lib/bson/time.rb
# frozen_string_literal: true
# rubocop:todo all
# Copyright (C) 2009-2020 MongoDB Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
module BSON
# Injects behaviour for encoding and decoding time values to
# and from raw bytes as specified by the BSON spec.
#
# @note
# Ruby time can have nanosecond precision:
# +Time.utc(2020, 1, 1, 0, 0, 0, 999_999_999/1000r)+
# +Time#usec+ returns the number of microseconds in the time, and
# if the time has nanosecond precision the sub-microsecond part is
# truncated (the value is floored to the nearest millisecond).
# MongoDB only supports millisecond precision; we truncate the
# sub-millisecond part of microseconds (floor to the nearest millisecond).
# Note that if a time is constructed from a floating point value,
# the microsecond value may round to the starting floating point value
# but due to flooring, the time after serialization may end up to
# be different than the starting floating point value.
# It is recommended that time calculations use integer math only.
#
# @see http://bsonspec.org/#/specification
#
# @since 2.0.0
module Time
# A time is type 0x09 in the BSON spec.
#
# @since 2.0.0
BSON_TYPE = ::String.new(9.chr, encoding: BINARY).freeze
# Get the time as encoded BSON.
#
# @note The time is floored to the nearest millisecond.
#
# @example Get the time as encoded BSON.
# Time.new(2012, 1, 1, 0, 0, 0).to_bson
#
# @return [ BSON::ByteBuffer ] The buffer with the encoded object.
#
# @see http://bsonspec.org/#/specification
#
# @since 2.0.0
def to_bson(buffer = ByteBuffer.new)
value = _bson_to_i * 1000 + usec.divmod(1000).first
buffer.put_int64(value)
end
# Converts this object to a representation directly serializable to
# Extended JSON (https://github.com/mongodb/specifications/blob/master/source/extended-json.rst).
#
# @note The time is floored to the nearest millisecond.
#
# @option opts [ nil | :relaxed | :legacy ] :mode Serialization mode
# (default is canonical extended JSON)
#
# @return [ Hash ] The extended json representation.
def as_extended_json(**options)
utc_time = utc
if options[:mode] == :relaxed && (1970..9999).include?(utc_time.year)
if utc_time.usec != 0
if utc_time.respond_to?(:floor)
# Ruby 2.7+
utc_time = utc_time.floor(3)
else
utc_time -= utc_time.usec.divmod(1000).last.to_r / 1000000
end
{'$date' => utc_time.strftime('%Y-%m-%dT%H:%M:%S.%LZ')}
else
{'$date' => utc_time.strftime('%Y-%m-%dT%H:%M:%SZ')}
end
else
sec = utc_time._bson_to_i
msec = utc_time.usec.divmod(1000).first
{'$date' => {'$numberLong' => (sec * 1000 + msec).to_s}}
end
end
def _bson_to_i
# Workaround for JRuby's #to_i rounding negative timestamps up
# rather than down (https://github.com/jruby/jruby/issues/6104)
if BSON::Environment.jruby?
(self - usec.to_r/1000000).to_i
else
to_i
end
end
module ClassMethods
# Deserialize UTC datetime from BSON.
#
# @param [ ByteBuffer ] buffer The byte buffer.
#
# @option options [ nil | :bson ] :mode Decoding mode to use.
#
# @return [ Time ] The decoded UTC datetime.
#
# @see http://bsonspec.org/#/specification
#
# @since 2.0.0
def from_bson(buffer, **options)
seconds, fragment = Int64.from_bson(buffer, mode: nil).divmod(1000)
at(seconds, fragment * 1000).utc
end
end
# Register this type when the module is loaded.
#
# @since 2.0.0
Registry.register(BSON_TYPE, ::Time)
end
# Enrich the core Time class with this module.
#
# @since 2.0.0
::Time.send(:include, Time)
::Time.send(:extend, Time::ClassMethods)
end