Class: ActionController::Dispatcher

Inherits:
Object
  • Object
show all
Defined in:
lib/action_controller/dispatcher.rb

Overview

Dispatches requests to the appropriate controller and takes care of reloading the app after each request when Dependencies.load? is true.

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(output, request = nil, response = nil) ⇒ Dispatcher

Returns a new instance of Dispatcher.



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# File 'lib/action_controller/dispatcher.rb', line 109

def initialize(output, request = nil, response = nil)
  @output, @request, @response = output, request, response
end

Class Method Details

.after_dispatch(*method_names, &block) ⇒ Object

Declare a block to be called after each dispatch. Run in reverse of the order declared.



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# File 'lib/action_controller/dispatcher.rb', line 21

def after_dispatch(*method_names, &block)
  callbacks[:after].concat method_names
  callbacks[:after] << block if block_given?
end

.before_dispatch(*method_names, &block) ⇒ Object

Declare a block to be called before each dispatch. Run in the order declared.



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# File 'lib/action_controller/dispatcher.rb', line 14

def before_dispatch(*method_names, &block)
  callbacks[:before].concat method_names
  callbacks[:before] << block if block_given?
end

.dispatch(cgi = nil, session_options = CgiRequest::DEFAULT_SESSION_OPTIONS, output = $stdout) ⇒ Object

Backward-compatible class method takes CGI-specific args. Deprecated in favor of Dispatcher.new(output, request, response).dispatch.



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# File 'lib/action_controller/dispatcher.rb', line 8

def dispatch(cgi = nil, session_options = CgiRequest::DEFAULT_SESSION_OPTIONS, output = $stdout)
  new(output).dispatch_cgi(cgi, session_options)
end

.failsafe_response(fallback_output, status, originating_exception = nil) ⇒ Object

If the block raises, send status code as a last-ditch response.



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# File 'lib/action_controller/dispatcher.rb', line 48

def failsafe_response(fallback_output, status, originating_exception = nil)
  yield
rescue Exception => exception
  begin
    log_failsafe_exception(status, originating_exception || exception)
    body = failsafe_response_body(status)
    fallback_output.write "Status: #{status}\r\nContent-Type: text/html\r\n\r\n#{body}"
    nil
  rescue Exception => failsafe_error # Logger or IO errors
    $stderr.puts "Error during failsafe response: #{failsafe_error}"
    $stderr.puts "(originally #{originating_exception})" if originating_exception
  end
end

.to_prepare(identifier = nil, &block) ⇒ Object

Add a preparation callback. Preparation callbacks are run before every request in development mode, and before the first request in production mode.

An optional identifier may be supplied for the callback. If provided, to_prepare may be called again with the same identifier to replace the existing callback. Passing an identifier is a suggested practice if the code adding a preparation block may be reloaded.



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# File 'lib/action_controller/dispatcher.rb', line 34

def to_prepare(identifier = nil, &block)
  # Already registered: update the existing callback
  if identifier
    if callback = callbacks[:prepare].assoc(identifier)
      callback[1] = block
    else
      callbacks[:prepare] << [identifier, block]
    end
  else
    callbacks[:prepare] << block
  end
end

Instance Method Details

#cleanup_application(force = false) ⇒ Object

Cleanup the application by clearing out loaded classes so they can be reloaded on the next request without restarting the server.



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# File 'lib/action_controller/dispatcher.rb', line 156

def cleanup_application(force = false)
  if Dependencies.load? || force
    ActiveRecord::Base.reset_subclasses if defined?(ActiveRecord)
    Dependencies.clear
    ActiveRecord::Base.clear_reloadable_connections! if defined?(ActiveRecord)
  end
end

#dispatch ⇒ Object 



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# File 'lib/action_controller/dispatcher.rb', line 113

def dispatch
  run_callbacks :before
  handle_request
rescue Exception => exception
  failsafe_rescue exception
ensure
  run_callbacks :after, :reverse_each
end

#dispatch_cgi(cgi, session_options) ⇒ Object 



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# File 'lib/action_controller/dispatcher.rb', line 122

def dispatch_cgi(cgi, session_options)
  if cgi ||= self.class.failsafe_response(@output, '400 Bad Request') { CGI.new }
    @request = CgiRequest.new(cgi, session_options)
    @response = CgiResponse.new(cgi)
    dispatch
  end
rescue Exception => exception
  failsafe_rescue exception
end

#flush_logger ⇒ Object 



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# File 'lib/action_controller/dispatcher.rb', line 164

def flush_logger
  RAILS_DEFAULT_LOGGER.flush if defined?(RAILS_DEFAULT_LOGGER) && RAILS_DEFAULT_LOGGER.respond_to?(:flush)
end

#prepare_application(force = false) ⇒ Object 



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# File 'lib/action_controller/dispatcher.rb', line 139

def prepare_application(force = false)
  begin
    require_dependency 'application' unless defined?(::ApplicationController)
  rescue LoadError => error
    raise unless error.message =~ /application\.rb/
  end

  ActiveRecord::Base.verify_active_connections! if defined?(ActiveRecord)

  if unprepared || force
    run_callbacks :prepare
    self.unprepared = false
  end
end

#reload_application ⇒ Object 



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# File 'lib/action_controller/dispatcher.rb', line 132

def reload_application
  if Dependencies.load?
    Routing::Routes.reload
    self.unprepared = true
  end
end