Purpose

The timestamp extension (type -1) provides nanosecond precision time handling for Time objects.

References

Concepts

Timestamp formats

Example 1. MessagePack automatically selects the appropriate format
Timestamp32  - 4 bytes (seconds only, 32-bit)
              Used when: nanoseconds == 0 and
                         seconds fit in 32 bits

Timestamp64  - 8 bytes (seconds + nanoseconds)
              Used when: nanoseconds != 0 and
                         timestamp fits in 64 bits

Timestamp96 - 12 bytes (seconds + nanoseconds, 96-bit)
              Used when: timestamp requires 96 bits

Using timestamp with Time 

factory.register_type(-1, Time,
  packer: Messagepack::Time::Packer,
  unpacker: Messagepack::Time::Unpacker
)

Where,

  • -1 is the reserved type ID for timestamps

  • Messagepack::Time::Packer handles serialization with nanosecond precision

  • Messagepack::Time::Unpacker handles deserialization

Examples

Example 2. Timestamp serialization examples
factory = Messagepack::Factory.new
factory.register_type(-1, Time,
  packer: Messagepack::Time::Packer,
  unpacker: Messagepack::Time::Unpacker
)

# Current time with nanosecond precision
now = Time.now
binary = factory.pack(now)
restored = factory.unpack(binary)
puts restored.tv_nsec # Nanoseconds preserved

# Historical date
time = Time.utc(2020, 1, 1, 12, 30, 45)
binary = factory.pack(time)
puts binary.size # => 6 (fixext4 format)

# Future date with nanoseconds
future = Time.utc(2100, 6, 15, 0, 0, 0, 123456789)
binary = factory.pack(future)
puts binary.size # => 15 (ext8 with timestamp96)
The default factory automatically includes the timestamp extension for Time objects. You don’t need to register it unless you create a custom factory.