The so-called experts are saying microservices and containers will change the way we build, maintain, operate, and integrate applications. This talk is intended for Java developers who wants to hear and see how you can develop Java microservices that are ready to run in containers. In this talk we will build a set of Java based Microservices that uses a mix of technologies with Apache Camel, Spring Boot and WildFly Swarm. You will see how we can build small discrete microservices with these Java technologies and build and deploy on the Kubernets container platform. We will discuss practices how to build distributed and fault tolerant microservices using technologies such as Kubernetes Services, Camel EIPs, and Netflixx Hysterix. And the self healing and fault tolerant aspects of the Kubernetes platform is also discussed and demoed when we let the chaos monkeys loose killing containers. This talk is a 50/50 mix between slides and demo. The talk was presented at JDKIO on September 13th 2016.

1. Developing
Java based microservices
ready for the world of containers
@davsclaus
davsclaus
davsclaus.com
Claus Ibsen

2. Claus Ibsen
• Principal Software Engineer
at Red Hat
• Apache Camel
8 years working with Camel
• Author of
Camel in Action books
@davsclaus
davsclaus
davsclaus.com

6. ?

7. ?

8. OS Level Virtualization
Docker Orchestration
PaaS Platform on top of
Kubernetes
Services and Tools for
Kubernetes and OpenShift

9. Kubernetes

10. Kubernetes
‣ Open Source orchestration platform for Docker
containers
• Rewrite of Google’s internal framework “Borg”
‣ Declarative specification of a desired state
‣ Self-healing
‣ Service discovery
‣ Scheduling across hosts
‣ Replication

11. Architecture

12. Key Concepts
‣Nodes
• Worker machine (physical or VM) running pods
‣Pods
• Collection of one or more Docker containers
‣Replication Controller
• Creates and takes care of Pods
‣Services
• Network Proxy for a collection of Pods
‣Labels
• Grouping and organization of Objects
‣Namespaces
• Virtual clusters backend by same physical cluster

13. Pod
‣ Collection of Docker containers running on the same
host.
‣ Pods have unique IPs
‣ Containers in a Pod ….
• …. share the same IP address
• …. can reach each other via local ports
• …. can share data via volumes
‣ Pods can have one or more Labels

14. Replication Controller
‣ Controls Pods selected by Labels
‣ Ensures that a specified number of Pod replicas is
running
‣ Holds Pod templates for creating new Pods
‣ Autoscaling
‣ Rolling Updates

15. Service
‣ View on a set of Pods with single
IP address and port
‣ Pods are selected by Label
‣ Services are referenced by
environment variables
‣ Service addresses stay stable
• Pods come and go (with different IPs)

16. What is Kubernetes?
http://blog.kubernetes.io/2016/06/illustrated-childrens-guide-
to-kubernetes.html

17. https://fabric8.io/

18. fabric8
‣ Opinionated microservices platform based on
Docker, Kubernetes and Jenkins
• Management: console, logging, metrics, dashboards, …
• Continuous Delivery Pipeline
• iPaaS: Camel route visualization, API registry, Messaging as
a Service, …
• Tools: Kubernetes/OpenShift build integration, Kubernetes
component test support, CDI extensions
• Quickstarts: Ready to use examples, also available as
Maven archetypes

19. Kubernetes
Demo Time

20. Java Developer
?

21. Build a
Camel Demo
Time

22. Source Code
https://github.com/davsclaus/fabric8-hello

23. Hello Service
Hello
Service
Client

24. Hello Service
Hello
Service
name=Claus
Hi $name I am $HOSTNAME
Client

25. Implementation
Client Hello Service
HTTP
WildFy
Swarm
Spring Boot WildFly Swarm

26. Implementation
Hello
Service
Client Hello Service
HTTP

27. Implementation
Client Hello Service
HTTP
from timer
to http
log
from undertow
transform
helloservice

28. Spring Boot Starter

29. Client

30. WildFly Swarm Generator

31. Hello Service

32. Hello Service

33. Ready to run local
Client Hello Service
HTTP 8080
from timer
to netty
log
from undertow
transform
helloservice

34. How to build Docker Image?
Maven Project Docker Image

35. Docker Maven Plugin
Maven Project
Fabric8 Maven
Plugin
Docker Image
build
https://maven.fabric8.io

36. Fabric8 Maven Plugin
https://maven.fabric8.io

37. Install
fabric8-maven-plugin
mvn io.fabric8:fabric8-maven-plugin:3.1.37:setup
https://maven.fabric8.io

38. Fabric8 Maven Plugin

39. Build Docker Image
mvn package fabric8:build

40. Local Docker Repository
Hello Service
Client

41. Our Demo
Client Hello Service
HTTP 8080
from timer
to http
log
from undertow
transform
helloservice

42. Static vs Dynamic Platform
Client Hello Service
HTTP 8080
from timer
to http
log
from undertow
transform
helloservice
Hardcoded
hostname and port

43. Dynamic Platform
Hello Service
HTTP 8080
Client
from timer
to http
log
from undertow
transform
helloservice
Kubernetes
Service

44. Kubernetes Service
• Network Connection to one or more Pods
• Unique static IP and port (lifetime of service)

45. Kubernetes
Service
HTTP 8080
from timer
to http
log
from undertow
transform
helloservice
kubeproxy
Kubernetes
Master
enlisted on deployment
changes
pod
node
pod
node

46. Kubernetes Service
from user point of view
service ip:port
from timer
to http
log
from undertow
transform
helloservice
pod pod

47. Out of the box service
Maven artifactId
WildFly Swarm
HTTP port

48. Custom Configured Service
service.yml
Container Port =
Inside
Service Port =
Outside
Service Name

49. Using Kubernetes
Service
Client
from timer
to http
log
We want to use hello service
How do we do that?

50. Using Kubernetes
Service
• Environment Variables
• Hostname
• Port
Client
from timer
to http
log
Service Discovery using DNS is available
in newer versions of Kubernetes.

51. Service using ENV
• Use ENV Client
from timer
to http
log

52. Service using DNS
• Use DNS Client
from timer
to http
log

53. Service using DNS
Client
from timer
to http
log
Kubernetes
Service

54. Ready to run in Kubernetes
Client Hello Service
{{service:hello}}
from timer
to netty
log
from undertow
transform
helloservice
kubeproxy

55. How to deploy to
Kubernetes?
Maven Project

56. How to deploy to
Kubernetes?
Maven Project
fabric8 Maven
Plugin
run

57. Deploy - Hello Service
Hello Service
from undertow
transform
helloservice
• mvn fabric8:run

58. Deploy - Client
• mvn fabric8:run Client
from timer
to http
log

59. Running Kubernetes
Locally
• MiniKube
• MiniShift
• Vagrant
• OpenShift CDK
https://fabric8.io/guide/getStarted/index.html

60. Running fabric8
• Download gofabric8
https://github.com/fabric8io/gofabric8/releases
• Start fabric8
gofabric8 start --minishift --console --memory=2000
https://fabric8.io/guide/getStarted/minishift.html

61. fabric8 Web Console
minishift service fabric8

62. OpenShift CLI
• oc get pods
You can also use CLI from
docker &
kubernetes

63. OpenShift CLI
• oc get service

64. OpenShift CLI
• oc logs -f <pod name>

65. • minishift service hello
Access Service
from your laptop

66. Scaling
• Change deployment replicas

67. Scaling
• Service load balancing
Load balancing
is random

68. Angry Pods
1st person shooter - Kill your pods

69. Links
• fabric8
• http://fabric8.io
• Demo source code
• https://github.com/davsclaus/fabric8-hello
• Try kubernetes / fabric8
• https://fabric8.io/guide/getStarted/minishift.html
• Videos, blogs and more
• https://fabric8.io/community/index.html
@davsclaus
davsclaus
davsclaus.com