Module: Rackup::Handler

Defined in:
lib/rackup/handler.rb,
lib/rackup/handler/cgi.rb,
lib/rackup/handler/webrick.rb

Overview

Handlers connect web servers with Rack.

Rackup includes Handlers for WEBrick and CGI.

Handlers usually are activated by calling MyHandler.run(myapp). A second optional hash can be passed to include server-specific configuration.

Defined Under Namespace

Classes: CGI, WEBrick

Constant Summary collapse

RACK_HANDLER = 
'RACK_HANDLER'
RACKUP_HANDLER = 
'RACKUP_HANDLER'

Class Method Summary collapse

Class Method Details

.[](name) ⇒ Object 



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# File 'lib/rackup/handler.rb', line 14

def self.[](name)
  begin
    Rack::Handler[name] || self.const_get(name, false)
  rescue NameError
    # Ignore.
  end
end

.default ⇒ Object 



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# File 'lib/rackup/handler.rb', line 68

def self.default
  if rack_handler = ENV[RACKUP_HANDLER]
    self.get(rack_handler)
  elsif rack_handler = ENV[RACK_HANDLER]
    warn "RACK_HANDLER is deprecated, use RACKUP_HANDLER."
    self.get(rack_handler)
  else
    pick SERVER_NAMES
  end
end

.get(name) ⇒ Object 



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# File 'lib/rackup/handler.rb', line 22

def self.get(name)
  return nil unless name

  name = name.to_sym

  if server = self[name]
    return server
  end

  require_handler("rack/handler", name)

  return self[name]
end

.pick(server_names) ⇒ Object

Select first available Rack handler given an ‘Array` of server names. Raises `LoadError` if no handler was found.

> pick ['puma', 'webrick']
=> Rackup::Handler::WEBrick

Raises:

  • (LoadError) 


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# File 'lib/rackup/handler.rb', line 53

def self.pick(server_names)
  server_names = Array(server_names)

  server_names.each do |server_name|
    begin
      server = self.get(server_name)
     return server if server
    rescue LoadError
      # Ignore.
    end
  end

  raise LoadError, "Couldn't find handler for: #{server_names.join(', ')}."
end

.register(name, klass) ⇒ Object 



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# File 'lib/rackup/handler.rb', line 36

def self.register(name, klass)
  name = name.to_sym

  Rack::Handler.register(name, klass)
end

.require_handler(prefix, const_name) ⇒ Object

Transforms server-name constants to their canonical form as filenames, then tries to require them but silences the LoadError if not found

Naming convention:

Foo # => 'foo'
FooBar # => 'foo_bar.rb'
FooBAR # => 'foobar.rb'
FOObar # => 'foobar.rb'
FOOBAR # => 'foobar.rb'
FooBarBaz # => 'foo_bar_baz.rb'



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# File 'lib/rackup/handler.rb', line 90

def self.require_handler(prefix, const_name)
  file = const_name.to_s.gsub(/^[A-Z]+/) { |pre| pre.downcase }.
    gsub(/[A-Z]+[^A-Z]/, '_\&').downcase

  require(::File.join(prefix, file))
end