Class: GraphAgent::Channels::LastValue

Inherits:
BaseChannel show all
Defined in:
lib/graph_agent/channels/last_value.rb

Constant Summary

Constants inherited from BaseChannel

BaseChannel::MISSING

Instance Attribute Summary

Attributes inherited from BaseChannel

#key

Instance Method Summary collapse

Methods inherited from BaseChannel

#consume, #finish

Constructor Details

#initialize(key: "", default: MISSING) ⇒ LastValue

Returns a new instance of LastValue.



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# File 'lib/graph_agent/channels/last_value.rb', line 6

def initialize(key: "", default: MISSING)
  super(key: key)
  @value = default
end

Instance Method Details

#available? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/graph_agent/channels/last_value.rb', line 28

def available?
  !@value.equal?(MISSING)
end

#checkpoint ⇒ Object 



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# File 'lib/graph_agent/channels/last_value.rb', line 32

def checkpoint
  @value
end

#copy ⇒ Object 



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# File 'lib/graph_agent/channels/last_value.rb', line 42

def copy
  ch = self.class.new(key: key)
  ch.instance_variable_set(:@value, @value)
  ch
end

#from_checkpoint(checkpoint) ⇒ Object 



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# File 'lib/graph_agent/channels/last_value.rb', line 36

def from_checkpoint(checkpoint)
  ch = self.class.new(key: key)
  ch.instance_variable_set(:@value, checkpoint.equal?(MISSING) ? MISSING : checkpoint)
  ch
end

#get ⇒ Object

Raises:



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# File 'lib/graph_agent/channels/last_value.rb', line 11

def get
  raise EmptyChannelError.new("Channel '#{key}' is empty") if @value.equal?(MISSING)

  @value
end

#update(values) ⇒ Object 



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# File 'lib/graph_agent/channels/last_value.rb', line 17

def update(values)
  return false if values.empty?

  if values.length != 1
    raise InvalidUpdateError.new("At key '#{key}': Can receive only one value per step.")
  end

  @value = values.last
  true
end