proto

Lightweight and fast serialization library for Scala 2/3 based on Protocol Buffers with macros magic.

Motivation

Serialization library for Scala that can be used either for long term store models and short term models. With easy to migrate possibility.

• Lightweight
• Fast
• Protocol Buffers compatible
• No .proto files
• No model convertation
• Type safe
• Serialization/deserialization without changes in models
• Possibility to use specific types in model

Install

Add dependency:

libraryDependencies += "io.github.zero-deps" %% "proto" % "latest.integration"

Dependency as a git-submodule is also supported.

Benchmark #1

data		library	scala-2	scala-3
data	decode	java	44079.139	38979.697
data	decode	jackson	176941.468	188555.562
data	decode	jsoniter-scala	483788.001	no support for Scala 3
data	decode	boopickle	2885610.648	no support for Scala 3
data	decode	proto	3383845.458	3776688.591
data	decode	scalapb	3270691.564	3893847.420

data		library	scala-2	scala-3
data	encode	java	220444.268	217484.396
data	encode	jackson	431318.803	384863.249
data	encode	jsoniter-scala	1054650.233	no support for Scala 3
data	encode	boopickle	1520834.519	no support for Scala 3
data	encode	proto	3186951.441	2965427.382
data	encode	scalapb	3628779.864	3972905.402

data		library	scala-2	scala-3
msg	decode	jsoniter-scala	3486552.303	no support for Scala 3
msg	decode	proto	5825174.170	6395557.251
msg	decode	scalapb	4898257.671	6902064.854

data		library	scala-2	scala-3
msg	encode	jsoniter-scala	6372602.760	no support for Scala 3
msg	encode	proto	6487748.959	6745673.393
msg	encode	scalapb	9202135.451	9056962.541

environment

Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz
16 GB 2133 MHz LPDDR3
Java 15

run benchmark

sbt
project bench
++ 3.0.0
jmh:run -i 2 -wi 1 -f1 -t1

Benchmark #2

data		library	scala-3
data	decode	java	92130,460
data	decode	jackson	517036,354
data	decode	proto	6716619,956

data		library	scala-3
data	encode	java	537462,511
data	encode	jackson	882065,311
data	encode	proto	9380874,587

data		library	scala-3
msg	decode	proto	11733555,275

data		library	scala-3
msg	encode	proto	18486833,582

environment

Apple M1
16 GB
Java 21

run benchmark

sbt
project bench
++ 3.0.0
jmh:run -i 2 -wi 1 -f1 -t1

Usage

You can pick one of the way how to define field number:

• with annotation @proto.N and use caseCodecAuto
• explicitly specify nums caseCodecNums(Symbol("field1")->1, Symbol("field2")->2)
• field numbers by index caseCodecIdx

You can use annotation @proto.RestrictedN to restrict usage of specified field numbers. Can be used with classes or traits.

import scala.collection.immutable.TreeMap
import proto.{encode, decode, N}
import proto.{caseCodecIdx, caseCodecNums, caseCodecAuto}

final case class VectorClock(versions: TreeMap[String, Long])
@RestrictedN(3,4)
final case class Equipment(@N(1) id: String, @N(2) tpe: String)
final case class Car(id: String, color: Int, equipment: List[Equipment], vc: VectorClock)

implicit val tuple2Codec = caseCodecIdx[Tuple2[String, Long]] //codec for TreeMap[String, Long]

implicit val vectorClockCodec = caseCodecIdx[VectorClock]
implicit val equipmentCodec = caseCodecAuto[Equipment]
implicit val carCodec = caseCodecNums[Car]('id->1, 'color->4, 'equipment->2, 'vc->3)

val vc = VectorClock(versions=TreeMap.empty)
val equipment = List(Equipment(id="1", tpe="123"), Equipment(id="2", tpe="456"))
val car = Car(id="1", color=16416882, equipment=equipment, vc=vc)
//encode
val bytes: Array[Byte] = encode(car)
//decode
val car2: Car = decode[Car](bytes)

More examples in testing.scala