1. Be Whisked Away with a Raspberry PI, Java, and OpenWhisk
Luc Desrosiers
Certified IT Architect
Session CON2758

2. About me 20 years in IT – Development, Integration, Cloud
IT Architect who loves to write code
Java enthusiast since using Servlet Express back in 1998
Cloud, IoT and Cognitive computing are areas that I am passionate about
Probably lost my hair to a program that would not compile…

3. What can you expect to get from this session?
An understanding of serverless computing and OpenWhisk
An early view on some usage patterns and how it can be used to complement your application design
A quick way to get started experimenting with OpenWhisk
And finally,
A demonstration of an IoT solution integrated with OpenWhisk

4. What is OpenWhisk?
OpenWhisk is a Cloud platform to execute code in response to events
OpenWhisk is an Open Source project released by IBM
Supports many language including Java
Based on the serverless concept …

5. What is serverless ?
OpenWhisk is a Cloud platform to execute code in response to events
Serverless is about removing infrastructure from the equation
It is about focusing on business logics, not thread pools
Often associated to Function-as-a-Service

6. What if I need to scale this?
The transition from micro services…
Service
Discovery
1 Docker Container
1 Docker Container
Microservice
REST
/HTTP VM
REST
/HTTP
API VM
App Servers
Publish
App Servers
Microservice
Microservice VM
App Servers
App Servers
API
Microservice
Microservice
Publish
NodeJS
instance
NodeJS
instance
broker
Subscribe
What if I need to scale this?
NodeJS
instance
Microservice
NodeJS
instance
Microservice
Microservice
NodeJS
instance

7. to serverless… Serverless technology handles the burst
Service
Discovery
1 Docker Container
1 Docker Container
Microservice
REST
/HTTP VM
REST
/HTTP
API VM
Publish
Microservice
Microservice VM
API
serverless container
Trigger
Publish
Action
Serverless
technology handles the burst
Microservice
broker
Trigger
What if I need to scale this?
Subscribe
Action
Microservice
Microservice

8. So what does it look like ?
Event
Actions are only alive for the
duration of the execution!
Trigger
Action
Trigger +
Action = Rule

9. OpenWhisk Overview
Language supported:
NodeJS
Swift
Java
Python
Docker

10. Where does it fit ?
Serverless is a piece of the puzzle… not a complete solution
Triggers and Back-end Services are not necessarily serverless
Someone has to hold the state after all…
Back-end as a Service
Event
Generator
Serverless
components UI
Components

11. Serverless and the 12 Factor App?
Twelve Factor App was created as a methodology for building SaaS…
II. Dependencies
Explicitly declare and isolate dependencies
III. Config
Store config in the environment
IV. Backing services
Treat backing services as attached resources
VI. Processes
Execute the app as one or more stateless
processes
VII. Port binding
Export services via port binding
VIII. Concurrency
Scale out via the process model
IX. Disposability
Maximize robustness with fast startup and graceful shutdown

12. OK, what about usage patterns ?
Serverless technologies are still new… patterns have yet to emerge
Simplicity should be the focus of each function
May need significant refactoring of existing code to minimize dependencies…
However there are some architecture patterns where serveless fits nicely…

13. Mobile and Web Backend as a Service
Sequence
Business Logic
Action
/whisk/push
Backend
Service
API Gateway
Trigger
Web App
Benefits:
Clear delineation of business and controller logic
Produces discreet reusable action that can be assembled as a sequence

14. The analytics platform
Data processing pipeline
Cloudant
DB A
IoT
Events
Quality Control
Event
Persister
/whisk/cloudant
Trigger
Change Listener
Data
Enrichment
Cloudant
DB A
/whisk/weather
Change
Feed
Benefits:
Database change can trigger other actions
Functionality can be extended easily

15. The DevOps pipeline Benefits: Improve communication
Sequence
GitHub
Business Logic
Action
/whisk/slack
Backend
Service
Git
Data
Feed
Benefits:
Improve communication
Clean extension to the build pipeline

16. Some considerations Avoid heavy-weight functions Harder to debug
Harder to reuse
Trigger do not guarantee order of processing…
Message affinity is bad… avoid it at all costs
Plan how your input and output are designed to maximize reuse
Ability to re-use an action depends on the assumption it is making about its input
Assert aggressively!

17. Now, how can you get started?
Get familiar with the OpenWhisk command line interface
Create a basic Java Action
Deploy to Bluemix or locally

18. OpenWhisk Command Line
Installing OpenWhisk CLI can be found here:
wsk trigger create <trigger-name>
1. Creating a trigger
wsk package create <package-name>
2. Creating a package
wsk action create <package>/<action> <Jar File>.jar
3. Creating an action
wsk package bind /whisk.system/websocket <bind-name> -p uri ws://<url>
4. Create a binding for an action
wsk rule create <rule-name> <trigger> <action>
5. Create a rue for triggering an action

19. Creating a Basic Java Action
The entry point for the Action must follow this signature
Note: If the JAR file has more than one class with a main method matching required signature, the CLI tool uses the first one reported by jar -tf

20. Deploying to Bluemix

21. What is available out of the box?
Here are some of the provided package of actions and feed you can use to get started:
Weather data
slack
github
Cloudant
Watson
Push
Notifications
Alarms

22. Where does the Raspberry Pi come in?
Serverless technology Is based on triggering action based on events
A robot including sensors generates lots of events
Objective was to see how serverless could be integrated

23. The Anatomy of an IoT tank
Cloudant
IoT-Tank
Visual Recognition
Send image &
sensor data
Change Listener
Image Analysis
Start &
stop session
Start Session
IoT Tank Vision
IoT Bridge
Stop Session
Save IoT data
Watson IoT
Foundation
OpenWhisk

24. IoT tank – Communication Layer
Sending events:
Pi4J – GPIO Control
IBM Watson IoT Foundation – IoT integration
Cloudant – Image persistence
JRPiCam – Pi Camera Control
Receiving commands:

25. Wrap-up
Serverless technology is a key part of a microservices architecture
OpenWhisk reduces the operational burden
Patterns are still emerging but the technology works great with:
Web or Mobile application
Analytics
DevOps pipeline
Getting started is easy and quick… Try it for yourself! 

26. Thank You! Some references…
IBM Hybrid Cloud solution guide:
Building a Hybrid Cloud with Bluemix
Bluemix blog 
Getting Started with OpenWhisk:
Accessing the code:
Luc Desrosiers | | Twitter: Luc_At_IBM

27. The inner-workings of OpenWhisk