Class: Cosmos::Packet

Inherits:
Structure show all
Defined in:
lib/cosmos/packets/packet.rb,
lib/cosmos/utilities/simulated_target.rb

Overview

Adds features common to all COSMOS packets of data to the Structure class. This includes the additional attributes listed below. The primary behavior Packet adds is the ability to apply formatting to PacketItem values as well as managing PacketItem’s limit states.

Direct Known Subclasses

CcsdsPacket, Table

Constant Summary collapse

RESERVED_ITEM_NAMES = 
['PACKET_TIMESECONDS'.freeze, 'PACKET_TIMEFORMATTED'.freeze, 'RECEIVED_TIMESECONDS'.freeze, 'RECEIVED_TIMEFORMATTED'.freeze, 'RECEIVED_COUNT'.freeze]
CATCH_ALL_STATE = 
'ANY'
VALUE_TYPES =

Valid format types

[:RAW, :CONVERTED, :FORMATTED, :WITH_UNITS]

Constants inherited from Structure

Structure::ASCII_8BIT_STRING, Structure::ZERO_STRING

Instance Attribute Summary collapse

Attributes inherited from Structure

#default_endianness, #defined_length, #defined_length_bits, #fixed_size, #items, #short_buffer_allowed, #sorted_items

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Structure

#append, #buffer, #defined?, #delete_item, #enable_method_missing, #length, #rename_item, #resize_buffer, #set_item

Constructor Details

#initialize(target_name, packet_name, default_endianness = :BIG_ENDIAN, description = nil, buffer = '', item_class = PacketItem) ⇒ Packet

Creates a new packet by initalizing the attributes.

Parameters:

  • target_name (String) —

    Name of the target this packet is associated with

  • packet_name (String) —

    Name of the packet

  • default_endianness (Symbol) (defaults to: :BIG_ENDIAN) —

    One of BinaryAccessor::ENDIANNESS

  • description (String) (defaults to: nil) —

    Description of the packet

  • buffer (String) (defaults to: '') —

    String buffer to hold the packet data

  • item_class (Class) (defaults to: PacketItem) —

    Class used to instantiate items (Must be a subclass of PacketItem)



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# File 'lib/cosmos/packets/packet.rb', line 89

def initialize(target_name, packet_name, default_endianness = :BIG_ENDIAN, description = nil, buffer = '', item_class = PacketItem)
  super(default_endianness, buffer, item_class)
  self.target_name = target_name
  self.packet_name = packet_name
  self.description = description
  @received_time = nil
  @received_count = 0
  @id_items = nil
  @hazardous = false
  @hazardous_description = nil
  @given_values = nil
  @limits_items = nil
  @processors = nil
  @stale = true
  @limits_change_callback = nil
  @read_conversion_cache = nil
  @raw = nil
  @messages_disabled = false
  @meta = nil
  @hidden = false
  @disabled = false
  @stored = false
  @extra = nil
end

Instance Attribute Details

#abstract ⇒ Boolean

Returns Whether or not this is a ‘abstract’ packet.

Returns:

  • (Boolean) —

    Whether or not this is a 'abstract' packet



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# File 'lib/cosmos/packets/packet.rb', line 68

def abstract
  @abstract
end

#description ⇒ String

Returns Description of the packet.

Returns:

  • (String) —

    Description of the packet



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# File 'lib/cosmos/packets/packet.rb', line 32

def description
  @description
end

#disabled ⇒ Boolean

Returns Whether or not this is a ‘disabled’ packet.

Returns:

  • (Boolean) —

    Whether or not this is a 'disabled' packet



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# File 'lib/cosmos/packets/packet.rb', line 62

def disabled
  @disabled
end

#extra ⇒ Hash

Returns Extra data to be logged/transferred with packet.

Returns:

  • (Hash) —

    Extra data to be logged/transferred with packet



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# File 'lib/cosmos/packets/packet.rb', line 74

def extra
  @extra
end

#given_values ⇒ Hash<Item Name, Value>

Contains the values given by the user for a command (distinguished from defaults) These values should be used within command conversions if present because the order that values are written into the actual packet can vary

Returns:

  • (Hash<Item Name, Value>) —

    Given values when constructing the packet



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# File 'lib/cosmos/packets/packet.rb', line 50

def given_values
  @given_values
end

#hazardous ⇒ Boolean

Returns Flag indicating if the packet is hazardous (typically for commands).

Returns:

  • (Boolean) —

    Flag indicating if the packet is hazardous (typically for commands)



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# File 'lib/cosmos/packets/packet.rb', line 41

def hazardous
  @hazardous
end

#hazardous_description ⇒ String

Returns Description of why the packet is hazardous.

Returns:

  • (String) —

    Description of why the packet is hazardous



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# File 'lib/cosmos/packets/packet.rb', line 44

def hazardous_description
  @hazardous_description
end

#hidden ⇒ Boolean

Returns Whether or not this is a ‘hidden’ packet.

Returns:

  • (Boolean) —

    Whether or not this is a 'hidden' packet



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# File 'lib/cosmos/packets/packet.rb', line 59

def hidden
  @hidden
end

#messages_disabled ⇒ Boolean

Returns Whether or not messages should be printed for this packet.

Returns:

  • (Boolean) —

    Whether or not messages should be printed for this packet



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# File 'lib/cosmos/packets/packet.rb', line 65

def messages_disabled
  @messages_disabled
end

#packet_name ⇒ String

Returns Name of the packet.

Returns:

  • (String) —

    Name of the packet



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# File 'lib/cosmos/packets/packet.rb', line 29

def packet_name
  @packet_name
end

#packet_rate ⇒ Object

Returns the value of attribute packet_rate.



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# File 'lib/cosmos/utilities/simulated_target.rb', line 17

def packet_rate
  @packet_rate
end

#raw ⇒ Boolean

Returns Whether or not this is a ‘raw’ packet.

Returns:

  • (Boolean) —

    Whether or not this is a 'raw' packet



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# File 'lib/cosmos/packets/packet.rb', line 56

def raw
  @raw
end

#received_count ⇒ Integer

Returns Number of times the packet has been received.

Returns:

  • (Integer) —

    Number of times the packet has been received



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# File 'lib/cosmos/packets/packet.rb', line 38

def received_count
  @received_count
end

#received_time ⇒ Time

Returns Time at which the packet was received.

Returns:

  • (Time) —

    Time at which the packet was received



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# File 'lib/cosmos/packets/packet.rb', line 35

def received_time
  @received_time
end

#stale ⇒ Boolean (readonly)

Returns Flag indicating if the packet is stale (hasn’t been received recently).

Returns:

  • (Boolean) —

    Flag indicating if the packet is stale (hasn't been received recently)



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# File 'lib/cosmos/packets/packet.rb', line 53

def stale
  @stale
end

#stored ⇒ Boolean

Returns Whether or not this was a stored packet.

Returns:

  • (Boolean) —

    Whether or not this was a stored packet



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# File 'lib/cosmos/packets/packet.rb', line 71

def stored
  @stored
end

#target_name ⇒ String

Returns Name of the target this packet is associated with.

Returns:

  • (String) —

    Name of the target this packet is associated with



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# File 'lib/cosmos/packets/packet.rb', line 26

def target_name
  @target_name
end

Class Method Details

.next_bit_offset(item) ⇒ Integer

Returns the bit offset of the next item after the current item if items are packed

Parameters:

  • item (PacketItem) —

    The item to calculate the next offset for

Returns:

  • (Integer) —

    Bit Offset of Next Item if Packed



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# File 'lib/cosmos/packets/packet.rb', line 373

def self.next_bit_offset(item)
  if item.array_size
    if item.array_size > 0
      next_offset = item.bit_offset + item.array_size
    else
      next_offset = item.array_size
    end
  else
    next_offset = nil
    if item.bit_offset > 0
      if item.little_endian_bit_field?
        # Bit offset always refers to the most significant bit of a bitfield
        bits_remaining_in_last_byte = 8 - (item.bit_offset % 8)
        if item.bit_size > bits_remaining_in_last_byte
          next_offset = item.bit_offset + bits_remaining_in_last_byte
        end
      end
    end
    unless next_offset
      if item.bit_size > 0
        next_offset = item.bit_offset + item.bit_size
      else
        next_offset = item.bit_size
      end
    end
  end
  next_offset
end

Instance Method Details

#append_item(name, bit_size, data_type, array_size = nil, endianness = @default_endianness, overflow = :ERROR, format_string = nil, read_conversion = nil, write_conversion = nil, id_value = nil) ⇒ PacketItem

Define an item at the end of the packet. This creates a new instance of the item_class as given in the constructor and adds it to the items hash. It also resizes the buffer to accomodate the new item.

Parameters:

  • name (String) —

    Name of the item. Used by the items hash to retrieve the item.

  • bit_size (Integer) —

    Bit size of the item in the raw buffer

  • data_type (Symbol) —

    Type of data contained by the item. This is dependant on the item_class but by default see StructureItem.

  • array_size (Integer) (defaults to: nil) —

    Set to a non nil value if the item is to represented as an array.

  • endianness (Symbol) (defaults to: @default_endianness) —

    Endianness of this item. By default the endianness as set in the constructure is used.

  • overflow (Symbol) (defaults to: :ERROR) —

    How to handle value overflows. This is dependant on the item_class but by default see StructureItem.

  • format_string (String) (defaults to: nil) —

    String to pass to Kernel#sprintf

  • read_conversion (Conversion) (defaults to: nil) —

    Conversion to apply when reading the item from the packet buffer

  • write_conversion (Conversion) (defaults to: nil) —

    Conversion to apply before writing the item to the packet buffer

  • id_value (Object) (defaults to: nil) —

    Set to something other than nil to indicate that this item should be used to identify a buffer as this packet. The id_value should make sense according to the data_type.

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 488

def append_item(name, bit_size, data_type, array_size = nil, endianness = @default_endianness, overflow = :ERROR, format_string = nil, read_conversion = nil, write_conversion = nil, id_value = nil)
  item = super(name, bit_size, data_type, array_size, endianness, overflow)
  packet_define_item(item, format_string, read_conversion, write_conversion, id_value)
end

#buffer=(buffer) ⇒ Object

Set the buffer to be used by the structure. The buffer is copied and thus further modifications to the buffer have no effect on the structure items.

Parameters:

  • buffer (String) —

    Buffer of data to back the stucture items



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# File 'lib/cosmos/packets/packet.rb', line 269

def buffer=(buffer)
  synchronize() do
    begin
      internal_buffer_equals(buffer)
    rescue RuntimeError
      Logger.instance.error "#{@target_name} #{@packet_name} received with actual packet length of #{buffer.length} but defined length of #{@defined_length}"
    end
    @read_conversion_cache.clear if @read_conversion_cache
    process()
  end
end

#check_bit_offsets ⇒ Array<String>

Review bit offset to look for overlapping definitions. This will allow gaps in the packet, but not allow the same bits to be used for multiple variables.

Returns:

  • (Array<String>) —

    Warning messages for big definition overlaps



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# File 'lib/cosmos/packets/packet.rb', line 339

def check_bit_offsets
  expected_next_offset = nil
  previous_item = nil
  warnings = []
  @sorted_items.each do |item|
    if expected_next_offset and (item.bit_offset < expected_next_offset) and !item.overlap
      msg = "Bit definition overlap at bit offset #{item.bit_offset} for packet #{@target_name} #{@packet_name} items #{item.name} and #{previous_item.name}"
      Logger.instance.warn(msg)
      warnings << msg
    end
    expected_next_offset = Packet.next_bit_offset(item)
    previous_item = item
  end
  warnings
end

#check_limits(limits_set = :DEFAULT, ignore_persistence = false) ⇒ Object

Check all the items in the packet against their defined limits. Update their internal limits state and persistence and call the limits_change_callback as necessary.

Parameters:

  • limits_set (Symbol) (defaults to: :DEFAULT) —

    Which limits set to check the item values against.

  • ignore_persistence (Boolean) (defaults to: false) —

    Whether to ignore persistence when checking for out of limits



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# File 'lib/cosmos/packets/packet.rb', line 805

def check_limits(limits_set = :DEFAULT, ignore_persistence = false)
  # If check_limits is being called, then a new packet has arrived and
  # this packet is no longer stale
  # Stored telemetry doesn't affect the current value table and such doesn't affect stale
  if @stale and !@stored
    @stale = false
    set_all_limits_states(nil)
  end

  return unless @limits_items
  @limits_items.each do |item|
    # Verify limits monitoring is enabled for this item
    if item.limits.enabled
      value = read_item(item)

      # Handle state monitoring and value monitoring differently
      if item.states
        handle_limits_states(item, value)
      elsif item.limits.values
        handle_limits_values(item, value, limits_set, ignore_persistence)
      end
    end
  end
end

#clone ⇒ Packet Also known as: dup

Make a light weight clone of this packet. This only creates a new buffer of data and clones the processors. The defined packet items are the same.

Returns:

  • (Packet) —

    A copy of the current packet with a new underlying buffer of data and processors



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# File 'lib/cosmos/packets/packet.rb', line 863

def clone
  packet = super()
  if packet.instance_variable_get("@processors".freeze)
    packet.instance_variable_set("@processors".freeze, packet.processors.clone)
    packet.processors.each do |processor_name, processor|
      packet.processors[processor_name] = processor.clone
    end
  end
  packet.instance_variable_set("@read_conversion_cache".freeze, nil)
  packet.extra = JSON.parse(packet.extra.to_json) if packet.extra # Deep copy using JSON
  packet
end

#config_name ⇒ Object

Calculates a unique hashing sum that changes if the parts of the packet configuration change that could affect the “shape” of the packet. This value is cached and that packet should not be changed if this method is being used



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# File 'lib/cosmos/packets/packet.rb', line 254

def config_name
  return @config_name if @config_name
  string = "#{self.target_name} #{self.packet_name}"
  @sorted_items.each do |item|
    string << " ITEM #{item.name} #{item.bit_offset} #{item.bit_size} #{item.data_type} #{item.array_size} #{item.endianness} #{item.overflow} #{item.states} #{item.read_conversion ? item.read_conversion.class : 'NO_CONVERSION'}"
  end

  # Use the hashing algorithm established by Cosmos::System
  digest = Digest.const_get(System.hashing_algorithm).send('new')
  digest << string
  @config_name = digest.hexdigest
  @config_name
end

#define(item) ⇒ PacketItem

Add an item to the packet by adding it to the items hash. It also resizes the buffer to accomodate the new item.

Parameters:

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 466

def define(item)
  item = super(item)
  update_id_items(item)
  update_limits_items_cache(item)
  item
end

#define_item(name, bit_offset, bit_size, data_type, array_size = nil, endianness = @default_endianness, overflow = :ERROR, format_string = nil, read_conversion = nil, write_conversion = nil, id_value = nil) ⇒ PacketItem

Define an item in the packet. This creates a new instance of the item_class as given in the constructor and adds it to the items hash. It also resizes the buffer to accomodate the new item.

Parameters:

  • name (String) —

    Name of the item. Used by the items hash to retrieve the item.

  • bit_offset (Integer) —

    Bit offset of the item in the raw buffer

  • bit_size (Integer) —

    Bit size of the item in the raw buffer

  • data_type (Symbol) —

    Type of data contained by the item. This is dependant on the item_class but by default see StructureItem.

  • array_size (Integer) (defaults to: nil) —

    Set to a non nil value if the item is to represented as an array.

  • endianness (Symbol) (defaults to: @default_endianness) —

    Endianness of this item. By default the endianness as set in the constructure is used.

  • overflow (Symbol) (defaults to: :ERROR) —

    How to handle value overflows. This is dependant on the item_class but by default see StructureItem.

  • format_string (String) (defaults to: nil) —

    String to pass to Kernel#sprintf

  • read_conversion (Conversion) (defaults to: nil) —

    Conversion to apply when reading the item from the packet buffer

  • write_conversion (Conversion) (defaults to: nil) —

    Conversion to apply before writing the item to the packet buffer

  • id_value (Object) (defaults to: nil) —

    Set to something other than nil to indicate that this item should be used to identify a buffer as this packet. The id_value should make sense according to the data_type.

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 456

def define_item(name, bit_offset, bit_size, data_type, array_size = nil, endianness = @default_endianness, overflow = :ERROR, format_string = nil, read_conversion = nil, write_conversion = nil, id_value = nil)
  item = super(name, bit_offset, bit_size, data_type, array_size, endianness, overflow)
  packet_define_item(item, format_string, read_conversion, write_conversion, id_value)
end

#define_reserved_items ⇒ Object

Define the reserved items on the current telemetry packet



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# File 'lib/cosmos/packets/packet.rb', line 721

def define_reserved_items
  item = define_item('PACKET_TIMESECONDS', 0, 0, :DERIVED, nil, @default_endianness,
                     :ERROR, '%0.6f', PacketTimeSecondsConversion.new)
  item.description = 'COSMOS Packet Time (UTC, Floating point, Unix epoch)'
  item = define_item('PACKET_TIMEFORMATTED', 0, 0, :DERIVED, nil, @default_endianness,
                     :ERROR, nil, PacketTimeFormattedConversion.new)
  item.description = 'COSMOS Packet Time (Local time zone, Formatted string)'
  item = define_item('RECEIVED_TIMESECONDS', 0, 0, :DERIVED, nil, @default_endianness,
                     :ERROR, '%0.6f', ReceivedTimeSecondsConversion.new)
  item.description = 'COSMOS Received Time (UTC, Floating point, Unix epoch)'
  item = define_item('RECEIVED_TIMEFORMATTED', 0, 0, :DERIVED, nil, @default_endianness,
                     :ERROR, nil, ReceivedTimeFormattedConversion.new)
  item.description = 'COSMOS Received Time (Local time zone, Formatted string)'
  item = define_item('RECEIVED_COUNT', 0, 0, :DERIVED, nil, @default_endianness,
                     :ERROR, nil, ReceivedCountConversion.new)
  item.description = 'COSMOS packet received count'
end

#disable_limits(name) ⇒ Object

Disable limits on an item by name

Parameters:

  • name (String) —

    Name of the item to disable limits



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# File 'lib/cosmos/packets/packet.rb', line 749

def disable_limits(name)
  item = get_item(name)
  item.limits.enabled = false
  unless item.limits.state == :STALE
    old_limits_state = item.limits.state
    item.limits.state = nil
    @limits_change_callback.call(self, item, old_limits_state, nil, false) if @limits_change_callback
  end
end

#enable_limits(name) ⇒ Object

Enable limits on an item by name

Parameters:

  • name (String) —

    Name of the item to enable limits



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# File 'lib/cosmos/packets/packet.rb', line 742

def enable_limits(name)
  get_item(name).limits.enabled = true
end

#formatted(value_type = :CONVERTED, indent = 0, buffer = @buffer, ignored = nil) ⇒ String

Create a string that shows the name and value of each item in the packet

Parameters:

  • value_type (Symbol) (defaults to: :CONVERTED) —

    How to convert the item before returning it. Must be one of VALUE_TYPES

  • indent (Integer) (defaults to: 0) —

    Amount to indent before printing the item name

  • buffer (String) (defaults to: @buffer) —

    The binary buffer to write the value to

Returns:

  • (String) —

    String formatted with all the item names and values



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# File 'lib/cosmos/packets/packet.rb', line 705

def formatted(value_type = :CONVERTED, indent = 0, buffer = @buffer, ignored = nil)
  return super(value_type, indent, buffer, ignored)
end

#get_item(name) ⇒ StructureItem

Returns StructureItem or one of its subclasses.

Parameters:

  • name (String) —

    Name of the item to look up in the items Hash

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 494

def get_item(name)
  super(name)
rescue ArgumentError
  raise "Packet item '#{@target_name} #{@packet_name} #{name.upcase}' does not exist"
end

#id_items ⇒ Array<PacketItem>

Id items are used by the identify? method to determine if a raw buffer of data represents this packet.

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 405

def id_items
  @id_items ||= []
end

#identified? ⇒ TrueClass or FalseClass

Indicates if the packet has been identified

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 427

def identified?
  !@target_name.nil? && !@packet_name.nil?
end

#identify?(buffer) ⇒ Boolean

Tries to identify if a buffer represents the currently defined packet. It does this by iterating over all the packet items that were created with an ID value and checking whether that ID value is present at the correct location in the buffer.

Incorrectly sized buffers will still positively identify if there is enough data to match the ID values. This is to allow incorrectly sized packets to still be processed as well as possible given the incorrectly sized data.

Parameters:

  • buffer (String) —

    Raw buffer of binary data

Returns:

  • (Boolean) —

    Whether or not the buffer of data is this packet



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# File 'lib/cosmos/packets/packet.rb', line 204

def identify?(buffer)
  return false unless buffer
  return true unless @id_items

  @id_items.each do |item|
    begin
      value = read_item(item, :RAW, buffer)
    rescue Exception
      value = nil
    end
    return false if item.id_value != value
  end

  true
end

#limits_change_callback=(limits_change_callback) ⇒ Object

Sets the callback object called when a limits state changes

Parameters:

  • limits_change_callback (#call) —

    Object must respond to the call method and take the following arguments: packet (Packet), item (PacketItem), old_limits_state (Symbol), item_value (Object), log_change (Boolean). The current item state can be found by querying the item object: item.limits.state.



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# File 'lib/cosmos/packets/packet.rb', line 325

def limits_change_callback=(limits_change_callback)
  if limits_change_callback
    raise ArgumentError, "limits_change_callback must respond to call" unless limits_change_callback.respond_to?(:call)
    @limits_change_callback = limits_change_callback
  else
    @limits_change_callback = nil
  end
end

#limits_items ⇒ Array<PacketItem>

Returns All items with defined limits.

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 410

def limits_items
  @limits_items ||= []
end

#meta ⇒ Hash<Meta Name, Meta Values>

Returns packet specific metadata

Returns:

  • (Hash<Meta Name, Meta Values>) 


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# File 'lib/cosmos/packets/packet.rb', line 421

def meta
  @meta ||= {}
end

#out_of_limits ⇒ Array<Array<String, String, String, Symbol>>

Return an array of arrays indicating all items in the packet that are out of limits

[[target name, packet name, item name, item limits state], ...]

Returns:



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# File 'lib/cosmos/packets/packet.rb', line 778

def out_of_limits
  items = []
  return items unless @limits_items
  @limits_items.each do |item|
    if (item.limits.enabled && item.limits.state &&
      PacketItemLimits::OUT_OF_LIMITS_STATES.include?(item.limits.state))
      items << [@target_name, @packet_name, item.name, item.limits.state]
    end
  end
  return items
end

#packed? ⇒ Boolean

Checks if the packet has any gaps or overlapped items

Returns:

  • (Boolean) —

    true if the packet has no gaps or overlapped items



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# File 'lib/cosmos/packets/packet.rb', line 358

def packed?
  expected_next_offset = nil
  @sorted_items.each do |item|
    if expected_next_offset and item.bit_offset != expected_next_offset
      return false
    end
    expected_next_offset = Packet.next_bit_offset(item)
  end
  true
end

#packet_time ⇒ Object

Returns @received_time unless a packet item called PACKET_TIME exists that returns a Ruby Time object that represents a different timestamp for the packet



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# File 'lib/cosmos/packets/packet.rb', line 243

def packet_time
  item = @items['PACKET_TIME'.freeze]
  if item
    return read_item(item, :CONVERTED, @buffer)
  else
    return @received_time
  end
end

#processors ⇒ Hash

Returns Hash of processors associated with this packet.

Returns:

  • (Hash) —

    Hash of processors associated with this packet



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# File 'lib/cosmos/packets/packet.rb', line 415

def processors
  @processors ||= {}
end

#read(name, value_type = :CONVERTED, buffer = @buffer) ⇒ Object

Read an item in the packet by name

Parameters:

  • name (String) —

    Name of the item to read

  • value_type (Symbol) (defaults to: :CONVERTED) —

    How to convert the item before returning it. Must be one of VALUE_TYPES

  • buffer (String) (defaults to: @buffer) —

    The binary buffer to read the item from

Returns:

  • The value. :FORMATTED and :WITH_UNITS values are always returned as Strings. :RAW values will match their data_type. :CONVERTED values can be any type.



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# File 'lib/cosmos/packets/packet.rb', line 655

def read(name, value_type = :CONVERTED, buffer = @buffer)
  return super(name, value_type, buffer)
end

#read_all(value_type = :CONVERTED, buffer = @buffer, top = true) ⇒ Array<Array>

Read all items in the packet into an array of arrays

[[item name, item value], ...]

Parameters:

  • top (See Structure#read_all) (defaults to: true)
  • value_type (Symbol) (defaults to: :CONVERTED) —

    How to convert the item before returning it. Must be one of VALUE_TYPES

  • buffer (String) (defaults to: @buffer) —

    The binary buffer to write the value to

Returns:

  • (Array<Array>) —

    Array of two element arrays containing the item name as element 0 and item value as element 1.



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# File 'lib/cosmos/packets/packet.rb', line 676

def read_all(value_type = :CONVERTED, buffer = @buffer, top = true)
  return super(value_type, buffer, top)
end

#read_all_with_limits_states(value_type = :CONVERTED, buffer = @buffer) ⇒ Array<String, Object, Symbol|nil>

Read all items in the packet into an array of arrays

[[item name, item value], [item limits state], ...]

Parameters:

  • value_type (Symbol) (defaults to: :CONVERTED) —

    How to convert the item before returning it. Must be one of VALUE_TYPES

  • buffer (String) (defaults to: @buffer) —

    The binary buffer to write the value to

Returns:

  • (Array<String, Object, Symbol|nil>) —

    Returns an Array consisting of [item name, item value, item limits state] where the item limits state can be one of Limits::LIMITS_STATES



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# File 'lib/cosmos/packets/packet.rb', line 688

def read_all_with_limits_states(value_type = :CONVERTED, buffer = @buffer)
  result = nil
  synchronize_allow_reads(true) do
    result = read_all(value_type, buffer, false).map! do |array|
      array << @items[array[0]].limits.state
    end
  end
  return result
end

#read_id_values(buffer) ⇒ Array

Reads the values from a buffer at the position of each id_item defined in the packet.

Parameters:

  • buffer (String) —

    Raw buffer of binary data

Returns:

  • (Array) —

    Array of read id values in order



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# File 'lib/cosmos/packets/packet.rb', line 225

def read_id_values(buffer)
  return [] unless buffer
  return [] unless @id_items
  values = []
  
  @id_items.each do |item|
    begin
      values << read_item(item, :RAW, buffer)
    rescue Exception
      values << nil
    end
  end
  
  values
end

#read_item(item, value_type = :CONVERTED, buffer = @buffer) ⇒ Object

Read an item in the packet

Parameters:

  • item (PacketItem) —

    Instance of PacketItem or one of its subclasses

  • value_type (Symbol) (defaults to: :CONVERTED) —

    How to convert the item before returning it. Must be one of VALUE_TYPES

  • buffer (String) (defaults to: @buffer) —

    The binary buffer to read the item from

Returns:

  • The value. :FORMATTED and :WITH_UNITS values are always returned as Strings. :RAW values will match their data_type. :CONVERTED values can be any type.



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# File 'lib/cosmos/packets/packet.rb', line 509

def read_item(item, value_type = :CONVERTED, buffer = @buffer)
  value = super(item, :RAW, buffer)
  derived_raw = false
  if item.data_type == :DERIVED && value_type == :RAW
    value_type = :CONVERTED
    derived_raw = true
  end
  case value_type
  when :RAW
    # Done above
  when :CONVERTED, :FORMATTED, :WITH_UNITS
    if item.read_conversion
      using_cached_value = false

      check_cache = buffer.equal?(@buffer)
      if check_cache and @read_conversion_cache
        synchronize_allow_reads() do
          if @read_conversion_cache[item]
            value = @read_conversion_cache[item]

            # Make sure cached value is not modified by anyone by creating
            # a deep copy
            if String === value
              value = value.clone
            elsif Array === value
              value = Marshal.load(Marshal.dump(value))
            end

            using_cached_value = true
          end
        end
      end

      unless using_cached_value
        if item.array_size
          value.map! do |val, index|
            item.read_conversion.call(val, self, buffer)
          end
        else
          value = item.read_conversion.call(value, self, buffer)
        end
        if check_cache
          synchronize_allow_reads() do
            @read_conversion_cache ||= {}
            @read_conversion_cache[item] = value

            # Make sure cached value is not modified by anyone by creating
            # a deep copy
            if String === value
              value = value.clone
            elsif Array === value
              value = Marshal.load(Marshal.dump(value))
            end
          end
        end
      end
    end

    # Derived raw values perform read_conversions but nothing else
    return value if derived_raw

    # Convert from value to state if possible
    if item.states
      if Array === value
        value = value.map do |val, index|
          if item.states.key(val)
            item.states.key(val)
          elsif item.states.values.include?(CATCH_ALL_STATE)
            item.states.key(CATCH_ALL_STATE)
          else
            apply_format_string_and_units(item, val, value_type)
          end
        end
      else
        state_value = item.states.key(value)
        if state_value
          value = state_value
        elsif item.states.values.include?(CATCH_ALL_STATE)
          value = item.states.key(CATCH_ALL_STATE)
        else
          value = apply_format_string_and_units(item, value, value_type)
        end
      end
    else
      if Array === value
        value = value.map do |val, index|
          apply_format_string_and_units(item, val, value_type)
        end
      else
        value = apply_format_string_and_units(item, value, value_type)
      end
    end
  else
    raise ArgumentError, "Unknown value type on read: #{value_type}"
  end
  return value
end

#reset ⇒ Object

Reset temporary packet data This includes packet received time, received count, and processor state



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# File 'lib/cosmos/packets/packet.rb', line 839

def reset
  # The SYSTEM META packet is a special case that does not get reset
  return if @target_name == 'SYSTEM' && @packet_name == 'META'

  @received_time = nil
  @received_count = 0
  @stored = false
  @extra = nil
  if @read_conversion_cache
    synchronize() do
      @read_conversion_cache.clear
    end
  end
  return unless @processors
  @processors.each do |processor_name, processor|
    processor.reset
  end
end

#restore_defaults(buffer = @buffer, skip_item_names = nil) ⇒ Object

Restore all items in the packet to their default value

Parameters:

  • buffer (String) (defaults to: @buffer) —

    Raw buffer of binary data

  • skip_item_names (Array) (defaults to: nil) —

    Array of item names to skip



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# File 'lib/cosmos/packets/packet.rb', line 713

def restore_defaults(buffer = @buffer, skip_item_names = nil)
  upcase_skip_item_names = skip_item_names.map(&:upcase) if skip_item_names
  @sorted_items.each do |item|
    write_item(item, item.default, :CONVERTED, buffer) unless (skip_item_names and upcase_skip_item_names.include?(item.name))
  end
end

#set_all_limits_states(state) ⇒ Object

Set the limits state for all items to the given state

Parameters:

  • state (Symbol) —

    Must be one of PacketItemLimits::LIMITS_STATES



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# File 'lib/cosmos/packets/packet.rb', line 793

def set_all_limits_states(state)
  @sorted_items.each {|item| item.limits.state = state}
end

#set_received_time_fast(received_time) ⇒ Object

Sets the received time of the packet (without cloning)

Parameters:

  • received_time (Time) —

    Time this packet was received



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# File 'lib/cosmos/packets/packet.rb', line 284

def set_received_time_fast(received_time)
  @received_time = received_time
  @received_time.freeze if @received_time
  if @read_conversion_cache
    synchronize() do
      @read_conversion_cache.clear
    end
  end
end

#set_stale ⇒ Object

Sets the overall packet stale state to true and sets each packet item limits state to :STALE.



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# File 'lib/cosmos/packets/packet.rb', line 832

def set_stale
  @stale = true
  set_all_limits_states(:STALE)
end

#to_config(cmd_or_tlm) ⇒ Object 



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# File 'lib/cosmos/packets/packet.rb', line 897

def to_config(cmd_or_tlm)
  config = ''

  if cmd_or_tlm == :TELEMETRY
    config << "TELEMETRY #{self.target_name.to_s.quote_if_necessary} #{self.packet_name.to_s.quote_if_necessary} #{@default_endianness} \"#{self.description}\"\n"
  else
    config << "COMMAND #{self.target_name.to_s.quote_if_necessary} #{self.packet_name.to_s.quote_if_necessary} #{@default_endianness} \"#{self.description}\"\n"
  end
  config << "  ALLOW_SHORT\n" if self.short_buffer_allowed
  config << "  HAZARDOUS #{self.hazardous_description.to_s.quote_if_necessary}\n" if self.hazardous
  config << "  DISABLE_MESSAGES\n" if self.messages_disabled
  if self.disabled
    config << "  DISABLED\n"
  elsif self.hidden
    config << "  HIDDEN\n"
  end

  if @processors
    @processors.each do |processor_name, processor|
      config << processor.to_config
    end
  end

  if @meta
    @meta.each do |key, values|
      config << "  META #{key.to_s.quote_if_necessary} #{values.map {|a| a..to_s.quote_if_necessary}.join(" ")}\n"
    end
  end

  # Items with derived items last
  self.sorted_items.each do |item|
    if item.data_type != :DERIVED
      config << item.to_config(cmd_or_tlm, @default_endianness)
    end
  end
  self.sorted_items.each do |item|
    if item.data_type == :DERIVED
      unless RESERVED_ITEM_NAMES.include?(item.name)
        config << item.to_config(cmd_or_tlm, @default_endianness)
      end
    end
  end

  config
end

#update_id_items(item) ⇒ Object 



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# File 'lib/cosmos/packets/packet.rb', line 877

def update_id_items(item)
  if item.id_value
    @id_items ||= []
    # Add to Id Items
    unless @id_items.empty?
      last_item = @id_items[-1]
      @id_items << item
      # If the current item or last item have a negative offset then we have
      # to re-sort. We also re-sort if the current item is less than the last
      # item because we are inserting.
      if last_item.bit_offset <= 0 or item.bit_offset <= 0 or item.bit_offset < last_item.bit_offset
        @id_items = @id_items.sort
      end
    else
      @id_items << item
    end
  end
  item
end

#update_limits_items_cache(item) ⇒ Object

Add an item to the limits items cache if necessary. You MUST call this after adding limits to an item This is an optimization so we don’t have to iterate through all the items when checking for limits.



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# File 'lib/cosmos/packets/packet.rb', line 763

def update_limits_items_cache(item)
  if item.limits.values || item.state_colors
    @limits_items ||= []
    @limits_items_hash ||= {}
    unless @limits_items_hash[item]
      @limits_items << item
      @limits_items_hash[item] = true
    end
  end
end

#write(name, value, value_type = :CONVERTED, buffer = @buffer) ⇒ Object

Write an item in the packet by name

Parameters:

  • name (String) —

    Name of the item to write

  • value (Object) —

    Value based on the item definition. This could be a string, integer, float, or array of values.

  • value_type (Symbol) (defaults to: :CONVERTED) —

    How to convert the item before returning it. Must be one of VALUE_TYPES

  • buffer (String) (defaults to: @buffer) —

    The binary buffer to write the value to



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# File 'lib/cosmos/packets/packet.rb', line 665

def write(name, value, value_type = :CONVERTED, buffer = @buffer)
  super(name, value, value_type, buffer)
end

#write_item(item, value, value_type = :CONVERTED, buffer = @buffer) ⇒ Object

Write an item in the packet

Parameters:

  • item (PacketItem) —

    Instance of PacketItem or one of its subclasses

  • value (Object) —

    Value based on the item definition. This could be a string, integer, float, or array of values.

  • value_type (Symbol) (defaults to: :CONVERTED) —

    How to convert the item before returning it. Must be one of VALUE_TYPES

  • buffer (String) (defaults to: @buffer) —

    The binary buffer to write the value to



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# File 'lib/cosmos/packets/packet.rb', line 613

def write_item(item, value, value_type = :CONVERTED, buffer = @buffer)
  case value_type
  when :RAW
    super(item, value, value_type, buffer)
  when :CONVERTED
    if item.states
      # Convert from state to value if possible
      state_value = item.states[value.to_s.upcase]
      value = state_value if state_value
    end
    if item.write_conversion
      value = item.write_conversion.call(value, self, buffer)
    else
      raise "Cannot write DERIVED item without a write conversion" if item.data_type == :DERIVED
    end
    begin
      super(item, value, :RAW, buffer) unless item.data_type == :DERIVED
    rescue ArgumentError => err
      if item.states and String === value and err.message =~ /invalid value for/
        raise "Unknown state #{value} for #{item.name}"
      else
        raise err
      end
    end
  when :FORMATTED, :WITH_UNITS
    raise ArgumentError, "Invalid value type on write: #{value_type}"
  else
    raise ArgumentError, "Unknown value type on write: #{value_type}"
  end
  if @read_conversion_cache
    synchronize() do
      @read_conversion_cache.clear
    end
  end
end