elia/simple_server.rb

## simple_server.rb
require 'opal/deprecations'

# Opal::SimpleServer is a very basic Rack server for Opal assets, it relies on
# Opal::Builder and Ruby corelib/stdlib. It's meant to be used just for local
# development.
#
# For a more complete implementation see opal-sprockets (Rubygems) or
# opal-webpack (NPM).
#
# @example (CLI)
#   rackup -ropal -ropal/simple_server -b 'Opal.append_path("app"); run Opal::SimpleServer.new'
class Opal::SimpleServer
  require 'set'
  require 'erb'

  # @param cache [#[](key), #[]=(key, value)]
  #   The cache will be used to store
  def initialize(options = {})
    @cache = {}
    @debug = options.fetch(:debug, true)
    @prefix = options.fetch(:prefix, 'assets')
    @main = options.fetch(:main, 'application')
    yield self if block_given?
    freeze
  end

  attr_accessor :main, :index_path

  # @deprecated
  # It's here for compatibility with Opal::Sprockets::Server
  def append_path(path)
    Opal.deprecation 'Please use `Opal.append_path(path)` instead.'
    Opal.append_path path
  end

  def call(env)
    case env['PATH_INFO']
    when %r{\A/#{@prefix}/(.*)\.map\z}
      path, cache_invalidator = $1.split('?', 2)
      call_map(path)
    when %r{\A/#{@prefix}/(.*)\z}
      path, cache_invalidator = $1.split('?', 2)
      call_asset(path)
    else call_index
    end
  end

  def call_asset(path)
    asset = fetch_asset(path)
    [
      200,
      { 'Content-Type' => 'application/javascript',
        'X-SourceMap' => "/#{@prefix}/#{path}.map#{cache_invalidator}}" },
      [asset[:data]]
    ]
  end

  def call_map(path)
    asset = fetch_asset(path)
    [
      200,
      { 'Content-Type' => 'application/json' },
      [asset[:map]]
    ]
  end

  def fetch_asset(path)
    builder = Opal::Builder.new
    builder.build(path.gsub(/(\.(?:rb|js|opal))*\z/, ''))
    {
      data: builder.to_s,
      map: builder.source_map.to_json
    }
  end

  def javascript_include_tag(path)
    %{<script src="/#{@prefix}/#{path}.js#{cache_invalidator}"></script>}
  end

  def cache_invalidator
    "?#{Time.now.to_i}" if @debug
  end

  def call_index
    if @index_path
      contents = File.read(@index_path)
      html = ERB.new(contents).result binding
    else
      html = <<-HTML
      <!doctype html>
      <html>
        <head>
          <meta charset="utf8">
          #{javascript_include_tag(main)}
        </head>
        <body></body>
      </html>
      HTML
    end
    [200, {'Content-Type' => 'text/html'}, [html]]
  end

  def fetch_cache(key)
    unless (data = @cache[key])
      data = yield
      @cache[key] = data
    end
    data
  end
end
	require 'opal/deprecations'

	# Opal::SimpleServer is a very basic Rack server for Opal assets, it relies on
	# Opal::Builder and Ruby corelib/stdlib. It's meant to be used just for local
	# development.
	#
	# For a more complete implementation see opal-sprockets (Rubygems) or
	# opal-webpack (NPM).
	#
	# @example (CLI)
	# rackup -ropal -ropal/simple_server -b 'Opal.append_path("app"); run Opal::SimpleServer.new'
	class Opal::SimpleServer
	require 'set'
	require 'erb'

	# @param cache [#[](key), #[]=(key, value)]
	# The cache will be used to store
	def initialize(options = {})
	@cache = {}
	@debug = options.fetch(:debug, true)
	@prefix = options.fetch(:prefix, 'assets')
	@main = options.fetch(:main, 'application')
	yield self if block_given?
	freeze
	end

	attr_accessor :main, :index_path

	# @deprecated
	# It's here for compatibility with Opal::Sprockets::Server
	def append_path(path)
	Opal.deprecation 'Please use `Opal.append_path(path)` instead.'
	Opal.append_path path
	end

	def call(env)
	case env['PATH_INFO']
	when %r{\A/#{@prefix}/(.*)\.map\z}
	path, cache_invalidator = $1.split('?', 2)
	call_map(path)
	when %r{\A/#{@prefix}/(.*)\z}
	path, cache_invalidator = $1.split('?', 2)
	call_asset(path)
	else call_index
	end
	end

	def call_asset(path)
	asset = fetch_asset(path)
	[
	200,
	{ 'Content-Type' => 'application/javascript',
	'X-SourceMap' => "/#{@prefix}/#{path}.map#{cache_invalidator}}" },
	[asset[:data]]
	]
	end

	def call_map(path)
	asset = fetch_asset(path)
	[
	200,
	{ 'Content-Type' => 'application/json' },
	[asset[:map]]
	]
	end

	def fetch_asset(path)
	builder = Opal::Builder.new
	builder.build(path.gsub(/(\.(?:rb\|js\|opal))*\z/, ''))
	{
	data: builder.to_s,
	map: builder.source_map.to_json
	}
	end

	def javascript_include_tag(path)
	%{<script src="/#{@prefix}/#{path}.js#{cache_invalidator}"></script>}
	end

	def cache_invalidator
	"?#{Time.now.to_i}" if @debug
	end

	def call_index
	if @index_path
	contents = File.read(@index_path)
	html = ERB.new(contents).result binding
	else
	html = <<-HTML
	<!doctype html>
	<html>
	<head>
	<meta charset="utf8">
	#{javascript_include_tag(main)}
	</head>
	<body></body>
	</html>
	HTML
	end
	[200, {'Content-Type' => 'text/html'}, [html]]
	end

	def fetch_cache(key)
	unless (data = @cache[key])
	data = yield
	@cache[key] = data
	end
	data
	end
	end