JUGNsk Meetup#10. Олег Докука: "Multiplayer Pac-Man with RSocket"

Работаете с микросервисами? Раздражает медленный REST? Надоел ненадежный gRPC? Нужно быстрое клиент-серверное взаимодействие, но не хочется изобретать свой WS-протокол? Решение есть, и это RSocket. RSocket — новый протокол уровня приложений с поддержкой Reactive Streams, способный сделать вашу систему быстрой, масштабируемой и отказоустойчивой. Приходите узнать, почему RSocket — это будущее межсервисных взаимодействий.

Из этого доклада вы узнаете, почему RSocket — новаторское решение для межсервисных взаимодействий. Увидите, как создать современный мультиплеерный Pac-Man с помощью этой замечательной технологии. Доклад покажет, как улучшить gRPC с помощью RSocket и почему стоит начать использовать RSocket уже сегодня.

Transcript

1. MULTIPLAYER PAC-MAN WITH RSOCKET @OlehDokuka @netifi_inc
2. Oleh Dokuka • WORK FOR NETIFI • REACTIVE GEEK • REACTOR 3 CONTRIBUTOR • BOOKS AUTHOR • LOCAL COMMUNITY BUILDER @OlehDokuka
4. Agenda • DEFINE PROBLEM • COMPARE PROTOCOLS • HAVE FUN • DEFINE THE BEST PROTOCOL
5. MULTIPLAYER REQUIREMENTS
6. Step 0: Load Step 0: Load
7. Step 1: Setup
8. Step 2:Location
9. Step 3: Updates
10. Step 3: Updates 100. Player 1 88. Player 3 80. Player 5 75. Player 2 68. Player 6 30. Player 4 7. Player 7 Scoreboard +1 +1 +1 +25 +1
11. ATTENTION! This is still about microservices
12. 100. Player 1 88. Player 3 80. Player 5 75. Player 2 68. Player 6 30. Player 4 7. Player 7 Scoreboard +1 +1 +1 +100 +1 Real Enterprise
13. 100. Player 1 88. Player 3 80. Player 5 75. Player 2 68. Player 6 30. Player 4 7. Player 7 Scoreboard + + + +10 + Real Enterprise
14. 100. Player 1 88. Player 3 80. Player 5 75. Player 2 68. Player 6 30. Player 4 7. Player 7 Scoreboard + + + +10 + Real Enterprise ← Elastic Storage Ы
15. 100. Player 1 88. Player 3 80. Player 5 75. Player 2 68. Player 6 30. Player 4 7. Player 7 Scoreboard + + + +10 + Real Enterprise Ы
16. To Summarize • SERVER PUSH • PLAIN REQUEST-RESPONSE • CLIENT-SIDE STREAMING • SERVER-SIDE STREAMING
17. To Summarize • MACHINE LEARNING PIPE • WHERE SUBSCRIBER CAN WORK SLOW OR FAST • THIS SHOULD WORK STABLY
18. TOOLKIT
19. Back-end • SPRING FRAMEWORK 5 • PROJECT REACTOR 3 • PROTOCOL BUFFER (a.k.a PROTOBUF)
20. Front-end • PHASER 3 • REACTOR-JS • TYPESCRIPT • PROTOCOL BUFFER (a.k.a PROTOBUF)
21. OLD HTTP WAY
22. Why HTTP? • PLAIN AND SIMPLE • USED FOR MANY YEARS
23. @RestController @RequestMapping("/http") public class HttpGameController { ... @PostMapping("/start") public Mono<Config> start( @RequestBody Nickname nickname, @CookieValue("uuid") String uuid ) { return gameService.start(nickname) .subscriberContext(Context.of("uuid", UUID.fromString(uuid))); } } @RestController @RequestMapping("/http") public class HttpGameController { ... @PostMapping("/start") public Mono<Config> start( @RequestBody Nickname nickname, @CookieValue("uuid") String uuid ) { return gameService.start(nickname) .subscriberContext(Context.of("uuid", UUID.fromString(uuid))); } }
24. DEMO is.gd/webflux
25. • TEXT MESSAGE OVERHEAD • INEFFICIENT RESOURCE USAGE • SLOW PERFORMANCE • COMMUNICATION RIGIDITY • LACK OF PROPER FLOW CONTROL Why NOT HTTP?
26. HTTP FLOW CONTROL
27. HTTP FLOW CONTROL Retry logic Timeouts Circuit breaking Thundering herds Cascading failure Configuration
28. We need Backpressure
29. PROTOCOLS
30. PROTOCOLS • HTTP/1.x • TCP • HTTP/2 • ???
31. PROTOCOLS • HTTP/1.x • WEBSOCKET • HTTP/2 • ???
32. COMPARISON
33. • MAINTAINABILITY • Frameworks • Community/Adoption • STABILITY • Can work OK in unpredicted cases • PERFORMANCE
34. WEBSOCKET / HTTP2 WEBSOCKET
35. Why WebSocket? • NO OVERHEAD ~ TCP • HIGH-PERFORMANCE
36. Why NOT WebSocket? • COMPLEX DEVELOPMENT • REINVENT APPLICATION PROTOCOL
37. Existing Solutions • SOCKJS + STOMP • SOCKET.IO
38. SOCKET.IO
39. • MOST POPULAR IN JS WORLD • TOPIC BASED BINARY/TEXT MESSAGING • JAVA SERVER BUILT ON TOP OF NETTY Why Socket.IO?
40. DEMO is.gd/socketio
41. • NO INTEGRATION WITH SPRING • JS (CALLBACKS) CODE STYLE • NO ACCESS TO BYTEBUF final SocketIOServer server = new SocketIOServer(configuration); context.addApplicationListener(event -> { if (event instanceof ContextClosedEvent || event instanceof ContextStoppedEvent || event instanceof ApplicationFailedEvent) { server.stop(); } }); final SocketIOServer server = new SocketIOServer(configuration); context.addApplicationListener(event -> { if (event instanceof ContextClosedEvent || event instanceof ContextStoppedEvent || event instanceof ApplicationFailedEvent) { server.stop(); } }); final SocketIOServer server = new SocketIOServer(configuration); context.addApplicationListener(event -> { if (event instanceof ContextClosedEvent || event instanceof ContextStoppedEvent || event instanceof ApplicationFailedEvent) { server.stop(); } }); Why Not Socket.IO server.addConnectListener(client -> {}); server.addDisconnectListener(client -> {}); server.addEventListener("start", byte[].class, (client, data, ackSender) -> {}); server.addEventListener("locate", byte[].class, (client, data, ackRequest) -> {}); server.addEventListener("streamMetricsSnapshots", byte[].class, (client, data, ackSender) -> {}); server.addConnectListener(client -> {}); server.addDisconnectListener(client -> {}); server.addEventListener("start", byte[].class, (client, data, ackSender) -> {}); server.addEventListener("locate", byte[].class, (client, data, ackRequest) -> {}); server.addEventListener("streamMetricsSnapshots", byte[].class, (client, data, ackSender) -> {});
42. Where it is good • REALLY GOOD AT JS
43. GRPC WAY
44. Why gRPC? • BUILT ON TOP OF HTTP/2 • EASY TO BUILD API WITH PROTOBUF • GOOD DEVELOPMENT EXPERIENCE • SEAMLESS INTEGRATION WITH SPRING service GameService { rpc start (Nickname) returns (Config) {} } service PlayerService { rpc locate(stream Location) returns (google.protobuf.Empty) {} rpc players(google.protobuf.Empty) returns (stream Player) {} } service GameService { rpc start (Nickname) returns (Config) {} } service PlayerService { rpc locate(stream Location) returns (google.protobuf.Empty) {} rpc players(google.protobuf.Empty) returns (stream Player) {} } service GameService { rpc start (Nickname) returns (Config) {} } service PlayerService { rpc locate(stream Location) returns (google.protobuf.Empty) {} rpc players(google.protobuf.Empty) returns (stream Player) {} } service GameService { rpc start (Nickname) returns (Config) {} } service PlayerService { rpc locate(stream Location) returns (google.protobuf.Empty) {} rpc players(google.protobuf.Empty) returns (stream Player) {} } protobuf { protoc { artifact = 'com.google.protobuf:protoc' } plugins { grpc { artifact = "io.grpc:protoc-gen-grpc-java" } } generateProtoTasks { ofSourceSet('main')*.plugins { grpc {} } } } @GRpcService public class GrpcPlayerController extends ReactorPlayerServiceGrpc.PlayerServiceImplBase { @Override public Flux<Player> players(Mono<Empty> message) { return playerService .players() .onBackpressureBuffer() .subscriberContext(Context.of("uuid", CONTEXT_UUID_KEY.get())); } } @GRpcService public class GrpcPlayerController extends ReactorPlayerServiceGrpc.PlayerServiceImplBase { @Override public Flux<Player> players(Mono<Empty> message) { return playerService .players() .onBackpressureBuffer() .subscriberContext(Context.of("uuid", CONTEXT_UUID_KEY.get())); } }
45. DEMO is.gd/rgrpc
46. Why NOT GRPC?
49. GRPC-WEB CONNECTION 1 HTTP/2 HTTP/1.x CONNECTION 1 CONNECTION 2
50. GRPC-WEB HTTP/2 HTTP/1.x STATIC CONNECTION 1 STATIC CONNECTION 2
51. –gRPC “WE HAVE BACKPRESSURE CONTROL”
52. GRPC SUBSCRIBER new CallStreamObserver<>() { @Override public void onNext(Object value) { this.request(5); } } new CallStreamObserver<>() { @Override public void onNext(Object value) { this.request(5); } }
53. gRPC PUBLISHER if (observer.isReady()) { observer.onNext(message); } if (observer.isReady()) { observer.onNext(message); }
55. WHAT IF PUBLISHER THAT MAY OVERPRODUCE PUBLISHER PUBLISHER PUBLISHER PUBLISHER
56. Scenario Ы
57. Scenario Ы https://youtu.be/KxAjxUrGbcY
59. Publisher → Subscriber →
61. CloudNative JVM Setup • -Xms 256m • -Xmx 1g • -XX:MaxDirectMemorySize=1g
63. –gRPC “WE HAVE BACKPRESSURE CONTROL”
64. –PRODUCTION “YEAH… YOU HAVE… BUT… NOT REALLY”
65. Summary • Everything is either SLOW, HARD to implement or LACKS browser support • Flow control is far from needed • Do you want to waste your time in searching how to solve the problems???
67. STREAM STREAM STREAM
68. Netflix case study on gRPC • Reactive Streaming Service Networking with Ryland Degnan 
 (ex Netflix Edge Platform)
 
 https://bit.ly/2FUvHG3
69. RSOCKET WAY
70. What is RSocket?
71. What is RSocket?
72. REACTIVE-STREAMS as NETWORK PROTOCOL
73. is.gd/rsocket DEMO
74. 74 Binary
75. 75 Multiplexed
76. STREAM BLUE STREAM YELLOW STREAM RED 76 Multiplexed Project Reactor
77. 77 Transport Agnostic WebSocket HTTP/2 TCP QUIC Aeron
78. 78 Backpressure Reactive-Streams 10 9
79. 79 STREAM BLUE STREAM RED Client can implement request handler Peer-to-peer CLIENT SERVER CLIENT
80. 80 Interaction modes Multi
81. 81 Request-Response Interaction modes STREAM YELLOW
82. 82 Fire-and-Forget Interaction modes STREAM YELLOW
83. 83 Request-Stream Interaction modes STREAM YELLOW
84. 84 Stream-Stream Interaction modes STREAM YELLOW
85. 85 Notable Features • LEASING - GIVE CAPACITY TO CLIENTS, AVOID CIRCUIT BREAKERS • RESUMABILITY - RESUME STREAMS IF CONNECTION LOST • FRAGMENTATION - SPLIT LARGE PAYLOAD ONTO SMALLER CHUNKS
87. SOME CODE
88. RPC API
89. RPC API implementation 'io.rsocket.rpc:rsocket-rpc-core'
90. RPC API protobuf { generatedFilesBaseDir = "${projectDir}/src/generated" protoc { artifact = 'com.google.protobuf:protoc' } plugins { rsocketRpc { artifact = "io.rsocket.rpc:rsocket-rpc-protobuf" } } generateProtoTasks { ofSourceSet('main')*.plugins { rsocketRpc {} } } } protobuf { generatedFilesBaseDir = "${projectDir}/src/generated" protoc { artifact = 'com.google.protobuf:protoc' } plugins { rsocketRpc { artifact = "io.rsocket.rpc:rsocket-rpc-protobuf" } } generateProtoTasks { ofSourceSet('main')*.plugins { rsocketRpc {} } } }
91. RPC API
92. RSocketRpcService public class ExtrasController implements org.coinen.pacman.ExtrasService { … @Override public Flux<Extra> extras(Empty message, ByteBuf metadata) { return extrasService.extras(); } } public class ExtrasController implements org.coinen.pacman.ExtrasService { … @Override public Flux<Extra> extras(Empty message, ByteBuf metadata) { return extrasService.extras(); } } public class ExtrasController implements org.coinen.pacman.ExtrasService { … @Override public Flux<Extra> extras(Empty message, ByteBuf metadata) { return extrasService.extras(); } }
93. SPRING-MESSAGING implementation 'org.springframework.boot:spring-boot-starter-rsocket'
94. SPRING-MESSAGING server.port=3000 spring.rsocket.server.transport=websocket
95. SPRING-MESSAGING @Controller @MessageMapping(“my.route.name”) public class ExtrasController { … @MessageMapping(“handle.extras”) public Flux<Extra> extras() { return extrasService.extras(); } } @Controller @MessageMapping(“my.route.name”) public class ExtrasController { … @MessageMapping(“handle.extras”) public Flux<Extra> extras() { return extrasService.extras(); } } @Controller @MessageMapping(“my.route.name”) public class ExtrasController { … @MessageMapping(“handle.extras”) public Flux<Extra> extras() { return extrasService.extras(); } }
97. STRESS TEST
98. Scenario 10 3 3 3 3 10 3 3 3 3 10 3 3 3 3 4 1 1 1 1 4 1 1 1 1 Ы
101. Advantages • SIMPLICITY IN DEVELOPMENT • EFFICIENT RESOURCE USAGE • HIGH PERFORMANCE • HIGH FLEXIBILITY • EFFECTIVE RELIABILITY
102. Disadvantages • STILL UNDER DEVELOPMENT • NARROW ADOPTION (FOR NOW)
103. 103 Maintainers
104. Summary PERFORMANCE RELIABILITY ADOPTION / COMUNITY 
 DEVELOPERS EXP HTTP 1.X WEBSOCKET GRPC(HTTP/2) / RSOCKET
105. Summary • EACH PROTOCOL HAS IT`S BENEFITS • SOCKET.IO IS THE BEST IN JS WORLD • gRPC PERFORMS REALLY WELL FOR SERVER • BUT REACTIVE IS ABOUT RESILIENCY • WHERE RSOCKET FULLY COVERS OUR USE-CASE
106. Resources • COMMUNITY -> https://community.netifi.com • VIDEO CHANNEL -> https://bit.ly/2Fku9VC • RSOCKET IN SPRING -> https://bit.ly/2OiUmrD • CLOUD NATIVE RSOCKET -> https://bit.ly/2JvDFdJ @OlehDokuka @netifi_inc
107. Q&A @OlehDokuka @netifi_inc PRESENTATION SOURCE CODE