Adam Polak: Architektura oparto o mikroserwisy to temat ogromny. Wszyscy znamy teorię, ale jak to wygląda w praktyce? W jaki sposób ogarnąć kilka niezależnych aplikacji? Co z komunikacją pomiędzy nimi? Podczas prezentacji podzielę się naszymi doświadczeniami, problemami, które napotkaliśmy oraz rozwiązaniami, które znacznie ułatwiły nam cały proces wdrażania tejże architektury.

1. (MICRO?) SERVICES
ARCHITECTURE IN PRACTICE

2. ADAM POLAK
HEAD OF NODE.JS
ADAM.POLAK@TSH.IO
POLAK.ADAM1

3. THEORY

4. ▸ SPECIALIZED SMALL APPS
▸ SEPARATE REPOS
▸ OWN STRUCTURE, API AND LANGUAGE
▸ INDEPENDENT BUILDS, TESTS AND DEPLOYS
▸ EASY TO MAINTAIN BECAUSE OF SMALL CODE
BASE
THEORY
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

5. A BRAND NEW
PROJECT

6. ▸ 5 SERVICES AT START
▸ SPA
▸ 6-7 DEVELOPERS AT START
PROJECT
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

7. ▸ WHAT ABOUT REPOSITORIES?
▸ WHAT ABOUT API?
▸ WHAT ABOUT SETTING UP NEW SERVICE?
▸ WHAT ABOUT DEVELOPMENT?
▸ WHAT ABOUT TESTS?
▸ AND MANY MANY MORE
QUESTIONS?
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

8. MULTIPLE
REPOSITORIES

9. SPA API
Frontend Backend
USE CASE #1

10. USE CASE SUMARY
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE
▸ 2 “SERVICES” - SPA + API
▸ SEPARATE TEAMS
▸ DIFFERENT PROJECT STRUCTURE
▸ TECH PER PROJECT
▸ PRACTICES PER PROJECT

11. LET’S SCALE
IT UP!

12. GATEWAY
PAYMENT
USE CASE #2 - BACKEND
REPORTINGSECURITYSEARCH

13. USE CASE #2 - FRONTEND
SPA GATEWAY

14. THEORY VS REALITY

15. GATEWAY
NODE.JS
1 DEV
SECURITY
PHP
1 DEV
REPORTING
PHP
1 DEV
PAYMENT
.NET
1 DEV
SEARCH
PYTHON
1 DEV
SPA
REACT
1 DEV
THEORY

16. ▸ BEST AVAILABLE TECH FOR GIVEN TASK
▸ ???
PROS
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

17. ▸ 6 DIFFERENT TECH STACKS
▸ NO SHARED CODE = DUPLICATION
▸ 6 DIFFERENT BUILD/DEPLOY PROCESSES
▸ MUCH HARDER TO MOVE DEVS BETWEEN
PROJECTS
CONS
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

18. SPA
REALITY
SHARED
NODE.JS
CODE
SHARED
PHP
CODE
3 DEVS 2 DEVS 1 DEV
REACT
PHPNODE.JS
GATEWAYREPORTINGSEARCH SECURITYPAYMENT

19. ▸ LOWER NUMBER OF TECHS = EASIER
MAINTANANCE
▸ SHARED CODE BETWEEN SAME TECH PROJECTS
▸ SHARED BUILD/DEPLOY PROCESS BETWEEN SAME
TECH
▸ SHARED STRUCTURE BETWEEN SAME TECH
PROJECTS
▸ YOU CAN MOVE FREELY BETWEEN PROJECTS OF
SAME TECH
PROS
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

20. ▸ LOWER PERFORMANCE = WE CANNOT USE THE
BEST POSSIBLE TOOLS
▸ HARDER TO KEEP IT UP TO DATE
CONS
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

21. GATEWAY
REPORTING
SEARCH
SECURITY
PAYMENT
SPA
TSH REALITY = MONOREPO
3 DEVS 2 DEVS 1 DEVS
REACTPHPNODE.JS

22. ▸ EASIEST TO DEVELOP
▸ STILL MODULAR
PROS
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE
▸ LARGER CODE BASE
▸ HARDER TO KEEP BOUNDARIES
CONS

23. THE MOST BORING PART
OF A NEW SERVICE?

24. PLANNING?

25. ARCHITECTURE?

26. SERVICE
BOILERPLATE!

27. security
src
app
grpc
proto
service
container.ts
index.ts
SERVICE SETUP
SAME STRUCTURE
FOR EVERY
SERVICE
+
CUSTOM
MADE
OR
SERVICE
GENERATOR
= SECURITY
SERVICE

28. SETTING UP SERVICE AT TSH
tools create-service —project-name security
/services
/security
/src
/app
/grpc
/proto
/service
container.ts
index.ts

29. FOCUS ON BUSINESS LOGIC
NOT SERVICE STRUCTURE

30. WHAT’S NEXT?

31. SERVICE NEEDS
A CONTRACT

32. POSSIBLE SOLUTIONS
OUR CHOICE

33. WHY DO WE NEED IT?

34. TO GENERATE THINGS!

35. ▸ CLIENTS
▸ TYPES
▸ DTO’S
▸ COMMANDS / HANDLERS / ROUTES SKELETONS
THINGS GENERATED FROM CONTRACTS
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

36. GENERATING FROM PROTO AT TSH
syntax = "proto3";
import "messages/send-notification.proto";
import "messages/acknowledge-notification.proto";
import "messages/get-notifications.proto";
import "messages/get-notification.proto";
package notifications;
service NotificationsService {
rpc sendNotification (SendNotificationRequest) returns (SendNotificationResponse) {}
rpc acknowledgeNotification (AcknowledgeNotificationRequest) returns (AcknowledgeNotificationResponse) {}
rpc getNotifications (GetNotificationsRequest) returns (GetNotificationsResponse) {}
rpc getNotification (GetNotificationRequest) returns (GetNotificationResponse) {}
}

37. GENERATING FROM PROTO AT TSH
tools from-proto —service-name security --generator-type=client
/services
/security
/src
/grpc
/client
index.ts
/types
index.ts
index.ts
/proto
/service
service.ts
tools from-proto —service-name security --generator-type=service

38. GENERATING FROM PROTO AT TSH
/*****************************************/
/* THIS FILE WAS GENERATED */
/* DO NOT TOUCH */
/*****************************************/
import { Observable } from 'rxjs'
import * as grpc from 'grpc'
import { resolve } from 'path'
import { Logger, loadMessageDefinition, toPromise, toObservable } from 'brickvest-js-common'
import {
SendNotificationRequest,
SendNotificationResponse,
AcknowledgeNotificationRequest,
AcknowledgeNotificationResponse,
GetNotificationsRequest,
GetNotificationsResponse,
GetNotificationRequest,
GetNotificationResponse,
GetUnacknowledgedNotificationsCountRequest,
GetUnacknowledgedNotificationsCountResponse,
NotificationStreamToService,
NotificationStreamToClient,
} from '../types'
type ClientDependencies = {
uri: string
logger: Logger
}
class NotificationsClient {
private client: any
constructor(private dependencies: ClientDependencies) {
const messageDefinition = loadMessageDefinition(resolve(__dirname, '../../proto/notifications-service.proto'))
const proto: any = grpc.loadPackageDefinition(messageDefinition).notifications
this.client = new proto.NotificationsService(dependencies.uri, grpc.credentials.createInsecure())
}
public sendNotification(request: SendNotificationRequest): Promise<SendNotificationResponse> {
this.dependencies.logger.info(
`Notifications service client handling: sendNotification (${JSON.stringify(request)})`
)
return toPromise<SendNotificationRequest, SendNotificationResponse>(this.client, 'sendNotification')(request)
}
public acknowledgeNotification(request: AcknowledgeNotificationRequest): Promise<AcknowledgeNotificationResponse> {
this.dependencies.logger.info(
`Notifications service client handling: acknowledgeNotification (${JSON.stringify(request)})`
)
return toPromise<AcknowledgeNotificationRequest, AcknowledgeNotificationResponse>(
this.client,
'acknowledgeNotification'
)(request)
}
public getNotifications(request: GetNotificationsRequest): Promise<GetNotificationsResponse> {
this.dependencies.logger.info(
`Notifications service client handling: getNotifications (${JSON.stringify(request)})`
)
return toPromise<GetNotificationsRequest, GetNotificationsResponse>(this.client, 'getNotifications')(request)
}
public getNotification(request: GetNotificationRequest): Promise<GetNotificationResponse> {
this.dependencies.logger.info(`Notifications service client handling: getNotification (${JSON.stringify(request)})`)
return toPromise<GetNotificationRequest, GetNotificationResponse>(this.client, 'getNotification')(request)
}
public getUnacknowledgedNotificationsCount(
request: GetUnacknowledgedNotificationsCountRequest
): Promise<GetUnacknowledgedNotificationsCountResponse> {
this.dependencies.logger.info(
`Notifications service client handling: getUnacknowledgedNotificationsCount (${JSON.stringify(request)})`
)
return toPromise<GetUnacknowledgedNotificationsCountRequest, GetUnacknowledgedNotificationsCountResponse>(
this.client,
'getUnacknowledgedNotificationsCount'
)(request)
}
public notificationsStream(request: NotificationStreamToService): Promise<Observable<NotificationStreamToClient>> {
this.dependencies.logger.info(
`Notifications service client handling: notificationsStream (${JSON.stringify(request)})`
)
return toObservable<NotificationStreamToService, NotificationStreamToClient>(this.client, 'notificationsStream')(
request
)
}
}
export { NotificationsClient }

39. KEEP SAME CODE STYLE
AND USE STATIC ANALYSIS
TOOLS

41. LOCAL DEVELOPMENT

42. DOCKER
&
DOCKER-COMPOSE

43. DOCKERFILE
FROM node:10.13-alpine
ARG NPM_TOKEN
RUN echo “registry=https://private-repository.com/repository/npm/“ > /root/.npmrc;
RUN echo "always-auth=true" >> /root/.npmrc;
RUN echo "_auth=${NPM_TOKEN}" >> /root/.npmrc;
WORKDIR /dir
COPY . .
RUN npm config set unsafe-perm true
RUN apk add bash
RUN npm install ts-node ts-node-dev typescript -g
RUN npm i
EXPOSE 50050
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

44. SINGLE IMAGE

45. MULTIPLE ENTRYPOINTS

46. DOCKER-COMPOSE
messaging:
image: our-app:latest
container_name: messaging
command: [bash, -c, 'ts-node-dev --poll ./services/messaging/src/index.ts’]
hostname:messaging
volumes: *volumes
depends_on:
- data
gateway:
image: our-app:latest
container_name: gateway
command: [bash, -c, 'ts-node-dev --poll ./services/gateway/src/index.ts']
hostname: gateway
volumes: *volumes
depends_on:
- messaging
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

47. YAML ANCHORS AND REFERENCES TO KEEP IT CLEAN
js:
image: our-app:latest
build:
context: .
dockerfile: docker/dev/Dockerfile
args:
- NPM_TOKEN
volumes: &volumes
- ./:/dir
- /dir/build/
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

48. WHAT ABOUT TESTS?

49. TESTING TROPHY

50. TESTS AS DOCKER CONTAINER
integration-tests:
image: our-app:latest
command:
[
'bash',
'-c',
‘./docker/wait.sh ldap-service 636 ./docker/wait.sh security 50050 npm run integration-tests',
]
volumes: *volumes
depends_on:
- messaging
- security
- ui-gateway
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

51. INTEGRATION TESTS
ARE EASY

52. BUT BEWARE OF
ASYNC

53. WHAT’S WRONG ON THIS PICTURE?
test('Gateway - workflow - create user test', { timeout: 10000 }, async (t: test.Test) => {
const clientSocket = await connectors.getConnector(config.clients.socketIO.type, config.clients.socketIO)
const validateMessage = createSocketValidator(clientSocket)
const connect$ = fromEvent(clientSocket, 'connect')
const mailerClientConfig = config.clients.mailerClient
const emailCountBeforeSending = await getCurrentEmailsCount(mailerClientConfig.mailHogUri)
connect$.subscribe(async () => {
(…)
t.end();
});
});
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

54. WHAT’S WRONG ON THIS PICTURE?
test('Gateway - workflow - create user test', { timeout: 10000 }, async (t: test.Test) => {
const clientSocket = await connectors.getConnector(config.clients.socketIO.type, config.clients.socketIO)
const validateMessage = createSocketValidator(clientSocket)
const connect$ = fromEvent(clientSocket, 'connect')
const mailerClientConfig = config.clients.mailerClient
const emailCountBeforeSending = await getCurrentEmailsCount(mailerClientConfig.mailHogUri)
connect$.subscribe(async () => {
(…)
t.end();
});
});
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

55. WHAT ?!

56. SOLUTION
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE
test('Gateway - workflow - create user test', { timeout: 10000 }, async (t: test.Test) => {
const mailerClientConfig = config.clients.mailerClient
const emailCountBeforeSending = await getCurrentEmailsCount(mailerClientConfig.mailHogUri)
const clientSocket = await connectors.getConnector(config.clients.socketIO.type, config.clients.socketIO)
const validateMessage = createSocketValidator(clientSocket)
const connect$ = fromEvent(clientSocket, 'connect')
connect$.subscribe(async () => {
(…)
t.end();
});
});

57. WHAT ABOUT
NEGATIVE PATHS?

58. YOU CAN CONTROL
SERVICES DIRECTLY
FROM TESTS

59. PASS DOCKER SOCKET TO CONTAINER
js:
image: our-app:latest
build:
context: .
dockerfile: docker/dev/Dockerfile
args:
- NPM_TOKEN
volumes: &volumes
- ./:/dir
- /dir/build/
- /var/run/docker.sock:/var/run/docker.sock
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

60. CONTROL CONTAINERS FROM TESTS CONTAINER
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE
test('Security integration tests - should reconnect to security service', async (t: test.Test) => {
pause(config.containers.security.name)
const payload = {…}
const authenticate = apiGatewayClient.proxy({
payload,
method: 'authenticate',
service: 'security'
})
const timedOut = await Promise.race([waitForTimeout, authenticate])
timedOut === true ? t.pass() : t.fail()
await ensureAreUpAndUnpaused([config.containers.security])
t.end()
})

61. CONTROL CONTAINERS FROM TESTS CONTAINER
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE
test('Security integration tests - should reconnect to security service', async (t: test.Test) => {
pause(config.containers.security.name)
const payload = {…}
const authenticate = apiGatewayClient.proxy({
payload,
method: 'authenticate',
service: 'security'
})
const timedOut = await Promise.race([waitForTimeout, authenticate])
timedOut === true ? t.pass() : t.fail()
await ensureAreUpAndUnpaused([config.containers.security])
t.end()
})

62. CONTROL CONTAINERS FROM TESTS CONTAINER
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE
export const ensureAreUpAndUnpaused = (containers: ContainerConfig[]): Promise<any> => {
const upOrUnpause: Array<Promise<any>> = []
containers.forEach(container => {
if (isPaused(container.name)) {
upOrUnpause.push(unpause(container))
} else if (isDown(container.name)) {
upOrUnpause.push(up(container))
}
})
return Promise.all(upOrUnpause)
}
export const pause = (containerName: string) => shell.exec(`docker pause ${containerName}`)

63. ▸ MONOREPO IS EASIER TO DEVELOP WITH
▸ AUTOMATE PROJECT CREATION
▸ USE CONTRACTS AND GENERATE CODE FROM
THEM
▸ USE DOCKER
▸ FOCUS ON INTEGRATION TESTS
▸ TEST NEGATIVE PATHS
TL/DR
(MICRO?) SERVICES ARCHITECTURE IN PRACTICE

64. QUESTIONS ?

65. THANK YOU