The document guides developers on creating cloud-native applications using Java, emphasizing concepts like microservices, Kubernetes, and Istio. It outlines key principles for building applications, such as the use of open-source components and simplification of the first-time experience. Additionally, it highlights challenges related to distributed systems, service management, and the use of frameworks for specific application logic.

1. How to develop your first
cloud-native Applications
with Java—
Niklas Heidloff
Developer Advocate, IBM
@nheidloff
Harald Uebele
Developer Advocate, IBM
@Harald_U

2. Continues delivery
→ DevOps
Polyglot microservices
→ Interactions via APIs
Elasticity
→ App stays responsive
Horizontal scalability
→ Distributed systems
What are cloud-native Applications?
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

3. “Microservices are a software
development technique [...]
that structures an application
as a collection of loosely
coupled services.”
Wikipedia
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

4. Run anywhere
→ Kubernetes
Empowered teams
→ Ownership
Fast response times
→ No cold start
Full control
→ Canary rollouts
When to use Microservices?
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

5. New Options → New Challenges

6. Cloud-native applications
provide new capabilities,
which challenge
developers
– New tasks
– Old tasks in new
context
Service discovery and
traffic management
Distributed monitoring,
logging and tracing
Authentication and
authorization between
services
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

7. “Kubernetes (K8s) is an open-
source system for automating
deployment, scaling, and
management of containerized
applications.”
kubernetes.io
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

8. “Istio is an open platform for
providing a uniform way to
integrate microservices,
manage traffic flow across
microservices, enforce
policies and aggregate
telemetry data.”
github.com/istio/istio
@nheidloff @Harald_U

9. “Optimizing Enterprise Java
for a Microservices
Architecture.
[...] by innovating [...] with a
goal of standardization.”
microprofile.io
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

10. How to use all Pieces together?
Kubernetes
Java Enterprise Edition
Istio
Eclipse MicroProfile
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

11. Leverage platforms as
much as possible.
@nheidloff @Harald_U
Use frameworks for app
specific logic.
#IBMDeveloper github.com/nheidloff/cloud-native-starter

12. Design principles for the
end-to-end example
‘cloud-native-starter’
Use only open-source
components for the core
services of the application
Make the first time
experience as simple as
possible
Be able to run the
application in different
environments
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

13. Architecture: End-to-End Example ‘cloud-native-starter’
Web-App
NoSQL / Cloudant
Web-API v1 Articles
Web-API v2 Authors
Web-App
SQL / Db2
OpenID / App ID
LogDNASysdig
Authentication
@nheidloff @Harald_U
Browser Kubernetes with Istio Optional Cloud Services
Ingress

14. Web Experience in ‘cloud-native-starter’

15. Java Image
@nheidloff @Harald_U
Open source stack
OpenJ9 0.12.1
OpenJDK 8u202-b08 from AdoptOpenJDK
Open Liberty 18.0.0.4
MicroProfile 2.1
Dockerfile
#IBMDeveloper github.com/nheidloff/cloud-native-starter

16. Exposing REST APIs
@nheidloff @Harald_U
JAX-RS
Java API for RESTful Web Services
GetArticles.java

17. Exposing REST APIs
@nheidloff @Harald_U
Open API (formerly Swagger)
API description format for REST APIs

18. Consuming REST APIs
@nheidloff @Harald_U
MicroProfile Rest Client
Type-safe approach to invoke RESTful services
AuthorsService.java
AuthorsServiceDataAccess.java

19. Resiliency
@nheidloff @Harald_U
Timeouts and retries
Circuit breaking
Fallback
Fault injection
Service.java

20. Resiliency

21. Traffic Management
@nheidloff @Harald_U
Blue-green deployments
Canary rollouts
A/B testing
ingress.yaml

22. Traffic Management

23. Authentication and
Authorization
@nheidloff @Harald_U
OpenID Connect
Identity layer on top of the OAuth 2.0 protocol
IBM App ID
IBM service to authenticate users and protect APIs
policy.yaml
.env of authentication service

24. Authorization

25. Authorization

26. Authentication

27. Configuration
@nheidloff @Harald_U
MicroProfile Configuration
External configuration of microservices
Service.yaml
CoreService.java

28. Chained invocations Kubernetes
→ 1 service = N pods
Microservices vs monolith
→ Higher complexity
→ Ephemeral
Tracing
Logging
Monitoring
Metrics
Healthchecks
Observability
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

29. Tracing
@nheidloff @Harald_U
OpenTracing
Vendor-neutral APIs and instrumentation for
distributed tracing
Jaeger and Zipkin
Open source distributed tracing systems
server.xml
#IBMDeveloper github.com/nheidloff/cloud-native-starter

30. Distributed Tracing

31. Metrics
@nheidloff @Harald_U
Prometheus
Monitoring system and time series database
GetArticles.java
#IBMDeveloper github.com/nheidloff/cloud-native-starter

32. Metrics

33. LogDNA

34. Sysdig

35. Healthchecks
@nheidloff @Harald_U
MicroProfile Health
Liveness probes and readiness probes
HealthEndpoint.java
Service.yaml

36. Try out the end-to-end
microservices example
cloud-native-starter!
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter

37. Deploying Sample Services
@nheidloff @Harald_U
As easy as ’cf push’
scripts
ibm-scripts
iks-scripts
sh scripts/deploy-authors-nodejs.sh

38. Running the Example App
@nheidloff @Harald_U
Script displays all relevant URLs
sh scripts/show-urls.sh

39. IBM Cloud Kubernetes Service including Istio and Knative

40. IBM Developer
developer.ibm.com
IBM Cloud Lite account
ibm.biz/nheidloff
IBM loves open source
Kubernetes and Istio
OpenJ9 & AdoptOpenJDK
MicroProfile
Open Liberty
Leverage platforms as
much as possible
Use frameworks for app
specific logic
Summary
github.com/nheidloff/cloud-native-starter
@nheidloff @Harald_U #IBMDeveloper github.com/nheidloff/cloud-native-starter