Knowledge driven micro services presentation from DevConf.cz 2016

1. Knowledge
driven (micro) services
JBCNConf 2016
Maciej Swiderski
Principal Software Engineer
@ JBoss

2. Where is knowledge?
• While building application we tend to focus on
• architecture
• design - modules, UI etc
• code quality
• test cases
• But where is business knowledge in this?

3. Business knowledge
• Data model - the WHAT
• XML
• JSON
• Java
• Business rule definitions - the WHY
• DRL
• Business Process definitions - the HOW
• BPMN2

4. Tools introduction
•Vert.x
•Hazelcast
•Drools and jBPM

5. Vert.x in a Nutshell
“Vert.x is a lightweight, high performance application platform
for the JVM that's designed for modern mobile, web, and
enterprise applications.”

6. Vert.x in a Nutshell
• Polyglot
use your favorite programming language or mix several to
develop applications
• Simplicity
make use of asynchronous APIs without too much hassle
• Scalability
scales using message passing to efficiently utilize your
server cores.
• Concurrency
simple actor-like concurrency model frees you from the
pitfalls of traditional multi-threaded programming.

7. Hazelcast
In memory data grid
Clustered and highly available data distribution
Distributed data structures

8. Vert.x topology
Vert.x instance
Verticle
instance
Verticle
instance
Vert.x instance
Verticle
instance
Clustered
Event Bus
Verticle
instance
Event busEvent bus

9. Knowledge Is Everything
• Open source projects for business systems automation and
management
• Drools
• jBPM
• OptaPlanner
• UberFire
• DashBuilder

10. Knowledge Archives - kjar
• Business assets (data model, processes, rules, decision
tables, forms, etc) are considered source artifacts
• By that means they are packaged as source artifacts - as jars
• Actually as kjars (knowledge archives)
• single difference for kjar is the descriptor - kmodule.xml
• kjar can contain java code as well, alternatively kjar can have
dependencies to other (k)jars

11. Demo description
• Applicant places a loan request
• Bank qualifies given loan based on
• potential risk of giving the loan
• amount of the loan
• duration of the loan
• Bank representative approves or rejects the loan request

12. … into micro services
Apply for loan
service
Evaluate loan
service
Process loan
service

13. Apply for loan service
• Main entry point to the loan request system
• Allow applicant to put loan request that consists of:
• applicant name
• monthly income
• loan amount
• length in years to pay off the loan
Here we provide the WHAT - our data model

14. Evaluate loan service
• Rule based evaluation of incoming loan applications
• Low risk loan
• when loan request is for amount lower that 1000 it’s considered low risk and
thus is auto approved
• Basic loan
• When amount is higher than 1000 and length is less than 5 years - requires
clerk approval process
• Long term loan
• When amount is higher than 1000 and length is more that 5 years - requires
manager approval and might need special terms to be established
Here we provide the WHY - our business rules

15. Process loan service
• Depending on the classification of the loan different bank
departments/teams will be involved in decision making about
given loan request
• Basic loans department
• performs background check on the applicant and either approves or rejects the
loan
• Long term loans department
• requires management approval to ensure a long term commitment can be
accepted for given application.
Here we provide the HOW - our business processes

16. Our architecture
Apply for loan
service
Evaluate loan
service
Process loan
service
Vert.x Event Bus
powered by Hazelcast

17. How does it work?
• Each service is completely self contained
• Knowledge driven services are deployed with kjar
• Services talks to each other by exchanging data - business
data
• Services can come and go as we like - dynamically
increasing or decreasing number of instances of given
service
• no API in the strict sense of its meaning - API is the data

18. Demo
• Deploy service with business processes
• Basic Loan
• Long term load
• Deploy service with business rules
• Deploy service that will place loan applications on
behalf of different users
• Java service
• Java Script service
• Groovy service

19. Our architecture… scaling
Apply for loan
service
Evaluate loan
service
Process loan
service
Vert.x Event Bus
powered by Hazelcast

20. Main take aways
• Knowledge is everything
• Keep in mind when building your services about
• the WHAT
• the WHY
• the HOW
• Always look at the business aspects of the solution you’re
building…. technology, frameworks are just the tools

21. Knowledge driven
micro services
Questions?