Module: Protocol::HTTP2::FlowControl
- Included in:
- Connection, Stream
- Defined in:
- lib/protocol/http2/flow_control.rb
Instance Method Summary collapse
-
#available_frame_size(maximum_frame_size = self.maximum_frame_size) ⇒ Object
This could be negative if the window has been overused due to a change in initial window size.
- #available_size ⇒ Object
- #consume_local_window(frame) ⇒ Object
-
#consume_remote_window(frame) ⇒ Object
Keep track of the amount of data sent, and fail if is too much.
-
#consume_window(size = self.available_size) ⇒ Object
Traverse active streams in order of priority and allow them to consume the available flow-control window.
- #receive_window_update(frame) ⇒ Object
-
#send_window_update(window_increment) ⇒ Object
Notify the remote end that we are prepared to receive more data:.
-
#window_updated(size = self.available_size) ⇒ Boolean
The window has been expanded by the given amount.
Instance Method Details
#available_frame_size(maximum_frame_size = self.maximum_frame_size) ⇒ Object
This could be negative if the window has been overused due to a change in initial window size.
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# File 'lib/protocol/http2/flow_control.rb', line 31 def available_frame_size(maximum_frame_size = self.maximum_frame_size) available_size = self.available_size # puts "available_size=#{available_size} maximum_frame_size=#{maximum_frame_size}" if available_size < maximum_frame_size return available_size else return maximum_frame_size end end |
#available_size ⇒ Object
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# File 'lib/protocol/http2/flow_control.rb', line 26 def available_size @remote_window.available end |
#consume_local_window(frame) ⇒ Object
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# File 'lib/protocol/http2/flow_control.rb', line 57 def consume_local_window(frame) amount = frame.length @local_window.consume(amount) if @local_window.limited? self.send_window_update(@local_window.used) end end |
#consume_remote_window(frame) ⇒ Object
Keep track of the amount of data sent, and fail if is too much.
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# File 'lib/protocol/http2/flow_control.rb', line 44 def consume_remote_window(frame) amount = frame.length # 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. if amount.zero? and frame.end_stream? # It's okay, we can send. No need to consume, it's empty anyway. elsif amount >= 0 and amount <= @remote_window.available @remote_window.consume(amount) else raise FlowControlError, "Trying to send #{frame.length} bytes, exceeded window size: #{@remote_window.available} (#{@remote_window})" end end |
#consume_window(size = self.available_size) ⇒ Object
Traverse active streams in order of priority and allow them to consume the available flow-control window.
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# File 'lib/protocol/http2/flow_control.rb', line 100 def consume_window(size = self.available_size) # Don't consume more than the available window size: size = [self.available_size, size].min # puts "consume_window(#{size}) local_window=#{@local_window} remote_window=#{@remote_window}" # Return if there is no window to consume: return unless size > 0 # Allow the current flow-controlled instance to use up the window: if !self.window_updated(size) and children = self.children children = children.values.sort_by(&:weight) # This must always be at least >= `children.count`, since stream weight can't be 0. total = children.sum(&:weight) children.each do |child| # Compute the proportional allocation: allocated = (child.weight * size) / total child.consume_window(allocated) end end end |
#receive_window_update(frame) ⇒ Object
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# File 'lib/protocol/http2/flow_control.rb', line 77 def receive_window_update(frame) amount = frame.unpack # puts "expanding remote_window=#{@remote_window} by #{amount}" if amount != 0 @remote_window.(amount) else raise ProtocolError, "Invalid window size increment: #{amount}!" end # puts "expanded remote_window=#{@remote_window} by #{amount}" end |
#send_window_update(window_increment) ⇒ Object
Notify the remote end that we are prepared to receive more data:
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# File 'lib/protocol/http2/flow_control.rb', line 68 def send_window_update(window_increment) frame = WindowUpdateFrame.new(self.id) frame.pack window_increment write_frame(frame) @local_window.(window_increment) end |
#window_updated(size = self.available_size) ⇒ Boolean
The window has been expanded by the given amount.
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# File 'lib/protocol/http2/flow_control.rb', line 94 def window_updated(size = self.available_size) return false end |