Hologram

Hologram is a Ruby gem that parses comments in your CSS and helps you turn them into a beautiful style guide.

There are two steps to building a great style guide:

  1. Documenting your css and generating html examples.
  2. Styling the output of step 1.

The hologram gem itself is only concerned with step 1. This means you are free to make your style guide look however you would like. If you don't feel like going through this process yourself you can take a look at the templates in our example repository and use the assets defined there instead.

Installation

Add this line to your application's Gemfile:

gem 'hologram'

And then execute:

$ bundle

If you don't use bundler you can run gem install hologram.

Quick Start

hologram init

This will create a hologram_config.yml file (more on this below), and also create a starter _header.html and _footer.html file for you. You can then tweak the config values and start documenting your css.

Building the documentation is simply:

hologram

Details

There are two things you need to do to start using hologram:

  1. Create a YAML config file for your project.

  2. Go document some code!

Creating a YAML config file

Hologram needs a few configuration settings before it can begin to build your documentation for you. Once this is set up you can execute hologram by simply running:

hologram path/to/your/config.yml or (using bundler) bundle exec hologram path/to/your/config.yml

Your config file needs to contain the following key/value pairs

  • source: relative path to your source files

  • destination: relative path to where you want the documentation to be built to

  • documentation_assets: The path that contains supporting assets for the documentaiton page. This typically includes html fragments (header/footer, etc), styleguide specific CSS, javascript and any images. Hologram specifically looks for two files: _header.html and _footer.html, these are used to start and end every html page hologram generates.

Hologram treats _header.html and _footer.html as ERB files for each page that is generated you can access the title, file_name, and blocks. blocks is a list of each documenation block on the page. Each item in the list has a title, name, category, and optionally a parent. This is useful for, say, building a menu that lists each component. Nota Bene: Filenames that begin with underscores will not be copied into the destination folder.

  • custom_markdown: (optional) this is the filename of a class that extends RedCarpet::Render::HTML class. Use this for when you need additional classes or html tags for different parts of the page.

  • index: (optional) this is a category (see Documenting your styles section below) that will be used as the index.html.

  • dependencies: a list of relative paths to folders containing any dependencies your style guide has. These folders will be copied over into the documentation output directory. PUT THE CSS/JS THAT IS ACTUALLY BEING DOCUMENTED HERE

Example config file
# The directory containing the source files to parse
source: ../components

# The directory that hologram will build to
destination: ../docs

# The assets needed to build/style the docs (includes header.html, footer.html, etc)
documentation_assets: ../hologram_assets

# A custom markdown renderer that extends `RedCarpet::Render::HTML class`
custom_markdown: trulia_markdown_renderer.rb

# Any other asset folders that need to be copied to the destination folder
# This is where the CSS/JS you are actually documenting should go
dependencies:
    - ../build

Documenting your styles

Hologram will scan your .css|.scss|.sass|.less|.styl files within your source directory. It will look for comments that match the following:

/*doc
---
title: Buttons
name: button
category: Base CSS
---

Button styles can be applied to any element. Typically you'll want
to use either a `<button>` or an `<a>` element:

```html_example
  <button class="btn btnDefault">Click</button>
  <a class="btn btnDefault" href="trulia.com">Trulia!</a>
```

If your button is actually a link to another page, please use the
`<a>` element, while if your button performs an action, such as
submitting a form or triggering some javascript event, then use a
`<button>` element.

*/

The first section of the comment is a yaml block that defines certain aspects of the this documentation block (more on that in the next section). The second part is simply markdown as defined by Redcarpet.

Notice the use of html_example. This tells the markdown renderer that it should treat the example as...well...html. If your project uses haml you can also use haml_example. In that case the output will be html for the example and the code block will show the haml used to generate the html. For components that require javascript you can use js_example for your js. In addtion to outputing the js in a <code> block it will also wrap it in a <script> tag for execution.

Document YAML section

The yaml in the doc block can have any key value pair you deem important but it specifically looks for the following keys:

  • title: The title to display in the documents
  • category: This is the broad category for the component, all components in the same category will be written to the same page.
  • name: This is used for grouping components, by assigning a name a component can be referenced in another component as a parent.
  • parent: (Optional.) This should be the name of another components. If this is set the current component will be displayed as a section within the parent's documentation.

For example, you might have a component with the name buttons and another component named buttonSkins. You could set the parent for the buttonSkins component to be buttons. It would then nest the buttonSkins documentation inside the buttons documentation.

Each level of nesting (components are infinitely nestable) will have a heading tag that represents its depth. In the above example buttons would have an <h1> and buttonSkins would have an <h2>. This you can see this exact example in our demo repo, and the output of this nesting in our demo styleguide.

Documentation Assets

The documentation assets folder contains the html, css, js and images you'll need for making your style guide look beautiful.

Hologram doesn't care too much about to what is in here as it is intended to be custom for your style guide.

Styling Your Code Examples

Hologram uses pygments.rb gem to provide syntax highlighting for code examples. One of the assets that you probably want to include in your documentation assets folder is a css file that styles the "pygmentized" code examples. We use github.css which can be found along with the css we use to style code blocks here.

Supported Preprocessors/File Types

The following preprocessors/file types are supported by Hologram:

  • Sass (.scss, .sass)
  • Less (.less)
  • Stylus (.styl)
  • Vanilla CSS (.css)
  • Javascript (.js)
  • Markdown (.md, .markdown)

Extensions and Plugins

  • Guard Hologram is a sweet little gem that uses guard to monitor changes to your hologram project and rebuilds your styleguide on the fly as you make changes.

Contributing

  1. Fork it
  2. Create your feature/bug fix branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

License

Hologram is licensed under the MIT License