Developing Java based microservices

ready for the world of containers

@davsclaus davsclaus

davsclaus.comClaus Ibsen

I was here in 2015

.. and talking about Apache Camel

Claus Ibsen• Principal Software Engineer

at Red Hat

• Apache Camel8 years working with Camel

• Author of Camel in Action books

@davsclaus davsclaus

davsclaus.com

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OS Level Virtualization

Docker Orchestration

PaaS Platform on top of Kubernetes

Services and Tools forKubernetes and OpenShift

Kubernetes

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

Architecture

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

What is Kubernetes?

http://blog.kubernetes.io/2016/06/illustrated-childrens-guide-to-kubernetes.html

fabric8

‣ Tools and Services for value add to Kubernetes and OpenShift

• Management: console, logging, metrics, dashboards, …• Continuous Delivery Workflow• 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

Kubernetes Demo Time

Java Developer

?

Build a Camel Demo

Time

Hello Service

Hello ServiceClient

Hello Service

Hello Service

name=Claus

Hi $name I am $HOSTNAME

Client

Implementation

Client Hello Service

HTTP

ApacheTomcatSpring Boot

Implementation

Hello Service

Client Hello Service

HTTP

Implementation

Client Hello Service

HTTP

from timer to http

logfrom servlet transform

hello service

Hello Service

Client

Ready to run local

Client Hello Service

HTTP 8080

from timer to netty

logfrom servlet transform

hello service

How to build Docker Image?

Maven Project Docker Image

Docker Maven Plugin

Maven Project Docker Maven Plugin Docker Imagebuild

Docker Maven Plugin in pom.xml

Docker Maven Plugin in pom.xml

Build Docker Imagemvn clean install docker:build

Local Docker Repository

Hello Service

Client

Our Demo

Client Hello Service

HTTP 8080

from timer to http

logfrom servlet transform

hello service

Static vs Dynamic Platform

Client Hello Service

HTTP 8080

from timer to http

logfrom servlet transform

hello service

Hardcoded hostname and port

Dynamic Platform

Hello Service

HTTP 8080

Client

from timer to http

logfrom servlet transform

hello service

Kubernetes Service

Kubernetes Service• Network Connection to one or more Pods

• Unique static IP and port (lifetime of service)

Kubernetes Service

HTTP 8080

from timer to http

logfrom servlet transform

hello service

kube proxy

Kubernetes Master

enlisted on deployment

changes

pod

node

pod

node

Kubernetes Servicefrom user point of view

service ip:port

from timer to http

logfrom servlet transform

hello service

pod pod

Service defined in pom.xml

Hello Service

from servlet transform

hello serviceContainer Port =

Inside

Service Port = Outside

Using Kubernetes Service

Client

from timer to http

log

We want to use hello service

How do we do that?

Using Kubernetes Service

• Environment Variables

• Hostname

• Port

Client

from timer to http

log

Service Discovery using DNS is available in newer versions of Kubernetes.

Camel using service

• Use {{service:hello}} Client

from timer to http

log

Ready to run in Kubernetes

Client Hello Service

service:hello

from timer to netty

logfrom servlet transform

hello service

kube proxy

How to deploy to Kubernetes?

Maven Project

How to deploy to Kubernetes?

Maven Project fabric8 Maven Plugin

apply

Deploy - Hello Service

Hello Service

from servlet transform

hello service• mvn -Pf8-local-deploy

Deploy - Client

• mvn -Pf8-local-deploy Client

from timer to http

log

fabric8 Web Console

OpenShift CLI• oc get pods

You can also use CLI from docker &

kubernetes

OpenShift CLI• oc get services

OpenShift CLI• oc logs -f <pod name>

OpenShift CLI No they are not Camel routes,but networking routes.

• oc get routes

Scaling• Change replication controller replicas

Scaling• Service load balancing

Load balancing is random

Angry Pods

1st person shooter - Kill your pods

Zipkin

Distributed message tracing

Zipkin• camel-zipkin (coming in Camel 2.18)

• https://github.com/apache/camel/tree/master/examples/camel-example-zipkin

• kubernetes-zipkin

• https://github.com/fabric8io/kubernetes-zipkin

• https://github.com/fabric8io/kubeflix/blob/master/examples/loanbroker/readme.md

Links

• fabric8 • http://fabric8.io • https://blog.fabric8.io/

• Try kubernetes / fabric8 • http://fabric8.io/guide/getStarted/vagrant.html

@davsclaus davsclaus

davsclaus.com