Class: Kafka::Protocol::RecordBatch

Inherits:
Object
  • Object
show all
Defined in:
lib/kafka/protocol/record_batch.rb

Constant Summary collapse

MAGIC_BYTE = 
2
RECORD_BATCH_OVERHEAD =

The size of metadata before the real record data

49
CODEC_ID_MASK =

Masks to extract information from attributes

0b00000111
IN_TRANSACTION_MASK = 
0b00010000
IS_CONTROL_BATCH_MASK = 
0b00100000
TIMESTAMP_TYPE_MASK = 
0b001000

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(records: [], first_offset: 0, first_timestamp: Time.now, partition_leader_epoch: 0, codec_id: 0, in_transaction: false, is_control_batch: false, last_offset_delta: 0, producer_id: -1,, producer_epoch: 0, first_sequence: 0, max_timestamp: Time.now) ⇒ RecordBatch

Returns a new instance of RecordBatch.



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# File 'lib/kafka/protocol/record_batch.rb', line 20

def initialize(
    records: [],
    first_offset: 0,
    first_timestamp: Time.now,
    partition_leader_epoch: 0,
    codec_id: 0,
    in_transaction: false,
    is_control_batch: false,
    last_offset_delta: 0,
    producer_id: -1,
    producer_epoch: 0,
    first_sequence: 0,
    max_timestamp: Time.now
)
  @records = Array(records)
  @first_offset = first_offset
  @first_timestamp = first_timestamp
  @codec_id = codec_id

  # Records verification
  @last_offset_delta = last_offset_delta
  @max_timestamp = max_timestamp

  # Transaction information
  @producer_id = producer_id
  @producer_epoch = producer_epoch

  @first_sequence = first_sequence
  @partition_leader_epoch = partition_leader_epoch
  @in_transaction = in_transaction
  @is_control_batch = is_control_batch

  mark_control_record
end

Instance Attribute Details

#codec_id ⇒ Object

Returns the value of attribute codec_id.



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# File 'lib/kafka/protocol/record_batch.rb', line 18

def codec_id
  @codec_id
end

#first_offset ⇒ Object (readonly)

Returns the value of attribute first_offset.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def first_offset
  @first_offset
end

#first_sequence ⇒ Object (readonly)

Returns the value of attribute first_sequence.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def first_sequence
  @first_sequence
end

#first_timestamp ⇒ Object (readonly)

Returns the value of attribute first_timestamp.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def first_timestamp
  @first_timestamp
end

#in_transaction ⇒ Object (readonly)

Returns the value of attribute in_transaction.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def in_transaction
  @in_transaction
end

#is_control_batch ⇒ Object (readonly)

Returns the value of attribute is_control_batch.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def is_control_batch
  @is_control_batch
end

#last_offset_delta ⇒ Object (readonly)

Returns the value of attribute last_offset_delta.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def last_offset_delta
  @last_offset_delta
end

#max_timestamp ⇒ Object (readonly)

Returns the value of attribute max_timestamp.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def max_timestamp
  @max_timestamp
end

#partition_leader_epoch ⇒ Object (readonly)

Returns the value of attribute partition_leader_epoch.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def partition_leader_epoch
  @partition_leader_epoch
end

#producer_epoch ⇒ Object (readonly)

Returns the value of attribute producer_epoch.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def producer_epoch
  @producer_epoch
end

#producer_id ⇒ Object (readonly)

Returns the value of attribute producer_id.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def producer_id
  @producer_id
end

#records ⇒ Object (readonly)

Returns the value of attribute records.



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# File 'lib/kafka/protocol/record_batch.rb', line 16

def records
  @records
end

Class Method Details

.decode(decoder) ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 151

def self.decode(decoder)
  first_offset = decoder.int64

  record_batch_raw = decoder.bytes
  record_batch_decoder = Decoder.from_string(record_batch_raw)

  partition_leader_epoch = record_batch_decoder.int32
  # Currently, the magic byte is used to distingush legacy MessageSet and
  # RecordBatch. Therefore, we don't care about magic byte here yet.
  _magic_byte = record_batch_decoder.int8
  _crc = record_batch_decoder.int32

  attributes = record_batch_decoder.int16
  codec_id = attributes & CODEC_ID_MASK
  in_transaction = (attributes & IN_TRANSACTION_MASK) > 0
  is_control_batch = (attributes & IS_CONTROL_BATCH_MASK) > 0
  log_append_time = (attributes & TIMESTAMP_TYPE_MASK) != 0

  last_offset_delta = record_batch_decoder.int32
  first_timestamp = Time.at(record_batch_decoder.int64 / 1000)
  max_timestamp = Time.at(record_batch_decoder.int64 / 1000)

  producer_id = record_batch_decoder.int64
  producer_epoch = record_batch_decoder.int16
  first_sequence = record_batch_decoder.int32

  records_array_length = record_batch_decoder.int32
  records_array_raw = record_batch_decoder.read(
    record_batch_raw.size - RECORD_BATCH_OVERHEAD
  )
  if codec_id != 0
    codec = Compression.find_codec_by_id(codec_id)
    records_array_raw = codec.decompress(records_array_raw)
  end

  records_array_decoder = Decoder.from_string(records_array_raw)
  records_array = []
  until records_array_decoder.eof?
    record = Record.decode(records_array_decoder)
    record.offset = first_offset + record.offset_delta
    record.create_time = log_append_time && max_timestamp ? max_timestamp : first_timestamp + record.timestamp_delta
    records_array << record
  end

  raise InsufficientDataMessage if records_array.length != records_array_length

  new(
    records: records_array,
    first_offset: first_offset,
    first_timestamp: first_timestamp,
    partition_leader_epoch: partition_leader_epoch,
    in_transaction: in_transaction,
    is_control_batch: is_control_batch,
    last_offset_delta: last_offset_delta,
    producer_id: producer_id,
    producer_epoch: producer_epoch,
    first_sequence: first_sequence,
    max_timestamp: max_timestamp
  )
rescue EOFError
  raise InsufficientDataMessage, 'Partial trailing record detected!'
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 139

def ==(other)
  records == other.records &&
    first_offset == other.first_offset &&
    partition_leader_epoch == other.partition_leader_epoch &&
    in_transaction == other.in_transaction &&
    is_control_batch == other.is_control_batch &&
    last_offset_delta == other.last_offset_delta &&
    producer_id == other.producer_id &&
    producer_epoch == other.producer_epoch &&
    first_sequence == other.first_sequence
end

#attributes ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 63

def attributes
  0x0000 | @codec_id |
    (@in_transaction ? IN_TRANSACTION_MASK : 0x0) |
    (@is_control_batch ? IS_CONTROL_BATCH_MASK : 0x0)
end

#compressed? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/kafka/protocol/record_batch.rb', line 121

def compressed?
  @codec_id != 0
end

#encode(encoder) ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 69

def encode(encoder)
  encoder.write_int64(@first_offset)

  record_batch_buffer = StringIO.new
  record_batch_encoder = Encoder.new(record_batch_buffer)

  record_batch_encoder.write_int32(@partition_leader_epoch)
  record_batch_encoder.write_int8(MAGIC_BYTE)

  body = encode_record_batch_body
  crc = Digest::CRC32c.checksum(body)

  record_batch_encoder.write_int32(crc)
  record_batch_encoder.write(body)

  encoder.write_bytes(record_batch_buffer.string)
end

#encode_record_array ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 112

def encode_record_array
  buffer = StringIO.new
  encoder = Encoder.new(buffer)
  @records.each do |record|
    record.encode(encoder)
  end
  buffer.string
end

#encode_record_batch_body ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 87

def encode_record_batch_body
  buffer = StringIO.new
  encoder = Encoder.new(buffer)

  encoder.write_int16(attributes)
  encoder.write_int32(@last_offset_delta)
  encoder.write_int64((@first_timestamp.to_f * 1000).to_i)
  encoder.write_int64((@max_timestamp.to_f * 1000).to_i)

  encoder.write_int64(@producer_id)
  encoder.write_int16(@producer_epoch)
  encoder.write_int32(@first_sequence)

  encoder.write_int32(@records.length)

  records_array = encode_record_array
  if compressed?
    codec = Compression.find_codec_by_id(@codec_id)
    records_array = codec.compress(records_array)
  end
  encoder.write(records_array)

  buffer.string
end

#fulfill_relative_data ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 125

def fulfill_relative_data
  first_record = records.min_by { |record| record.create_time }
  @first_timestamp = first_record.nil? ? Time.now : first_record.create_time

  last_record = records.max_by { |record| record.create_time }
  @max_timestamp = last_record.nil? ? Time.now : last_record.create_time

  records.each_with_index do |record, index|
    record.offset_delta = index
    record.timestamp_delta = (record.create_time - first_timestamp).to_i
  end
  @last_offset_delta = records.length - 1
end

#last_offset ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 59

def last_offset
  @first_offset + @last_offset_delta
end

#mark_control_record ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 214

def mark_control_record
  if in_transaction && is_control_batch
    record = @records.first
    record.is_control_record = true unless record.nil?
  end
end

#size ⇒ Object 



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# File 'lib/kafka/protocol/record_batch.rb', line 55

def size
  @records.size
end