Yes, you will do cloud-native development. Yes, you will use Java. Yes, you will also work with open programming models like Eclipse MicroProfile and Jakarta EE. Then, what about the cloud platform itself? What about containers? What is the deal with Kubernetes? What is Istio? Do these matter when it comes to code? Do developers need to care? We will take a look at what it means when the code meets the environment, what are the considerations to keep in mind, share what works, and see if cloud-native Java is truly what it is. This is a talk delivered at IBM Think 2020.

1. When Cloud-Native Java
meets Containers,
Kubernetes and Istio
—
Yee-Kang Chang
yeekangc@ca.ibm.com
@yeekangc

2. Cloud-Native Java
Java-based
programming
paradigm that is native
or optimized for a
cloud environment
Containers
“A container is a
standard unit of
software that
packages up code and
all its dependencies so
the application runs
quickly and reliably
from one computing
environment to
another.”
- Docker.com
Kubernetes
“Kubernetes (K8s) is
an open-source
system for automating
deployment, scaling,
and management of
containerized
applications.”
- Kubernetes.io
Istio
“… service mesh is …
the network of
microservices that
make up [distributed
microservice]
applications and the
interactions between
them.
… Istio provides
behavioral insights
and operational
control over the
service mesh as a
whole, offering a
complete solution to
satisfy the diverse
requirements of
microservice
applications.”
- Istio.io© 2020 IBM Corporation 2

3. 3
Cloud-Native Microservices
1. RESTful – Like cattle not pet, communicative
2. Configurable
3. Fault tolerant
4. Discoverable
5. Secure
6. Observable
7. Cloud ready – Heartbeat with cloud infrastructure

4. Eclipse MicroProfile
Config
Fault
Tolerance
JWT
Health
Check
MetricsOpen Tracing
Open API
JAX-RSJSON-PCDIRest Client JSON-B
REST
Foundation
100s of
Microservices
Operation
Focus

5. Microservice Deployment
Config
Fault
Tolerance
JWT
Health
Check
MetricsOpen Tracing
Open API
JAX-RSJSON-PCDIRest Client JSON-B

6. Eclipse MicroProfile
Config
Fault
Tolerance
JWT
Health
Check
MetricsOpen Tracing
Open API
JAX-RSJSON-PCDIRest Client JSON-B
REST
Foundation
100s of
Microservices
Operation
Focus

7. 7
MicroProfile Config with Kubernetes
A B
env:
- name: GREETING
valueFrom:
configMapKeyRef:
name: greeting-config
key: message
kubectl create configmap greeting-config --from-literal
message=Greetings...
@Inject
@ConfigProperty(name = "GREETING")
private String greeting;

8. 8
MicroProfile Health with Kubernetes
A B
readinessProbe:
httpGet:
path: /health/ready
port: 9080
initialDelaySeconds: 15
periodSeconds: 5
failureThreshold: 1

9. 9
MicroProfile Metrics with Kubernetes
A B
@POST
@Counted(name="order", displayName="Order count",
description="Number of times orders
requested.")
public Response orderCoffee(@Valid @NotNull
CoffeeOrder order) {
...
}
Data in OpenMetrics
format
Collect and store data
with Prometheus
Visualize data with
Grafana

10. 10
MP OpenTracing with Kubernetes
A B
@Traced
public void startBrew(CoffeeType
coffeeType) {
...
}
JAX-RS methods
are automatically
traced by default
Distributed tracing
system that supports
OpenTracing data
Deploy and view traces
with Zipkin or Jaeger

11. 11
MicroProfile and Istio
MicroProfile Istio
Traffic Management N/A Routing rules • Use Istio for Blue-Green
deployments, canary
rollouts etc
Fault Tolerance Application layer
Retry, Timeout, Circuit
Breaker, Bulkhead, Fallback
Traffic between services
Retry, Timeout, Circuit
Breaker, Bulkhead
• Istio for broader traffic
management (and fault
injection for testing)
• Application-level fallback
with MicroProfile
Security Secure services with
JWT
Mutual TLS for transport
Origin authentication
with JWT
• Use Istio’s origin
authentication if services
are not secured
Observability or
Telemetry
API to instrument apps
Roll your own
Prometheus, Grafana,
Zipkin, Jaeger etc
Integration with
Prometheus, Grafana,
Jaeger, Zipkin
• OOTB integration
between MP-based
services and Istio
• View service mesh with
Istio’s Kiali

12. THE 12 FACTORS
1. Codebase
2. Dependencies
3. Config
4. Backing Services
5. Build, Release, Run
6. Processes
7. Port binding
8. Concurrency
9. Disposability
10.Dev / Prod parity
11.Logs
12.Admin Processes
THE 12 FACTORS
1. Codebase
2. Dependencies
3. Config
4. Backing Services
5. Build, Release, Run
6. Processes
7. Port binding
8. Concurrency
9. Disposability
10.Dev / Prod parity
11.Logs
12.Admin Processes

13. Istio to manage the
services …
Cloud-Native Java
programming
model like
MicroProfile to code
application
behaviours easily
for Cloud!
Kubernetes to
orchestrate the
environment …
Containerize your
applications …
Cloud-Native Java
+ Containers, Kubernetes and Istio
= A Nice Match
© 2020 IBM Corporation 13

14. Resources Further reading
MicroProfile, the
microservice programming
model made for Istio
https://www.eclipse.org/c
ommunity/eclipse_newsle
tter/2018/september/Micr
oProfile_istio.php
Try it out
Configuring microservices
in Kubernetes
https://openliberty.io/guid
es/kubernetes-
microprofile-config.html
Checking the health of
microservices on
Kubernetes
https://openliberty.io/guid
es/kubernetes-
microprofile-health.html
Managing microservice
traffic using Istio
https://openliberty.io/guid
es/istio-intro.html
Sample implementation
https://github.com/ibm-
cloud-
architecture/refarch-
cloudnative-
kubernetes/blob/micropro
file/docs/istio.md
© 2020 IBM Corporation 14