The document provides an overview of microservice architecture using Spring Cloud and Netflix OSS, highlighting critical components such as service discovery, configuration management, and logging. It discusses key technologies including Spring Boot, Eureka, and Hystrix, emphasizing concepts like distributed systems and the importance of production readiness. Additionally, it touches on best practices, including the 12-factor manifesto and tools for logging and tracing in microservice environments.

1. Microservice architecture with
Spring Cloud and Netflix OSS

2. Who am I?
Denis Danov
Software Engineer
&
Consultant at Dreamix Ltd.
www.dreamix.eu

5. Microservice architecture introduction

6. o What is a microservice?
o How to develop microservices?

7. o Microservice properties
n Small and singly focused
n Loosly-coupled and simple
n Technology agnostic
n Independent deployable units
o Distributed system
n Patterns common to all distributed systems
lead to boilerplate code
n configuration management, service
discovery, circuit breakers, intelligent
routing, messaging service etc.

8. o Spring Boot
n Simple infrastructure
n Few dependencies
n REST integrated
n Messaging support
n Uniform operations and metrics
n Logging
n Simple deployment

9. o Spring Cloud
n Distributed/versioned
configuration
n Service registration and
discovery
n Routing
n Service-to-service calls
n Load balancing
n Circuit Breakers
n Distributed messaging
o Netflix OSS
n Archaius
n Eureka
n Zuul
n Feign
n Ribbon
n Hystrix

10. Simple application

11. Production ready
o Having your code done is not the
same as production ready.
o You have to think how to monitor
your application metric in
production.
o Spring Actuator exposes
applciation metric which can be
sent and displayed from another
tool such as Graphite

12. Architecture components
We have our microservice now it
needs a good environment to live in

13. Spring Cloud Dependency
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-
dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>

14. o The 12 Factor manifesto talks
about externalizing that which
changes from one environment to
another from the application itself
o Cloud Config Server takes care to
centralize, externalize, and
dynamically update application
configuration.
Configuration

16. Key points
o Server:
n Dependency:
spring-cloud-config-server
n Annotation:
@EnableConfigServer
@SpringBootApplication
public class CloudConfigApplication
o Client:
n Dependency:
spring-cloud-starter-config
n Properties:
Specify config server address

17. o In the cloud, services are often
ephemeral and it's important to
be able to talk to these services
abstractly, without worrying about
the host and ports for these
services.
o Eureka
Service Discovery

19. Key points
o Server:
n Dependency:
spring-cloud-starter-eureka-server
n Annotation:
@EnableEurekaServer
@SpringBootApplication
public class DiscoveryApplication
o Client:
n Dependency:
spring-cloud-starter-eureka
n Annotation:
@EnableDiscoveryClient
n Properties:
Specify eureka server address
Change config address to service name

20. o Edge services sit as intermediaries
between the clients and the service.
o Proxy requests from an edge-service
to mid-tier services with a
microproxy.
o API gateways are used whenever a
client - like a mobile phone or HTML5
client - requires API translation.
o Zuul, Ribbon, Spring Retry
Edge Services: API gateways

22. Key points
o Server:
n Dependency:
spring-cloud-starter-zuul - proxy
spring-cloud-starter-feign - HTTP REST client
n Annotation:
@EnableZuulProxy
@EnableDiscoveryClient
@SpringBootApplication
public class ApiGatewayApplication
@FeignClient("team-mservice")
public interface CompanyClient

23. o Log aggregation and analysis.
o Essential part of microservice
environment.
o ELK=Elastic+Logstash+Kibana
o Logback
Logging

25. o Distributed tracing lets us trace
the path of a request from one
service to another.
o It's very useful in understanding
where a failure is occurring in a
complex chain of calls.
o Zipkin server and Sleuth
Distributed tracing

27. Key points
o Server:
n Dependency:
zipkin-server
zipkin-autoconfigure-ui
n Annotation:
@EnableZipkinServer
o Client:
n Dependency:
spring-cloud-starter-sleuth
spring-cloud-starter-zipkin
n Configuration:
ZipkinSpanReporter Bean

28. o We often assume that services
will always be up and responding
to requests.
o We need to be a bit more
defensive in any code that
connects to other services.
o There have to be a usefull fallback
mechanism
o Hystrix
Resilience, circuit-breaker

30. Key points
o Server:
n Dependency:
spring-cloud-starter-hystrix-dashboard
n Annotation:
@EnableHystrixDashboard
o Client:
n Dependency:
spring-cloud-starter-hystrix
spring-boot-starter-actuator
n Configuration:
@HystrixCommand(fallbackMethod = "fallback")

31. o All this is a long process of
discovery.
o Capture all this in your Maven
starter with auto-configuration
o It is not needed to reinvent the
wheel.

32. o There are different log
aggregation and analysis
alternatives:
n EKK=Elastic+Kinesis+Kibana (AWS)
n Graylog - nice alerts
Alternatives

33. Kubernetes/Kubeflix
o Language and technology agnostic
o Reduces the need for:
n discovery service
n client-side loadbalancing
n edge-service proxy

34. JHipster microservices

35. Resources
o https://github.com/dndanoff/microservices
o 12 Factor Application
o Spring Cloud Project
o Spring Cloud Docs