Class: HTTP2::FrameBuffer

Inherits:
Object
  • Object
show all
Defined in:
lib/http/2/flow_buffer.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initializeFrameBuffer

Returns a new instance of FrameBuffer.



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# File 'lib/http/2/flow_buffer.rb', line 120

def initialize
  @buffer = []
  @bytesize = 0
end

Instance Attribute Details

#bytesizeObject (readonly)

Returns the value of attribute bytesize.



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# File 'lib/http/2/flow_buffer.rb', line 118

def bytesize
  @bytesize
end

Instance Method Details

#<<(frame) ⇒ Object



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# File 'lib/http/2/flow_buffer.rb', line 125

def <<(frame)
  @buffer << frame
  @bytesize += frame[:payload].bytesize
end

#empty?Boolean

Returns:

  • (Boolean)


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# File 'lib/http/2/flow_buffer.rb', line 130

def empty?
  @buffer.empty?
end

#retrieve(window_size) ⇒ Object



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# File 'lib/http/2/flow_buffer.rb', line 134

def retrieve(window_size)
  frame = @buffer.first or return

  frame_size = frame[:payload].bytesize
  end_stream = frame[:flags].include?(:end_stream)

  # Frames with zero length with the END_STREAM flag set (that
  # is, an empty DATA frame) MAY be sent if there is no available space
  # in either flow control window.
  return if window_size <= 0 && !(frame_size.zero? && end_stream)

  if frame_size > window_size
    chunk   = frame.dup
    payload = frame[:payload]

    # Split frame so that it fits in the window
    # TODO: consider padding!

    chunk[:payload] = payload.byteslice(0, window_size)
    chunk[:length]  = window_size
    frame[:payload] = payload.byteslice(window_size..-1)
    frame[:length] = frame_size - window_size

    # if no longer last frame in sequence...
    chunk[:flags] -= [:end_stream] if end_stream

    @bytesize -= window_size
    chunk
  else
    @bytesize -= frame_size
    @buffer.shift
  end
end