rails--rails/actionpack/lib/action_view/flows.rb

76 lines
1.7 KiB
Ruby

require 'active_support/core_ext/string/output_safety'
module ActionView
class OutputFlow #:nodoc:
attr_reader :content
def initialize
@content = Hash.new { |h,k| h[k] = ActiveSupport::SafeBuffer.new }
end
# Called by _layout_for to read stored values.
def get(key)
@content[key]
end
# Called by each renderer object to set the layout contents.
def set(key, value)
@content[key] = value
end
# Called by content_for
def append(key, value)
@content[key] << value
end
alias_method :append!, :append
end
class StreamingFlow < OutputFlow #:nodoc:
def initialize(view, fiber)
@view = view
@parent = nil
@child = view.output_buffer
@content = view.view_flow.content
@fiber = fiber
@root = Fiber.current.object_id
end
# Try to get an stored content. If the content
# is not available and we are inside the layout
# fiber, we set that we are waiting for the given
# key and yield.
def get(key)
return super if @content.key?(key)
if inside_fiber?
view = @view
begin
@waiting_for = key
view.output_buffer, @parent = @child, view.output_buffer
Fiber.yield
ensure
@waiting_for = nil
view.output_buffer, @child = @parent, view.output_buffer
end
end
super
end
# Appends the contents for the given key. This is called
# by provides and resumes back to the fiber if it is
# the key it is waiting for.
def append!(key, value)
super
@fiber.resume if @waiting_for == key
end
private
def inside_fiber?
Fiber.current.object_id != @root
end
end
end