Class: Async::HTTP::Body::Writable

Inherits:
Readable
  • Object
show all
Defined in:
lib/async/http/body/writable.rb

Overview

A dynamic body which you can write to and read from.

Instance Method Summary collapse

Methods inherited from Readable

#close, #each, #join, #length

Constructor Details

#initialize ⇒ Writable

Returns a new instance of Writable.



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# File 'lib/async/http/body/writable.rb', line 30

def initialize
  @queue = Async::Queue.new
  
  @count = 0
  
  @finished = false
  @stopped = nil
end

Instance Method Details

#empty? ⇒ Boolean

Has the producer called #finish and has the reader consumed the nil token?

Returns:

  • (Boolean) 


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# File 'lib/async/http/body/writable.rb', line 40

def empty?
  @finished
end

#finish ⇒ Object

Signal that output has finished. This must be called at least once.



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# File 'lib/async/http/body/writable.rb', line 82

def finish
  @queue.enqueue(nil)
end

#inspect ⇒ Object 



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# File 'lib/async/http/body/writable.rb', line 86

def inspect
  "\#<#{self.class} #{@count} chunks written#{@finished ? ', finished' : ''}>"
end

#read ⇒ Object

Read the next available chunk.



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# File 'lib/async/http/body/writable.rb', line 45

def read
  # I'm not sure if this is a good idea.
  # if @stopped
  #  raise @stopped
  # end
  
  return if @finished
  
  unless chunk = @queue.dequeue
    @finished = true
  end
  
  return chunk
end

#stop(error) ⇒ Object

Stop generating output; cause the next call to write to fail with the given error.



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# File 'lib/async/http/body/writable.rb', line 61

def stop(error)
  @stopped ||= error
end

#write(chunk) ⇒ Object Also known as: <<

Write a single chunk to the body. Signal completion by calling ‘#finish`.



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# File 'lib/async/http/body/writable.rb', line 66

def write(chunk)
  # If the reader breaks, the writer will break.
  # The inverse of this is less obvious (*)
  if @stopped
    raise @stopped
  end
  
  # TODO should this yield if the queue is full?
  
  @count += 1
  @queue.enqueue(chunk)
end