Class: Neo4j::Driver::PackStream::Packer

Inherits:
Object
  • Object
show all
Includes:
Markers
Defined in:
lib/neo4j/driver/packstream/packer.rb

Overview

PackStream Packer - serializes Ruby objects to PackStream binary format Based on https://neo4j.com/docs/bolt/current/packstream/

Constant Summary

Constants included from Markers

Markers::BYTES_16, Markers::BYTES_32, Markers::BYTES_8, Markers::FALSE, Markers::FLOAT_64, Markers::INT_16, Markers::INT_32, Markers::INT_64, Markers::INT_8, Markers::LIST_16, Markers::LIST_32, Markers::LIST_8, Markers::MAP_16, Markers::MAP_32, Markers::MAP_8, Markers::NULL, Markers::STRING_16, Markers::STRING_32, Markers::STRING_8, Markers::STRUCT_16, Markers::STRUCT_8, Markers::TINY_LIST, Markers::TINY_MAP, Markers::TINY_STRING, Markers::TINY_STRUCT, Markers::TRUE, Markers::UUID

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(protocol) ⇒ Packer

Returns a new instance of Packer.



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# File 'lib/neo4j/driver/packstream/packer.rb', line 17

def initialize(protocol)
  @buffer = String.new(encoding: Encoding::BINARY)
  @use_utc_datetime = false
  @protocol = protocol
end

Instance Attribute Details

#use_utc_datetime ⇒ Object

When true, datetimes are packed as the UTC-seconds Bolt 5.0+ structures (0x49 / 0x69) instead of the legacy local-seconds variants (0x46 / 0x66). Connection sets this after a successful handshake negotiates Bolt 5.0+; ignored on 4.x.



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# File 'lib/neo4j/driver/packstream/packer.rb', line 15

def use_utc_datetime
  @use_utc_datetime
end

Instance Method Details

#bytes ⇒ Object 



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# File 'lib/neo4j/driver/packstream/packer.rb', line 89

def bytes
  @buffer
end

#pack(value) ⇒ Object 



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# File 'lib/neo4j/driver/packstream/packer.rb', line 23

def pack(value)
  case value
  when nil
    pack_null
  when true, false
    pack_boolean(value)
  when Integer
    pack_integer(value)
  when Float
    pack_float(value)
  when String
    # Pack binary strings as BYTES, text strings as STRING
    value.encoding == Encoding::BINARY ? pack_bytes(value) : pack_string(value)
  when Symbol
    pack_string(value.to_s)
  when Hash
    # Check Hash before Enumerable since Hash is also Enumerable
    pack_map(value)
  when Types::Node, Types::Relationship, Types::Path, Types::UnsupportedType
    # Graph types are not valid query parameters; neither is an
    # UnsupportedType (a value the driver couldn't materialise — it
    # must not be sent back to the server). Reject before the Enumerable
    # branch since Path includes Enumerable.
    Exceptions::ClientException.unable_to_convert(value)
  when Array, Set, Range
    # Known sized collections — pack_list uses #size, which is O(1) here.
    pack_list(value)
  when Enumerable
    # Generic Enumerable (lazy enumerators, custom collections) — materialise
    # so #size is well-defined.
    pack_list(value.to_a)
  when ::DateTime, ::Time
    # Check DateTime before Date — DateTime < Date in Ruby, so the
    # Date branch would match first and pack away the time component.
    pack_datetime(value)
  when ::Date
    # Pack Ruby Date as Neo4j Date structure
    pack_date(value)
  when Types::LocalDateTime
    pack_local_datetime(value)
  when Types::LocalTime
    pack_local_time(value)
  when Types::OffsetTime
    pack_offset_time(value)
  when Types::Point
    pack_point(value)
  when Types::Duration
    pack_duration(value)
  when Types::UUID
    # A PackStream V2 type: only the negotiated protocol decides whether
    # it can be sent — V61 packs it, every earlier version rejects it.
    @protocol.pack_uuid(self, value)
  else
    Exceptions::ClientException.unable_to_convert(value)
  end
  self
end

#pack_message(structure) ⇒ Object

Serialise a Bolt protocol message (a PackStream::Structure) onto the buffer. Distinct from #pack so the user-value path doesn't carry knowledge of the wire-level Structure type.



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# File 'lib/neo4j/driver/packstream/packer.rb', line 84

def pack_message(structure)
  pack_structure(structure)
  self
end

#pack_uuid_value(value) ⇒ Object

PackStream V2 UUID (Bolt 6.1+): marker 0xE0 + 16 raw bytes. Called by Protocol::V61#pack_uuid — every earlier protocol rejects a UUID instead, so this is only reached once 6.1 is negotiated.



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# File 'lib/neo4j/driver/packstream/packer.rb', line 101

def pack_uuid_value(value)
  @buffer << [UUID].pack('C')
  @buffer << [value.to_s.delete('-')].pack('H*')
end

#reset ⇒ Object 



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# File 'lib/neo4j/driver/packstream/packer.rb', line 93

def reset
  @buffer.clear
  self
end