markout

crystal html dsl
Markout is an awesome Crystal DSL for HTML

Markout

Markout is an awesome Crystal DSL for HTML. It enables calling regular HTML tags as methods to generate HTML.

Markout ensures type-safe HTML with valid syntax, and automatically escapes attribute values. It supports HTML 4 and 5, and XHTML.

Examples:

p "A paragraph"
# => <p>A paragraph</p>

p do
  text "A paragraph"
end
# => <p>A paragraph</p>

h1 "A first-level heading", class: "heading"
# => <h1 class='heading'>A first-level heading</h1>

h1 class: "heading" do
  text "A first-level heading"
end
# => <h1 class='heading'>A first-level heading</h1>

ul id: "a-wrapper", class: "list-wrap" do
  ["aa", "bb", "cc"].each do |x|
    li x, class: "list-item"
  end
end
# => <ul id='a-wrapper' class='list-wrap'>
#      <li class='list-item'>aa</li>
#      <li class='list-item'>bb</li>
#      <li class='list-item'>cc</li>
#    </ul>

input type: "checkbox", checked: nil
# => HTML 4, 5: <input type='checkbox' checked>
# => XHTML: <input type='checkbox' checked='checked' />

Installation

Add this to your application's shard.yml:

dependencies:
  markout:
    github: GrottoPress/markout

Usage

Pages

With Markout, pages are created using regular Crystal structs and classes. Markout comes with a page mixin, which child pages can include, and override specific methods for their own use case:

require "markout"

# Create your own base page
abstract struct BasePage
  # Include the page mixin
  include Markout::Page

  # Set HTML version
  #
  # Versions:
  #   `HtmlVersion::HTML_5` (default)
  #   `HtmlVersion::XHTML_1_1`
  #   `HtmlVersion::XHTML_1_0`
  #   `HtmlVersion::HTML_4_01`
  #private def html_version : HtmlVersion
  #  HtmlVersion::XHTML_1_1
  #end

  private def body_tag_attr : NamedTuple
    {class: "my-body-class"}
  end

  private def inside_head : Nil
    meta charset: "UTF-8"
    head_content
  end

  private def inside_body : Nil
    header id: "header" do
      h1 "My First Heading Level", class: "heading"
      p "An awesome description", class: "description"
    end

    main id: main do
      body_content
    end

    footer id: "footer" do
      raw "<!-- I'm unescaped -->"
    end
  end

  private def head_content : Nil
  end

  private def body_content : Nil
  end
end

# Now, create a page
struct MyFirstPage < BasePage
  private def head_content : Nil
    title "My First Page"
  end

  private def body_content : Nil
    p "Hello from Markout!"
  end
end

# SEND OUTPUT TO CONSOLE

puts MyFirstPage.new
# => <!DOCTYPE html>\
#    <html lang='en'>\
#      <head profile='http://ab.c'>\
#        <meta charset='UTF-8'>\
#        <title>My First Page</title>\
#      </head>\
#      <body class='my-body-class'>\
#        <header id='header'>\
#          <h1 class='heading'>My First Heading Level</h1>\
#          <p class='description'>An awesome description</p>\
#        </header>\
#        <main id='main'>\
#          <p>Hello from Markout!</p>\
#        </main>\
#        <footer id='footer'>\
#          <!-- I'm unescaped -->\
#        </footer>\
#      </body>\
#    </html>

# OR, SERVE IT TO THE BROWSER

require "http/server"

server = HTTP::Server.new do |context|
  context.response.content_type = "text/html"
  context.response.print MyFirstPage.new
end

puts "Listening on http://#{server.bind_tcp(8080)}"

server.listen
# Visit 'http://localhost:8080' to see Markout in action

Components

You may extract out shared elements that do not exactly fit into the page inheritance structure as components, and mount them in your pages:

require "markout"

# Create your own base component
abstract struct BaseComponent
  include Markout::Component

  # Set HTML version
  #
  # Same as for pages.
  #private def html_version : HtmlVersion
  #  HtmlVersion::XHTML_1_1
  #end
end

# Create the component
struct MyFirstComponent < BaseComponent
  def initialize(@users : Array(String))
  end

  private def render : Nil
    ul class: "users" do
      @users.each do |user|
        li user, class: "user"
        # Same as `li class: "user" do text(user) end`
      end
    end
  end
end

# Mount the component
struct MySecondPage < BasePage
  def initialize(@users : Array(String))
  end

  private def head_content : Nil
    title "Component Test"
  end

  private def body_content : Nil
    div class: "users-wrap" do
      mount MyFirstComponent, @users # Or `mount MyFirstComponent.new(@users)`
    end
  end
end

#puts MySecondPage.new(["Kofi", "Ama", "Nana"])

A component may accept a block:

# Create the component
struct MyLinkComponent < BaseComponent
  def initialize(@url : String, &@block : Proc(Component, Nil))
  end

  private def render : Nil
    a href: @url, class: "link", "data-foo": "bar" do
      @block.call(self)
    end
  end
end

# Mount the component
struct MyThirdPage < BasePage
  private def body_content : Nil
    div class: "link-wrap" do
      mount MyLinkComponent, "http://ab.c" do |html|
        html.text("Abc")
      end
    end
  end
end

puts MyThirdPage.new
# => ...
#    <div class='link-wrap'>\
#      <a href='http://ab.c' class='link' data-foo='bar'>Abc</a>\
#    </div>
#    ...

To accept arbitrary arguments, you would have to do something different:

# Create the component
struct MyLinkComponent < BaseComponent
  def initialize(@label : String, @url : String, **opts)
    render_args(**opts)
  end

  private def render_args(**opts)
    args = opts.merge({href: @url})
    args = {class: "link"}.merge(args)

    a @label, **args
  end
end

# Mount the component
struct MyThirdPage < BasePage
  private def body_content : Nil
    div class: "link-wrap" do
      mount MyLinkComponent, "Abc", "http://ab.c", "data-foo": "bar"
    end
  end
end

puts MyThirdPage.new
# => ...
#    <div class='link-wrap'>\
#      <a data-foo='bar' href='http://ab.c'>Abc</a>\
#    </div>
#    ...

Custom Tags

You may define arbitrary tags with #tag. This is particularly useful for rendering JSX or similar:

tag :MyApp, title: "My Awesome App" do
  p "My app is the best."
end
# => <MyApp title='My Awesome App'>\
#      <p>My app is the best.</p>\
#    </MyApp>

tag :MyApp, title: "My Awesome App"
# => <MyApp title='My Awesome App' />

tag :cuboid, width: 4, height: 3, length: 2 do
  text "A cuboid"
end
# => <cuboid width='4' height='3' length='2'>
#      A cuboid
#    </cuboid>

Handy methods

Apart from calling regular HTML tags as methods, the following methods are available:

  • #raw(text : String): Use this render unescaped text
  • #text(text : String): Use this to render escaped text

Contributing

  1. Fork it
  2. Switch to the master branch: git checkout master
  3. Create your feature branch: git checkout -b my-new-feature
  4. Make your changes, updating changelog and documentation as appropriate.
  5. Commit your changes: git commit
  6. Push to the branch: git push origin my-new-feature
  7. Submit a new Pull Request against the GrottoPress:master branch.
Repository

markout

Owner
Statistic
  • 22
  • 1
  • 0
  • 1
  • 1
  • 3 months ago
  • October 2, 2018
License

MIT License

Links
Synced at

Thu, 21 Nov 2024 19:06:09 GMT

Languages
Crystal 100.0%