Class: CoRE::CoAP::Message

Inherits:
Struct
  • Object
show all
Defined in:
lib/core/coap/message.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*args) ⇒ Message

convenience: .new(tt?, mcode?, mid?, payload?, hash?)


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# File 'lib/core/coap/message.rb', line 7

def initialize(*args) # convenience: .new(tt?, mcode?, mid?, payload?, hash?)
  if args.size < 6
    h = {}
    h = args.pop.dup if args.last.is_a? Hash

    tt = h.delete(:tt) || args.shift

    mcode = h.delete(:mcode) || args.shift

    # TODO Allow later setting of mcode by Float.
    case mcode
      when Integer
        mcode = METHODS[mcode] || [mcode >> 5, mcode & 0x1f]
      when Float
        mcode = [mcode.to_i, (mcode * 100 % 100).round] # Accept 2.05 and such
    end

    mid = h.delete(:mid) || args.shift

    payload = h.delete(:payload) || args.shift || EMPTY

    unless args.empty?
      raise 'CoRE::CoAP::Message.new: Either specify Hash or all arguments.'
    end

    super(1, tt, mcode, mid, h, payload)
  else
    super
  end
end

Instance Attribute Details

#mcodeObject

Returns the value of attribute mcode

Returns:

  • (Object)

    the current value of mcode


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# File 'lib/core/coap/message.rb', line 6

def mcode
  @mcode
end

#midObject

Returns the value of attribute mid

Returns:

  • (Object)

    the current value of mid


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# File 'lib/core/coap/message.rb', line 6

def mid
  @mid
end

#optionsObject

Returns the value of attribute options

Returns:

  • (Object)

    the current value of options


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# File 'lib/core/coap/message.rb', line 6

def options
  @options
end

#payloadObject

Returns the value of attribute payload

Returns:

  • (Object)

    the current value of payload


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# File 'lib/core/coap/message.rb', line 6

def payload
  @payload
end

#ttObject

Returns the value of attribute tt

Returns:

  • (Object)

    the current value of tt


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# File 'lib/core/coap/message.rb', line 6

def tt
  @tt
end

#verObject

Returns the value of attribute ver

Returns:

  • (Object)

    the current value of ver


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# File 'lib/core/coap/message.rb', line 6

def ver
  @ver
end

Class Method Details

.decode_options_and_put_together(b1, tt, mcode, mid, options, payload) ⇒ Object


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# File 'lib/core/coap/message.rb', line 124

def self.decode_options_and_put_together(b1, tt, mcode, mid, options, payload)
  # check and decode option values
  decoded_options = CoAP::DEFAULTING_OPTIONS.dup
  options.each_pair do |k, v|
    if oinfo = CoAP::OPTIONS[k]
      oname, _, minmax, repeatable, decoder, _ = *oinfo
      repeatable or v.size <= 1 or
        raise ArgumentError, "repeated unrepeatable option #{oname}"
      v.each do |v1|
        unless minmax === v1.bytesize
          raise ArgumentError, "#{v1.inspect} out of #{minmax} for #{oname}"
        end
      end
      decoded_options[oname] = decoder.call(v)
    else
      decoded_options[k] = v # we don't know what that is -- keep it in raw
    end
  end

  new(b1, tt, mcode, mid, Hash[decoded_options], payload) # XXX: why Hash[] again?
end

.deklausify(d, dpos, len) ⇒ Object


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# File 'lib/core/coap/message.rb', line 146

def self.deklausify(d, dpos, len)
  case len
  when 0..12
    [len, dpos]
  when 13
    [d.getbyte(dpos) + 13, dpos += 1]
  when 14
    [d.byteslice(dpos, 2).unpack("n")[0] + 269, dpos += 2]
  else
    raise "[#{d.inspect}] Bad delta/length nibble #{len} at #{dpos}"
  end
end

.parse(d) ⇒ Object

Raises:

  • (ArgumentError)

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# File 'lib/core/coap/message.rb', line 159

def self.parse(d)
  # dpos keeps our current position in parsing d
  b1, mcode, mid = d.unpack("CCn"); dpos = 4
  toklen = b1 & 0xf
  token = d.byteslice(dpos, toklen); dpos += toklen
  b1 >>= 4
  tt = TTYPES[b1 & 0x3]
  b1 >>= 2
  raise ArgumentError, "unknown CoAP version #{b1}" unless b1 == 1
  mcode = METHODS[mcode] || [mcode>>5, mcode&0x1F]

  # collect options
  onumber = 0             # current option number
  options = Hash.new { |h, k| h[k] = [] }
  dlen = d.bytesize
  while dpos < dlen
    tl1 = d.getbyte(dpos); dpos += 1
    raise ArgumentError, "option is not there at #{dpos} with oc #{orig_numopt}" unless tl1 # XXX

    break if tl1 == 0xff

    odelta, dpos = deklausify(d, dpos, tl1 >> 4)
    olen, dpos = deklausify(d, dpos, tl1 & 0xF)

    onumber += odelta

    if dpos + olen > dlen
      raise ArgumentError, "#{olen}-byte option at #{dpos} -- not enough data in #{dlen} total"
    end

    oval = d.byteslice(dpos, olen); dpos += olen
    options[onumber] << oval
  end

  options[CoAP::TOKEN_ON] = [token] if token != ''
  
  # d.bytesize = more than all the rest...
  decode_options_and_put_together(b1, tt, mcode, mid, options,
                                  d.byteslice(dpos, d.bytesize))
end

Instance Method Details

#klausify(n) ⇒ Object


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# File 'lib/core/coap/message.rb', line 38

def klausify(n)
  if n < 13
    [n, '']
  else
    n -= 13
    if n < 256
      [13, [n].pack("C")]
    else
      [14, [n-256].pack("n")]
    end
  end
end

#mcode_readableObject


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# File 'lib/core/coap/message.rb', line 51

def mcode_readable
  return "#{mcode[0]}.#{"%02d" % mcode[1]}" if mcode.is_a? Array
  mcode.to_s
end

#prepare_optionsObject


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# File 'lib/core/coap/message.rb', line 56

def prepare_options
  prepared_options = {}
  options.each do |k, v|
    if oinfo_i = CoAP::OPTIONS_I[k]
      onum, oname, defv, minmax, rep, _, encoder = *oinfo_i
      prepared_options[onum] = a = encoder.call(v)
      rep or a.size <= 1 or raise "repeated option #{oname} #{a.inspect}"
      a.each do |v1|
        unless minmax === v1.bytesize
          raise ArgumentError, "#{v1.inspect} out of #{minmax} for #{oname}"
        end
      end
    else
      raise ArgumentError, "#{k.inspect}: unknown option" unless Integer === k
      prepared_options[k] = Array(v) # store raw option
    end
  end
  prepared_options
end

#to_sObject


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# File 'lib/core/coap/message.rb', line 76

def to_s
  path  = CoAP.path_encode(self.options[:uri_path])
  query = CoAP.query_encode(self.options[:uri_query])

  [tt, mcode_readable, path, query].join(' ').rstrip
end

#to_wireObject


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# File 'lib/core/coap/message.rb', line 83

def to_wire
  # check and encode option values
  prepared_options = prepare_options

  token = (prepared_options.delete(CoAP::TOKEN_ON) || [nil])[0] || ''

  b1 = 0x40 | TTYPES_I[tt] << 4 | token.bytesize
  b2 = METHODS_I[mcode] || (mcode[0] << 5) + mcode[1]
  result = [b1, b2, mid].pack("CCn")
  result << token

  # stuff options in packet
  onumber = 0
  num_encoded_options = 0
  prepared_options.keys.sort.each do |k|
    raise "Bad Option Type #{k.inspect}" unless Integer === k && k >= 0
    a = prepared_options[k]
    a.each do |v|
      # result << frob(k, v)
      odelta = k - onumber
      onumber = k

      odelta1, odelta2 = klausify(odelta)
      odelta1 <<= 4

      length1, length2 = klausify(v.bytesize)
      result << [odelta1 | length1].pack("C")
      result << odelta2
      result << length2
      result << v.dup.force_encoding(CoAP::BIN)         # value
    end
  end

  if payload != '' && !payload.nil?
    result << 0xFF
    result << payload.dup.force_encoding(CoAP::BIN)
  end

  result
end