class Async::HTTP::Body::Pipe

def writer(task)

A write-side close on @tail produces EOF and closes @output independently of the input direction.
Read from the head of the pipe and write to the @output stream. 
def writer(task)
	@writer = task
	
	task.annotate "#{self.class} writer."
	
	while chunk = @head.read_partial
		@output.write(chunk)
	end
rescue => error
ensure
	@output.close_write(error)
	
	close_head if @reader&.finished?
end