdir mygenerator                 # create a directory for your new generator
$ cd mygenerator                    
$ yo yoga                           # generate your personal generator
$ npm link                          # alias your generator to your globally
                                    # installed npm modules so that you can run
                                    # it with yeoman.

2. Generate projects to your heart's content

Yay! Now you can run yo mygenerator in an empty directory to generate a new project.

$ yo mygenerator
? Does your project use Javascript? Yes
? Does your project use css? Yes
...

An initial yoga generator just consists of a blank README, so you have to customize it to generate something useful.

Customizing your generator

You can customize your yoga generator without writing any generator code:

• Drop files into app/templates. All files from this directory will be copied into your project directory when you run the generator.
• Edit the Inquirer prompts in app/yoga.json. These will determine which files get copied (via prefixnotes) and what code gets copied (via striate).

For example, if you have a prompt in your yoga.json that inquires about Javascript being included in the project:

{
  prompts: [{
    "type": "confirm",
    "name": "js",
    "message": "Does your project use Javascript?",
    "store": true
  }]
}

And a file in app/templates which specifies the prompt name in a prefixnote:

.
└── {js}main.js

Then when you run yo mygenerator, you will be prompted Does your project use Javascript?. If you choose yes, main.js will be copied into the project directory. If you choose no, it will not be copied.

Check out generator-yoga-sample for an example yoga generator.

More detailed usage

Inquirer prompts drive everything in a yoga generator.

Sample yoga.json file:

{
  "prompts": [
    {
      "type": "confirm",
      "name": "js",
      "message": "Does your project use Javascript?",
      "store": true
    },
    {
      "type": "confirm",
      "name": "css",
      "message": "Does your project use css?",
      "store": true
    }
  }
}

The above yoga.json file would prompt you with two questions every time you run your generator and store them in js and css variables. These variables drive the main two aspects of scaffolding: file copying and templating.

1. File Copying

You can control which files in /app/templates get copied into your new project by prefixing filenames with expressions that include prompt variables.

.
├── index.html
├── {js}scripts
│   └── main.js
└── {css}styles
    └── main.css

In the above example, the scripts folder will only be copied if js (as declared in yoga.json) is true, and the styles folder will only be copied if css is true.

Some notes about file copying:

• Empty expressions are a great way to include system and hidden files in your templates folder without them having an effect until they are copied:

  • {}package.json
  • {}.gitignore

• If a folder name only consists of an expression, all files will be copied to the parent folder:

  main.js
  {js}
    ├── 1.js
    ├── 2.js
    └── 3.js

        ⇨

  main.js
  1.js
  2.js
  3.js

• Expressions can be any boolean Javascript statement:

  {js && gulp}gulpfile.js

See prefixnote for the nitty-gritty.

2. Templating

You can use striate, a superset of ejs, to control which code gets generated within the files. The answers given to the prompts in yoga.json are available as variables within the scope of your template files.

<!DOCTYPE html>
<html>
<head>
  >> if(css) {
  <link rel='Stylesheet' type='text/css' href='styles/main.css'>
  >> }
</head>
<body>
  >> if(js) {
  <script src='scripts/main.js'></script>
  >> }
</body>
</html>

You can see a complete yoga generator with prompts, file prefixes, and templating at generator-yoga-sample.

License

ISC © Raine Lourie