Class: OpenC3::TemplateAccessor

Inherits:
Accessor show all
Defined in:
lib/openc3/accessors/template_accessor.rb

Instance Attribute Summary

Attributes inherited from Accessor

#packet

Instance Method Summary collapse

Methods inherited from Accessor

#args, convert_to_type, read_item, read_items, write_item, write_items

Constructor Details

#initialize(packet, left_char = '<', right_char = '>') ⇒ TemplateAccessor

Returns a new instance of TemplateAccessor.



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# File 'lib/openc3/accessors/template_accessor.rb', line 18

def initialize(packet, left_char = '<', right_char = '>')
  super(packet)
  @left_char = left_char
  @right_char = right_char
  @configured = false
  @args = [left_char, right_char]
end

Instance Method Details

#configure ⇒ Object 



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# File 'lib/openc3/accessors/template_accessor.rb', line 26

def configure
  return if @configured

  escaped_left_char = @left_char
  escaped_left_char = "\\#{@left_char}" if @left_char == '('
  escaped_right_char = @right_char
  escaped_right_char = "\\#{@right_char}" if @right_char == ')'

  # Convert the template into a Regexp for reading each item
  template = @packet.template.dup
  template_items = template.scan(Regexp.new("#{escaped_left_char}.*?#{escaped_right_char}"))
  escaped_read_template = Regexp.escape(template)

  @item_keys = []
  template_items.each do |item|
    @item_keys << item[1..-2]
    # If they're using parens we have to escape them
    # since we're working with the already escaped template
    item = "\\#{item}" if @left_char == '('
    item = "#{item[0..-2]}\\)" if @right_char == ')'
    escaped_read_template.gsub!(item, "(.*)")
  end
  @read_regexp = Regexp.new(escaped_read_template)
  @configured = true
end

#enforce_derived_write_conversion(_item) ⇒ Object

If this is true it will enforce that COSMOS DERIVED items must have a write_conversion to be written



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# File 'lib/openc3/accessors/template_accessor.rb', line 148

def enforce_derived_write_conversion(_item)
  return true
end

#enforce_encoding ⇒ Object

If this is set it will enforce that buffer data is encoded in a specific encoding



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# File 'lib/openc3/accessors/template_accessor.rb', line 128

def enforce_encoding
  return nil
end

#enforce_length ⇒ Object

This affects whether the Packet class enforces the buffer length at all. Set to false to remove any correlation between buffer length and defined sizes of items in COSMOS



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# File 'lib/openc3/accessors/template_accessor.rb', line 135

def enforce_length
  return false
end

#enforce_short_buffer_allowed ⇒ Object

This sets the short_buffer_allowed flag in the Packet class which allows packets that have a buffer shorter than the defined size. Items outside the buffer bounds will return nil when read.



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# File 'lib/openc3/accessors/template_accessor.rb', line 142

def enforce_short_buffer_allowed
  return true
end

#read_item(item, buffer) ⇒ Object 



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# File 'lib/openc3/accessors/template_accessor.rb', line 52

def read_item(item, buffer)
  return nil if item.data_type == :DERIVED
  configure()

  # No template items to read (e.g. command with fixed template string)
  return nil if @item_keys.empty?

  # Scan the response for all the variables in brackets <VARIABLE>
  values = buffer.scan(@read_regexp)[0]
  if !values || (values.length != @item_keys.length)
    raise "Unexpected number of items found in buffer: #{values ? values.length : 0}, Expected: #{@item_keys.length}"
  else
    values.each_with_index do |value, i|
      item_key = @item_keys[i]
      if item_key == item.key
        return self.class.convert_to_type(value, item)
      end
    end
  end

  raise "Response does not include key #{item.key}: #{buffer}"
end

#read_items(items, buffer) ⇒ Object 



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# File 'lib/openc3/accessors/template_accessor.rb', line 75

def read_items(items, buffer)
  result = {}
  configure()

  # No template items to read (e.g. command with fixed template string)
  if @item_keys.empty?
    items.each { |item| result[item.name] = nil }
    return result
  end

  # Scan the response for all the variables in brackets <VARIABLE>
  values = buffer.scan(@read_regexp)[0]
  if !values || (values.length != @item_keys.length)
    raise "Unexpected number of items found in buffer: #{values ? values.length : 0}, Expected: #{@item_keys.length}"
  else
    items.each do |item|
      if item.data_type == :DERIVED
        result[item.name] = nil
        next
      end
      index = @item_keys.index(item.key)
      if index
        result[item.name] = self.class.convert_to_type(values[index], item)
      else
        raise "Unknown item with key #{item.key} requested"
      end
    end
  end

  return result
end

#write_item(item, value, buffer) ⇒ Object 



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# File 'lib/openc3/accessors/template_accessor.rb', line 107

def write_item(item, value, buffer)
  return nil if item.data_type == :DERIVED
  configure()

  success = buffer.gsub!("#{@left_char}#{item.key}#{@right_char}", value.to_s)
  raise "Key #{item.key} not found in template" unless success
  return value
end

#write_items(items, values, buffer) ⇒ Object 



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# File 'lib/openc3/accessors/template_accessor.rb', line 116

def write_items(items, values, buffer)
  configure()
  items.each_with_index do |item, index|
    next if item.data_type == :DERIVED
    success = buffer.gsub!("#{@left_char}#{item.key}#{@right_char}", values[index].to_s)
    raise "Key #{item.key} not found in template" unless success
  end
  return values
end