This document summarizes a presentation comparing gRPC and REST by Alex Borysov and Mykyta Protsenko. It begins with introductions of the presenters and their backgrounds. It then discusses key differences between gRPC and REST such as gRPC using protocol buffers for defining APIs and being non-blocking via streaming, while REST focuses on resources and uses JSON/HTTP. Examples are provided of implementing services and clients for both approaches. Challenges of microservices and distributed systems that both aim to address are also covered.

1. gRPC vs REST: let the battle begin!
JavaDay, November 4, 2017
Alex Borysov, Software Engineer @ Google
Mykyta Protsenko, Software Engineer @ Roku

2. Who are we?
Mykyta Protsenko
Software Engineer @ Roku
• passionate about all things scalable
• 18+ years in software engineering
• Author of Henka
REST vs gRPC
Alex Borysov
Software Engineer @ Google
• large scale systems developer
• 11+ years in software engineering
• Active gRPC user
REST vs gRPC
@aiborisov
@mykyta_p

3. @aiborisov
@mykyta_p
@aiborisov
@mykyta_p

4. JSON over HTTP
@aiborisov
@mykyta_p

5. I am getting frustrated by the number of people calling any
HTTP-based interface a REST API.
Roy Fielding
http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven
@aiborisov
@mykyta_p

6. @aiborisov
@mykyta_p

7. @aiborisov
@mykyta_p

8. RESTful API
GET /user/15
{
“name”: “John Doe”,
“email”:“john.doe@gmail.com”,
...
}
non-RESTful API
GET /last_search?page=2
{
“products”: [...]
...
}
@aiborisov
@mykyta_p

9. What is gRPC?
gRPC stands for gRPC Remote Procedure Calls.
A high performance, general purpose, feature-rich
RPC framework.
Part of Cloud Native Computing Foundation cncf.io
HTTP/2 and mobile first.
Open sourced version of Stubby RPC used in Google.
@aiborisov
@mykyta_p

10. RPC?! But...
AMF?
RMI?
CORBA?
@aiborisov
@mykyta_p

11. gRPC is not RMI
Maitainability
Ease of use
Performance
Scalability
L
e
s
s
o
n
s
Years of using Stubby
@aiborisov
@mykyta_p

12. What is gRPC?
Abstractions and best practices on how to design
RPCs.
Default implementation(s) from Google.
Extension points to plug custom implementations and
modifications.
Supports 10+ programming languages.
@aiborisov
@mykyta_p

13. gRPC Interoperability
Java
Service
Python
Service
GoLang
Service
C++
Service
gRPC
Service
gRPC
Stub
gRPC
Stub
gRPC
Stub
gRPC
Stub
gRPC
Service
gRPC
Service
gRPC
Service
gRPC
Stub
@aiborisov
@mykyta_p

14. Apples to Oranges?
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@mykyta_p

15. Microservices?
@aiborisov
@mykyta_p

16. Microservices?
How to draw an owl?
@aiborisov
@mykyta_p

17. Microservices?
How to draw an owl?
How to build microservices?
@aiborisov
@mykyta_p

18. Microservices?
How to draw an owl?
How to build microservices?
Draw some circles.
@aiborisov
@mykyta_p

19. Microservices?
How to draw an owl?
How to build microservices?
Draw some circles.
Take XYZ framework.
@aiborisov
@mykyta_p

20. Microservices?
How to draw an owl?
How to build microservices?
Draw the REST of the owlDraw some circles.
Take XYZ framework.
@aiborisov
@mykyta_p

21. Microservices?
How to draw an owl?
How to build microservices?
Draw the REST of the owl
Write your microservices!
Draw some circles.
Take XYZ framework.
@aiborisov
@mykyta_p

22. Microservices
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@mykyta_p

23. Microservices
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@mykyta_p

24. Microservices
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@mykyta_p

25. Microservices
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@mykyta_p

26. Remote Calls
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27. Call Flow
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@mykyta_p

28. Service Discovery?
?
?
?
?
?
?
@aiborisov
@mykyta_p

29. Multiple Instances
#1
#N
#2
. . .
@aiborisov
@mykyta_p

30. Multiple Instances
#1
#N
#2
?
?
?
. . .
@aiborisov
@mykyta_p

31. Call Flow
@aiborisov
@mykyta_p

32. Call Flow
@aiborisov
@mykyta_p

33. Call Flow
@aiborisov
@mykyta_p

34. Call Flow
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@mykyta_p

35. Call Flow
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@mykyta_p

36. Slow Services?
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@mykyta_p

37. Failure Scenarios
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@mykyta_p

38. A distributed system is one in which the failure of a
computer you didn't even know existed can render your own
computer unusable.
Leslie Lamport, 1987
https://www.microsoft.com/en-us/research/wp-content/uploads/2016/12/Distribution.pdf
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@mykyta_p

39. Fault Tolerance
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@mykyta_p

40. Microservices?! But...
Performance Hit?
Service Discovery?
Load Balancing?
Fault Tolerance?
Monitoring?
Testing?
@aiborisov
@mykyta_p

41. Microservices?! But...
Performance Hit?
Service Discovery?
Load Balancing?
Fault Tolerance?
Monitoring?
Testing?
@aiborisov
@mykyta_p

42. Sample Problem
Client
@aiborisov
@mykyta_p

43. Sample Problem: Aggregator
Src
#2
Src
#1
Aggr
...
Src
#X
Client
@aiborisov
@mykyta_p

44. Heterogeneous Data Format
Src
#2
Src
#1
Aggr
...
Src
#X
<XML>...<XML>
{JSON}
Binary 110011
[ Unified Format ]
Client
@aiborisov
@mykyta_p

45. REST: It’s All About Resources
@aiborisov
@mykyta_p

46. REST: Call Hierarchy
Controller
Service
Data Source A
. . .
Data Source N
RestTemplate
RestTemplate
RestTemplate
@aiborisov
@mykyta_p

47. REST: Data Source
JSON
URL: http://zrada.com/content/11
{
"id": 11,
"content": "EJB 2.1",
"next_uri": "/content/12"
}
XML
URL: http://peremoga.com/content/22
<ContentResponse>
<id>22</id>
<content>JavaDay is live!</content>
</ContentResponse>
@aiborisov
@mykyta_p

48. REST: Data Source
...
ResponseEntity<Content> contentEntity = restTemplate.getForEntity(
url + "{content_id}"
Content.class,
ImmutableMap.of("content_id", contentId));
...
@aiborisov
@mykyta_p

49. REST: Service
public class AggregatingService {
public AggregatedContent fetch(int id) {
...
return new AggregatedContent(...);
}
}
public class AggregatedContent {
private final Integer id; // 115
private final String type; // ZRADA
private final String content; // Политики украли у детей...
private final Integer nextId; // 116
@aiborisov
@mykyta_p

50. REST: Service
public class AggregatingService {
public AggregatedContent fetch(int id) {
...
return new AggregatedContent(...);
}
}
public class AggregatedContent {
private Integer id;
private String type;
private String content;
private Integer nextId;
@aiborisov
@mykyta_p

51. REST: Service
public class AggregatingService {
public AggregatedContent fetch(int id) {
...
return new AggregatedContent(...);
}
}
public class AggregatedContent {
private Integer id; // 115
private String type; // ZRADA
private String content; // EJB 2.1
private Integer nextId; // 116
@aiborisov
@mykyta_p

52. REST: Service
public class AggregatingService {
public AggregatedContent fetch(int id) {
...
return new AggregatedContent(...);
}
}
public class AggregatedContent {
private Integer id; // 115
private String type; // ZRADA
private String content; // EJB 2.1
private Integer nextId; // 116
@aiborisov
@mykyta_p

53. REST: Controller
@GetMapping(
value = "/content/{id}",
produces = "application/json")
public AggregatedContent aggregated(@PathVariable("id") int id) {
return aggregatingService.fetch(id);
}
@aiborisov
@mykyta_p

54. REST: It’s All About Resources
@GetMapping(
value = "/content/{id}",
produces = "application/json")
public AggregatedContent aggregated(@PathVariable("id") int id) {
return aggregatingService.fetch(id);
}
@aiborisov
@mykyta_p

55. REST: It’s simple
http://localhost:8080/content/115
{
"id": 115,
"content_type": "PEREMOGA",
"content": "JavaDay 2017 is live",
"next_uri": "/content/116"
}
@aiborisov
@mykyta_p

56. REST: Service Discovery
@aiborisov
@mykyta_p

57. k8s/zrada.yaml
...
kind: Service
metadata:
name: rest-zrada-content-service
k8s/aggregator.yaml
...
env:
- name: datasource_a_url
value: "http://rest-zrada-content-service:8080"
REST: Service Discovery
@aiborisov
@mykyta_p

58. k8s/zrada.yaml
...
kind: Service
metadata:
name: rest-zrada-content-service
k8s/aggregator.yaml
...
env:
- name: datasource_a_url
value: "http://rest-zrada-content-service:8080"
REST: Service Discovery
@aiborisov
@mykyta_p

59. Controllers and POJOs, oh my!
public class AggregatedContent {
@JsonProperty("id")
private Integer id;
@JsonProperty("type")
private String type;
@JsonProperty("content")
private String content;
@JsonProperty("next_uri")
private String nextUri;
...
}
{
"id": 115,
"content_type": "ZRADA",
"content": "EJB 2.1",
"next_uri": "/content/116"
}
@aiborisov
@mykyta_p

60. gRPC: It’s All About APIs
@aiborisov
@mykyta_p

61. Sample Problem: Aggregator
Src
#2
Src
#1
Aggr
...
Src
#X
Client
@aiborisov
@mykyta_p

62. Service Definition (aggregator.proto)
@aiborisov
@mykyta_p

63. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Get(AggregationRequest)
returns (AggregationResponse);
}
@aiborisov
@mykyta_p

64. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Get(AggregationRequest)
returns (AggregationResponse);
}
message AggregationRequest {
int32 item_id = 1;
}
message AggregationResponse {
int32 id = 1;
ResponseType type = 2;
string content = 3;
int32 next_item_id = 4;
}
enum ResponseType {
UNDEFINED = 0;
PEREMOGA = 1;
ZRADA = 2;
}
@aiborisov
@mykyta_p

65. Service Definition
aggregator.proto
@aiborisov
@mykyta_p

66. Service Definition
aggregator.proto
gRPC Runtime
@aiborisov
@mykyta_p

67. Service Definition
aggregator.proto
AggregationServiceImplBase.java AggregationRequest.java
AggregationResponse.java
AggregationServiceStub.java
AggregationServiceFutureStub.java
AggregationServiceBlockingStub.java
Service Implementation Request and response Client libraries
gRPC Java runtime
@aiborisov
@mykyta_p

68. Implement gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void get(AggregationRequest request,
StreamObserver<AggregationResponse> responseObserver) {
}
}
@aiborisov
@mykyta_p

69. Implement gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void get(AggregationRequest request,
StreamObserver<AggregationResponse> responseObserver) {
}
}

70. Implement gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void get(AggregationRequest request,
StreamObserver<AggregationResponse> responseObserver) {
}
}
@aiborisov
@mykyta_p

71. Thread #X
Thread ...
Thread #7
Thread #6
Thread #5
Thread #4
Blocking API (aka Thread-per-Request)?
Thread #3
Thread #2
Thread #1
Thread pool
of size X
@aiborisov
@mykyta_p

72. Thread #X
Thread ...
Thread #7
Thread #6
Thread #5
Thread #4
Blocking API (aka Thread-per-Request)?
Thread #3
Thread #2
Thread #1
Thread pool
of size X
1
@aiborisov
@mykyta_p

73. Thread #X
Thread ...
Thread #7
Thread #6
Thread #5
Thread #4
Blocking API (aka Thread-per-Request)?
Thread #3
Thread #2
Thread #1
Thread pool
of size X
1
2
@aiborisov
@mykyta_p

74. Thread #X
Thread ...
Thread #7
Thread #6
Thread #5
Thread #4
Blocking API (aka Thread-per-Request)?
Thread #3
Thread #2
Thread #1
Thread pool
of size X
1
2
3
@aiborisov
@mykyta_p

75. Thread #X
Thread ...
Thread #7
Thread #6
Thread #5
Thread #4
Thread #3
Thread #2
Blocking API (aka Thread-per-Request)?
Thread #1
Thread pool
of size X
1
2
3
X
. . .
@aiborisov
@mykyta_p

76. Thread #X
Thread ...
Thread #7
Thread #6
Thread #5
Thread #4
Thread #3
Thread #2
Blocking API (aka Thread-per-Request)?
Thread #1
Thread pool
of size X
1
2
3
X
. . .
X + 1
@aiborisov
@mykyta_p

77. Thread #X
Thread ...
Thread #7
Thread #6
Thread #5
Thread #4
Thread #3
Thread #2
Blocking API (aka Thread-per-Request)?
Thread #1
Thread pool
of size X
1
2
3
X
. . .
X + 1
@aiborisov
@mykyta_p

78. Implement gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void get(AggregationRequest request,
StreamObserver<AggregationResponse> responseObserver) {
}
}
@aiborisov
@mykyta_p

79. Implement gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void get(AggregationRequest request,
public interface StreamObserver<AggregationResponse> responseObserver){{
void onNext(AggregationResponse response);
void onCompleted();
void onError(Throwable error);
}
}
}
@aiborisov
@mykyta_p

80. Non-Blocking API
1
2
3
. . .
X + Y
X
. . .
@aiborisov
@mykyta_p

81. Non-Blocking API (aka Hollywood Principle)
1
2
3
. . .
X + Y
X
. . .
WillCallYouLater!
@aiborisov
@mykyta_p

82. Non-Blocking API (aka Hollywood Principle)
1
2
3
. . .
X + Y
X
. . .
WillCallYouLater!
onNext(1)
@aiborisov
@mykyta_p

83. Non-Blocking API (aka Hollywood Principle)
1
2
3
. . .
X + Y
X
. . .
WillCallYouLater!
onNext(3)
@aiborisov
@mykyta_p

84. Non-Blocking API (aka Hollywood Principle)
1
2
3
. . .
X + Y
X
. . .
WillCallYouLater!
onNext(X)
@aiborisov
@mykyta_p

85. Implement gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void get(AggregationRequest request,
StreamObserver<AggregationResponse> responseObserver) {
AggregationResponse response = AggregationResponse
.newBuilder()
.setId(request.getItemId())
.setContent("JavaDay 2017 is happening right now!")
.setType(ResponseType.PEREMOGA)
.build();
responseObserver.onNext(response);
responseObserver.onCompleted();
}
}
@aiborisov
@mykyta_p

86. Implement gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void get(AggregationRequest request,
StreamObserver<AggregationResponse> responseObserver) {
AggregationResponse response = AggregationResponse
.newBuilder()
.setId(request.getItemId())
.setContent("JavaDay 2017 is happening right now!")
.setType(ResponseType.PEREMOGA)
.build();
responseObserver.onNext(response);
responseObserver.onCompleted();
}
}
@aiborisov
@mykyta_p

87. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Get(AggregationRequest)
returns (AggregationResponse);
}
message AggregationRequest {
int32 item_id = 1;
}
message AggregationResponse {
int32 id = 1;
ResponseType type = 2;
string content = 3;
int32 next_item_id = 4;
}
enum ResponseType {
UNDEFINED = 0;
PEREMOGA = 1;
ZRADA = 2;
}
@aiborisov
@mykyta_p

88. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Get(AggregationRequest)
returns (AggregationResponse);
}
message AggregationRequest {
}
message AggregationResponse {
int32 id = 1;
ResponseType type = 2;
string content = 3;
}
enum ResponseType {
UNDEFINED = 0;
PEREMOGA = 1;
ZRADA = 2;
}
@aiborisov
@mykyta_p

89. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Get(AggregationRequest)
returns (AggregationResponse);
}
message AggregationRequest {
}
message AggregationResponse {
int32 id = 1;
ResponseType type = 2;
string content = 3;
}
enum ResponseType {
UNDEFINED = 0;
PEREMOGA = 1;
ZRADA = 2;
}
@aiborisov
@mykyta_p

90. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Get(AggregationRequest)
returns (stream AggregationResponse);
}
message AggregationRequest {
}
message AggregationResponse {
int32 id = 1;
ResponseType type = 2;
string content = 3;
}
enum ResponseType {
UNDEFINED = 0;
PEREMOGA = 1;
ZRADA = 2;
}
@aiborisov
@mykyta_p

91. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Subscribe(AggregationRequest)
returns (stream AggregationResponse);
}
message AggregationRequest {
}
message AggregationResponse {
int32 id = 1;
ResponseType type = 2;
string content = 3;
}
enum ResponseType {
UNDEFINED = 0;
PEREMOGA = 1;
ZRADA = 2;
}
@aiborisov
@mykyta_p

92. Service Definition (aggregator.proto)
syntax = "proto3";
service AggregationService {
rpc Subscribe(AggregationRequest)
returns (stream AggregationResponse);
}
message AggregationRequest {
}
message AggregationResponse {
int32 id = 1;
ResponseType type = 2;
string content = 3;
}
enum ResponseType {
UNDEFINED = 0;
PEREMOGA = 1;
ZRADA = 2;
}
@aiborisov
@mykyta_p

93. Sample Problem: Aggregator
Src
#2
Src
#1
Aggr
...
Src
#X
Client
aggregator.proto
@aiborisov
@mykyta_p

94. Sample Problem: Content
Src
#2
Src
#1
Aggr
...
Src
#X
Client
aggregator.proto
content.proto
@aiborisov
@mykyta_p

95. content.proto
syntax = "proto3";
service ContentService {
rpc Subscribe(ContentRequest)
returns (stream ContentResponse);
}
message ContentRequest {
}
message ContentResponse {
int32 id = 1;
string content = 2;
}
@aiborisov
@mykyta_p

96. Streaming gRPC Service
public class AggregationService extends AggregationServiceImplBase {
private final Collection<ContentServiceStub> contentStubs;
public AggregationService(Collection<ContentServiceStub> contentStubs) {
this.contentStubs = contentStubs;
}
...
@aiborisov
@mykyta_p

97. Streaming gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void subscribe(AggregationRequest request,StreamObserver<AggregationResponse> responseObserver) {
contentStubs.forEach(stub -> { stub.subscribe(ContentRequest.getDefaultInstance(),
new StreamObserver<ContentResponse>() {
@Override
public void onNext(ContentResponse response) {
...
}
@Override
public void onError(Throwable error) {
responseObserver.onError(error);
}
@Override
public void onCompleted() {}
});
});
}
@aiborisov
@mykyta_p

98. Streaming gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void subscribe(AggregationRequest request,StreamObserver<AggregationResponse> responseObserver) {
contentStubs.forEach(stub -> { stub.subscribe(ContentRequest.getDefaultInstance(),
new StreamObserver<ContentResponse>() {
@Override
public void onNext(ContentResponse response) {
...
}
@Override
public void onError(Throwable error) {
responseObserver.onError(error);
}
@Override
public void onCompleted() {}
});
});
}
@aiborisov
@mykyta_p

99. Streaming gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void subscribe(AggregationRequest request,StreamObserver<AggregationResponse> responseObserver) {
contentStubs.forEach(stub -> { stub.subscribe(ContentRequest.getDefaultInstance(),
new StreamObserver<ContentResponse>() {
@Override
public void onNext(ContentResponse response) {
...
}
@Override
public void onError(Throwable error) {
responseObserver.onError(error);
}
@Override
public void onCompleted() {}
});
});
}
@aiborisov
@mykyta_p

100. Streaming gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void subscribe(AggregationRequest request,StreamObserver<AggregationResponse> responseObserver) {
contentStubs.forEach(stub -> { stub.subscribe(ContentRequest.getDefaultInstance(),
new StreamObserver<ContentResponse>() {
@Override
public void onNext(ContentResponse response) {
...
}
@Override
public void onError(Throwable error) {
responseObserver.onError(error);
}
@Override
public void onCompleted() {}
});
});
}
@aiborisov
@mykyta_p

101. Streaming gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void subscribe(AggregationRequest request,StreamObserver<AggregationResponse> responseObserver) {
contentStubs.forEach(stub -> { stub.subscribe(ContentRequest.getDefaultInstance(),
new StreamObserver<ContentResponse>() {
@Override
public void onNext(ContentResponse response) {
ResponseType type = typeForStub(stub);
int aggregationId = aggregationId(response.getId(), type);
AggregationResponse aggrResponse =
AggregationResponse.newBuilder()
.setContent(response.getContent()).setId(aggregationId).
.setType(type).build();
responseObserver.onNext(aggrResponse);
}
});
});
}
@aiborisov
@mykyta_p

102. Streaming gRPC Service
public class AggregationService extends AggregationServiceImplBase {
@Override
public void subscribe(AggregationRequest request,StreamObserver<AggregationResponse> responseObserver) {
contentStubs.forEach(stub -> { stub.subscribe(ContentRequest.getDefaultInstance(),
new StreamObserver<ContentResponse>() {
@Override
public void onNext(ContentResponse response) {
ResponseType type = typeForStub(stub);
int aggregationId = aggregationId(response.getId(), type);
AggregationResponse aggrResponse =
AggregationResponse.newBuilder()
.setContent(response.getContent()).setId(aggregationId).
.setType(type).build();
responseObserver.onNext(aggrResponse);
}
});
});
}
@aiborisov
@mykyta_p

103. Streaming gRPC Service
Src
#2
Src
#1
Aggr
...
Src
#X
Client
@aiborisov
@mykyta_p

104. Streaming gRPC Service
Src
#2
Src
#1
Aggr
...
Src
#X
Client Subscribe()
@aiborisov
@mykyta_p

105. Streaming gRPC Service
Src
#2
Src
#1
Aggr
...
Src
#X
Client Subscribe()
Subscribe()
Subscribe()
Subscribe()
@aiborisov
@mykyta_p

106. Streaming gRPC Service
Src
#2
Src
#1
Aggr
...
Src
#X
Client
onNext()
@aiborisov
@mykyta_p

107. Streaming gRPC Service
Src
#2
Src
#1
Aggr
...
Src
#X
Client
onNext()
onNext()
@aiborisov
@mykyta_p

108. Streaming gRPC Service
Src
#2
Src
#1
Aggr
...
Src
#X
Client
onNext()
@aiborisov
@mykyta_p

109. Streaming gRPC Service
Src
#2
Src
#1
Aggr
...
Src
#X
Client onNext()
onNext()
@aiborisov
@mykyta_p

110. Start gRPC Server
ContentServiceStub peremogaClient = ...
ContentServiceStub zradaClient = ...
Server grpcServer = NettyServerBuilder.forPort(8080)
.addService(new AggregationService(asList(peremogaClient, zradaClient)))
.build().start();
@aiborisov
@mykyta_p

111. Start gRPC Server
ContentServiceStub peremogaClient = ...
ContentServiceStub zradaClient = ...
Server grpcServer = NettyServerBuilder.forPort(8080)
.addService(new AggregationService(asList(peremogaClient, zradaClient)))
.build().start();
@aiborisov
@mykyta_p

112. Create gRPC Client
String host = System.getenv("peremoga_host");
int post = Integer.valueOf(System.getenv("peremoga_port"));
ManagedChannel peremogaChannel = NettyChannelBuilder.forAddress(host, port).build();
@aiborisov
@mykyta_p

113. Create gRPC Client
String host = System.getenv("peremoga_host");
int post = Integer.valueOf(System.getenv("peremoga_port"));
ManagedChannel peremogaChannel = NettyChannelBuilder.forAddress(host, port).build();
ContentServiceStub peremogaClient = ContentServiceGrpc.newStub(peremogaChannel);
@aiborisov
@mykyta_p

114. Create gRPC Client
String host = System.getenv("peremoga_host");
int port = Integer.valueOf(System.getenv("peremoga_port"));
ManagedChannel peremogaChannel = NettyChannelBuilder.forAddress(host, port).build();
ContentServiceStub peremogaClient = ContentServiceGrpc.newStub(peremogaChannel);
ContentServiceBlockingStub peremogaBlockingClient =
ContentServiceGrpc.newBlockingStub(peremogaChannel);
ContentServiceFutureStub peremogaFutureClient =
ContentServiceGrpc.newFutureStub(peremogaChannel);
@aiborisov
@mykyta_p

115. Service Discovery & Load Balancing
String host = System.getenv("peremoga_host");
int post = Integer.valueOf(System.getenv("peremoga_port"));
ManagedChannel peremogaChannel = NettyChannelBuilder.forAddress(host, port).build();
@aiborisov
@mykyta_p

116. Service Discovery & Load Balancing
ManagedChannel peremogaChannel = NettyChannelBuilder.forAddress(host, port).build();
@aiborisov
@mykyta_p

117. Service Discovery & Load Balancing
ManagedChannel peremogaChannel = NettyChannelBuilder.forTarget("peremoga")
.build();
@aiborisov
@mykyta_p

118. Service Discovery & Load Balancing
ManagedChannel peremogaChannel = NettyChannelBuilder.forTarget("peremoga")
.nameResolverFactory(new DnsNameResolverProvider())
.loadBalancerFactory(RoundRobinLoadBalancerFactory.getInstance())
.build();
@aiborisov
@mykyta_p

119. Service Discovery & Load Balancing
ManagedChannel peremogaChannel = NettyChannelBuilder.forTarget("peremoga")
.nameResolverFactory(new MyCustomNameResolverProviderFactory())
.loadBalancerFactory(new MyMoonPhaseLoadBalancerFactory())
.build();
@aiborisov
@mykyta_p

120. Netty
ManagedChannel peremogaChannel = NettyChannelBuilder.forTarget("peremoga")
.nameResolverFactory(new MyCustomNameResolverProvider())
.loadBalancerFactory(new MyMoonPhaseLoadBalancerFactory())
.build();
@aiborisov
@mykyta_p

121. Netty + HTTP/2 + Protobuf
@aiborisov
@mykyta_p

122. Netty + HTTP/2 + Protobuf = Performance
http://www.grpc.io/docs/guides/benchmarking.html
@aiborisov
@mykyta_p
8 core VMs, streaming throughput

123. Netty + HTTP/2 + Protobuf = Performance
http://www.grpc.io/docs/guides/benchmarking.html
@aiborisov
@mykyta_p
32 core VMs, streaming throughput

124. Client Latency
...
900 ms!
@aiborisov
@mykyta_p

125. Caching
CDN
9 ms
...
@aiborisov
@mykyta_p

126. pay 24/7
Classic Cloud
VM
VM
LB
...
VM
pay as you go
@aiborisov
@mykyta_p

127. Serverless
pay as you go
Func
Funcinput
...
Func
input
...
input
@aiborisov
@mykyta_p

128. All about resources
IDL optional
Synchronous by default
Unary
Perfect fit for serverless
All about APIs
IDL centric
Asynchronous by nature
Streaming or Unary
Performance first
REST gRPC
@aiborisov
@mykyta_p

129. Sample Problem
Src
#2
Src
#1
...
Src
#X
Client Aggr
@aiborisov
@mykyta_p

130. Sample Problem: Voting
Src
#2
Src
#1
...
Src
#X
Client
Voting
Aggr
@aiborisov
@mykyta_p

131. Sample Problem: Voting
Src
#2
Src
#1
...
Src
#X
Client
Voting
Aggr
@aiborisov
@mykyta_p

132. Sample Problem: Voting
Src
#2
Src
#1
...
Src
#X
Client
Voting
Aggr
@aiborisov
@mykyta_p

133. Sample Problem: Voting & Leaderboard
Src
#2
Src
#1
...
Src
#X
Client
Voting
Aggr
L-board
@aiborisov
@mykyta_p

134. Sample Problem: Voting & Leaderboard
Src
#2
Src
#1
...
Src
#X
Client
Voting
Aggr
L-board
@aiborisov
@mykyta_p

135. Sample Problem: Voting & Leaderboard
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
Aggr
L-board
@aiborisov
@mykyta_p

136. Sample Problem
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

137. Failing Leaderboard
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
Aggr
@aiborisov
@mykyta_p

138. Cascading Failure
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
Aggr
@aiborisov
@mykyta_p

139. Cascading Failure
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
Aggr
@aiborisov
@mykyta_p

140. Cascading Failure
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
Aggr
@aiborisov
@mykyta_p

141. Circuit Breaker
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

142. Circuit Breaker
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

143. Circuit Breaker
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

144. Circuit Breaker
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

145. Circuit Breaker
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

146. Circuit Breaker
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

147. Slow Services
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

148. Timeouts?
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
200 ms
2 sec
@aiborisov
@mykyta_p

149. Large Timeouts
Gateway Voting L-Board
1,000 ms
timeout
1,000 ms
timeout
200 ms
client timeout
@aiborisov
@mykyta_p

150. Large Timeouts
Gateway Voting L-Board
1,000 ms
timeout
1,000 ms
timeout
200 ms
client timeout
50 ms
@aiborisov
@mykyta_p

151. Large Timeouts
Gateway Voting L-Board
1,000 ms
timeout
1,000 ms
timeout
200 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

152. Large Timeouts
Gateway Voting L-Board
1,000 ms
timeout
1,000 ms
timeout
200 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

153. Large Timeouts
Gateway Voting L-Board
1,000 ms
timeout
1,000 ms
timeout
200 ms
client timeout
50 ms
400 ms
300 ms
@aiborisov
@mykyta_p

154. Short Timeouts
Gateway Voting L-Board
100 ms
timeout
100 ms
timeout
@aiborisov
@mykyta_p

155. Short Timeouts
Gateway Voting L-Board
100 ms
timeout
100 ms
timeout
2,000 ms
client timeout
@aiborisov
@mykyta_p

156. Short Timeouts
Gateway Voting L-Board
100 ms
timeout
100 ms
timeout
2,000 ms
client timeout
50 ms
@aiborisov
@mykyta_p

157. Short Timeouts
Gateway Voting L-Board
100 ms
timeout
100 ms
timeout
2,000 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

158. Short Timeouts
Gateway Voting L-Board
100 ms
timeout
100 ms
timeout
2,000 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

159. Short Timeouts
Gateway Voting L-Board
100 ms
timeout
100 ms
timeout
2,000 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

160. gRPC Deadline Propagation
Gateway Voting L-Board
200 ms
client timeout
@aiborisov
@mykyta_p

161. gRPC Deadline Propagation
Gateway Voting L-Board
200 ms
client timeout
50 ms
@aiborisov
@mykyta_p

162. gRPC Deadline Propagation
Gateway Voting L-Board
200 - 50 ms
timeout
200 ms
client timeout
50 ms
@aiborisov
@mykyta_p

163. gRPC Deadline Propagation
Gateway Voting L-Board
200 - 50 ms
timeout
200 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

164. gRPC Deadline Propagation
Gateway Voting L-Board
200 - 50 - 400 ms
timeout
200 - 50 ms
timeout
200 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

165. gRPC Deadline Propagation (Short)
Gateway Voting L-Board
200 - 50 - 400 ms
timeout
200 - 50 ms
timeout
200 ms
client timeout
50 ms
400 ms
@aiborisov
@mykyta_p

166. gRPC Deadline Propagation (Large)
Gateway Voting L-Board
2,000 - 50 - 400 ms
timeout
2,000 - 50 ms
timeout
2,000 ms
client timeout
50 ms
400 ms
300 ms
@aiborisov
@mykyta_p

167. Investigation
Src
#2
Src
#1
...
Src
#X
Gateway
VotingL-board
Aggr
@aiborisov
@mykyta_p

168. Gateway
VotingL-board
Aggr
Investigation
Src
#2
Src
#1
...
Src
#X
@aiborisov
@mykyta_p

169. VotingL-board
Aggr
Investigation
Src
#2
Src
#1
...
Src
#X
Gateway
@aiborisov
@mykyta_p

170. L-board
Aggr
Investigation
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
@aiborisov
@mykyta_p

171. L-board
Aggr
Investigation
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
@aiborisov
@mykyta_p

172. Aggr
L-board
Investigation
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
@aiborisov
@mykyta_p

173. Aggr
L-board
Investigation
Src
#2
Src
#1
...
Src
#X
Gateway
Voting
@aiborisov
@mykyta_p

174. Zipkin: Traces and Latency
@aiborisov
@mykyta_p

175. Zipkin and gRPC
https://github.com/openzipkin/brave/tree/master/instrumentation/grpc
URLConnectionSender sender = ...
GrpcTracing grpcTracing = GrpcTracing.create(Tracing.newBuilder()
.sampler(ALWAYS_SAMPLE).spanReporter(AsyncReporter.create(sender)).build());
@aiborisov
@mykyta_p

176. Zipkin and gRPC
https://github.com/openzipkin/brave/tree/master/instrumentation/grpc
URLConnectionSender sender = ...
GrpcTracing grpcTracing = GrpcTracing.create(Tracing.newBuilder()
.sampler(ALWAYS_SAMPLE).spanReporter(AsyncReporter.create(sender)).build());
ManagedChannel peremogaChannel = NettyChannelBuilder.forAddress(peremogaHost, peremogaPort)
.intercept(grpcTracing.newClientInterceptor())
.build();
Server grpcServer = NettyServerBuilder.forPort(8080)
.addService(new AggregationService(asList(peremogaClient, zradaClient)))
.intercept(grpcTracing.newServerInterceptor())
.build().start();
@aiborisov
@mykyta_p

177. Zipkin and gRPC
https://github.com/openzipkin/brave/tree/master/instrumentation/grpc
URLConnectionSender sender = ...
GrpcTracing grpcTracing = GrpcTracing.create(Tracing.newBuilder()
.sampler(ALWAYS_SAMPLE).spanReporter(AsyncReporter.create(sender)).build());
ManagedChannel peremogaChannel = NettyChannelBuilder.forAddress(peremogaHost, peremogaPort)
.intercept(grpcTracing.newClientInterceptor())
.build();
Server grpcServer = NettyServerBuilder.forPort(8080)
.addService(new AggregationService(asList(peremogaClient, zradaClient)))
.intercept(grpcTracing.newServerInterceptor())
.build().start();
@aiborisov
@mykyta_p

178. Zipkin and REST
build.gradle:
dependencies {
compile 'org.springframework.cloud:spring-cloud-sleuth-zipkin'
compile 'org.springframework.cloud:spring-cloud-starter-sleuth'
...
application.properties:
spring.zipkin.baseUrl=http://zipkin:9411/
# sample 100%
spring.sleuth.sampler.percentage=1.0
...
@aiborisov
@mykyta_p

179. Zipkin : REST and gRPC
@aiborisov
@mykyta_p

180. http://GrpcVsRest.com
#zrada
or
#peremoga
@aiborisov
@mykyta_p

181. Explore More?
Demo: https://github.com/grpcvsrest
@aiborisov
@mykyta_p

182. Explore More?
Demo: https://github.com/grpcvsrest
http://grpc.io
https://github.com/grpc
http://www.grpc.io/docs/quickstart/java.html
gRPC Google group: grpc-io@googlegroups.com
REST: http://google.com/search?q=rest
gRPC
or
REST?
@aiborisov
@mykyta_p

183. Demo UI is written by
Yevgen Golubenko
Software Engineer @ Anomali
• Twitter: @HalloGene_
• github.com/HalloGene
• linkedin.com/in/yevgen-golubenko
@aiborisov
@mykyta_p

184. REST gRPC
@aiborisov
@mykyta_p

185. All about resources
Synchronous and unary
Simplicity first
External fault-tolerance
Production ready
All about APIs
Async and streaming
Performance first
Built-in fault-tolerance
Production ready
REST gRPC
@aiborisov
@mykyta_p

186. All about resources
Synchronous and unary
Simplicity first
External fault-tolerance
Production ready
All about APIs
Async and streaming
Performance first
Built-in fault-tolerance
Production ready
REST gRPC
Be pragmatic,
start with your problem!
@aiborisov
@mykyta_p

187. Questions?
@aiborisov
@mykyta_p