BCS 2016 "Intro to Microservices (and the Seven Deadly Sins)"

transcript

Introduction to Microservices (And)

The Seven DEADLY SINS OF MicroservicesDaniel Bryant

@danielbryantuk

OpencRedo

(WITH Credit to Tareq Abedrabbo)

The Seven Deadly Sins

1. LUST …

2. GLUTTONY

3. GREED…

4. SLOTH

5. WRATH

6. ENVY

7. PRIDE

07/04/2016 @danielbryantuk

The Seven Deadly Sins (of Microservices)

1. LUST - Using the latest and greatest tech…

2. GLUTTONY - Excessive communication protocols

3. GREED - All your service are belong to us…

4. SLOTH - Creating a distributed monolith

5. WRATH - Blowing up when bad things happen

6. ENVY - The shared single domain fallacy

7. PRIDE - testing in the world of transience

Who Am I?

• Chief Scientist at OpenCredo

ü Agile, Architecture, CI/CD, DevOps

ü Microservices, cloud, containers

ü Driving change through the application of technology and teams

• London Java Community Associate

• InfoQ Editor, DZone MVB, VOXXed, O'REILLy

• MBCS (10+ Years), Ex-academic (PhD AI/Software)

So, What are microservices?

“Loosely coupled service oriented architecture with bounded contexts”

Adrian Cockcroft

“Applications that fit in your head”James Lewis

So, What are microservices?

• Architectural style - build services around biz Capability

• single App composed of multiple services

• Services Running as individual processes, individually deployable

• lightweight external communication (e.g. rest over http)

• Potentially polyglot Language and Data stores

• Minimum centralised management

Monolith vs microservices

martinfowler.com/articles/microservices.html

AKF Scale Cube

Microservices

Microservices Were often a 'Result'

www.slideshare.net/trenaman/javaone-2015-scaling-micro-services-at-gilt

I'm sure a few of you are thinking...

This sounds like distributed objects (CORBA)...

This sounds like component-based software engineering...

This sounds like service-oriented architecture (SOA)...

So, we've done this before?

Oh, Yes...

but this time it's Different...

maybe...

The Perfect Storm in IT?

• collaborative Processes (and increasing requirements for speed)

– Devops, (Lean and Agile)

• Programmable infrastructure

– Config management, Cloud and containers

• Open source

– Download, consume and contribute

Get ready for the (Gartner) rollercoaster...

en.wikipedia.org/wiki/Hype_cycle

Microservices

Opencredo have worked with microservice early adopters...

...And have learnt many lessons

opencredo.com/casestudies/noths-case-study/opencredo.com/casestudies/millenoki-iot/opencredo.com/casestudies/sedex-google-cloud-platform/

The Seven Deadly Sins (of Microservices)

1. Lust - Using THE LATEST and Greatest Tech…07/04/2016 @danielbryantuk

Microservices...

They solve all of our problems, Right?

(If you have silver bullets, watch out for the werewolves)

No... Not necessarily good for speed

skillsmatter.com/skillscasts/6143-microservices-for-speed

Additional Reading!!martinfowler.com/bliki/

MonolithFirst.html

No... Check your architecture/design skills“If you can't build a [well-structured] monolith,

what makes you think microservices are the answer?”

Simon Brown(bit.ly/1n7D0vp)

No... Check your architecture/design skills

No... Operational maturity is vital

martinfowler.com/bliki/MicroservicePrerequisites.html

Microservices are very useful

But check your use case...

...Evaluation is a key skill

Evaluation

“I will postpone using this shiny new framework until my peers have validated the proposed benefits with

rigorous scientific experiments”

- Said by no programmer…ever

Pick Your (Technical) Battles...…

• As Dan McKinley says, “Choose Boring Technology”– Optimize globally across organisation

• Java and Spring (Boot) are perfectly acceptable

• Do you really need containers?

Matt Raible’s Comparison Framework

2. GLUTTONY - Excessive Communication PROTOCOLS07/04/2016 @danielbryantuk

Standardize Across the Organization

• Choose one synchronous protocol

– e.g. JSON over HTTP

• Choose one asynchronous protocol

– e.g. RabbitMQ

Don’t gold-plate, but know your options: ProtoBuf, Thrift, ZeroMQ, MQTT

Enterprise communication (Beam me up?)

www.dzone.com/research/guide-to-enterprise-integration

3. GREED - All your service are Belong to us…07/04/2016 @danielbryantuk

How Do Committees Invent?

“organizations which design systems ... are constrained to produce designs which are copies of the

communication structures of these organizations”

- Melvin Conway, 1968

Dev QA Ops

Hand-offdelaysHand-offdelays

Slowfeedback Slowfeedback

Lackofcohesion, sharedunderstanding andjointaccountability

Front-end Database

Middleware07/04/2016 @danielbryantuk

Technical problems are often people problems...

bit.ly/1L43U4H

Cross-functional Teams

• Spotify (bit.ly/1C46ZKo)– Culture

• Amazon (bit.ly/1F3Dgkm)

– Communication

• Gilt (gi.lt/1rgyWvO)– Strategic alignment

Conway was Telling the Truth... Deal with it!

Final Thoughts for the organisation

Can your business team take advantage of microservices?

Inspiration (for the business)

https://opencredo.com/the-business-behind-microservices-redux/

4. SLOTH - Creating a distributed monolith07/04/2016 @danielbryantuk

Can’t Deploy Services Independently?

Check your ‘bounded contexts’ and/or data ‘fault-lines’

(Also, check you have separated deploy and release)

Can’t Deploy Services Independently?

• Schema-first design

– Michael Bryzek (Gilt): APIdoc

• Consumer-driven Contracts FTW

– Martin Fowler: CDC - A Service Evolution Pattern

Architecture - not a Dirty Word

• Technical leadership (bit.ly/1EUwpLl)

• Communication (bit.ly/1Ia3u8o)

• Promote shared understanding

• ‘Just enough’ up front design

Architectural memes for Microservices

• Design for 'replacability'

• Architectural 'safety' (building cities, not houses)

• Messages

– Event-driven architectures (Event sourcing, CQRS)

– Distributed commit logs (Kafka, Kinesis)

– Actors (Akka, Orleans)

5. WRATH - Blowing up when bad things happen 07/04/2016 @danielbryantuk

Bring in Michael Nygard (Or some monkeys)

Distributed computing - your new best friend

• Notes on distributed systems for young bloods– Jeff hodges (bit.ly/1pKVepz)

• 8 Fallacies of distributed computing

– Sun Microsystems, ROTEM-GAL-OZ (bit.ly/1IEpFC0)

• Distributed systems theory for the distributed systems engineer– Henry Robinson (bit.ly/1qcxqZ3)

OPERATIONAL Concerns: Technical

• Continuous delivery is a microservice prerequisite

– Rapid provisioning

– Basic monitoring

– Rapid application deployment

• Automate, automate, automate...

Operational Concerns: Social

• Failure happens all the time... Get used to it!

• 'Gameday' or 'Disaster in recovery testing' (Real) Scenarios

• Failure injection testing (FIT):

– Building 'Failure as a Service' at Netflix without the Simian Army

Share the pain...

“Developer-on-call”An occasional spike to the head

is a good thing...

...metaphorically speaking

• You build it, you run it– Accountability

– Shared responsibility

– Communication

6. ENVY - The shared SINGLE domain fallacy07/04/2016 @danielbryantuk

One Model to Rule Them All...

• One 'Canonical' model…– Breaks encapsulation

– Introduces coupling

• Know your DDD– Entities

– Value Objects

– Aggregates and Roots

But... how do I generate Reports?

• Aggregated reporting pattern

– Pull by service

• Data Pumps

– Push (Event sourcing?)

7. PRIDE - testing in the world of transience07/04/2016 @danielbryantuk

People are surprisingly quiet about this...

07/04/2016 @danielbryantukmartinfowler.com/articles/microservice-testing/

Testing With Microservices is Difficult...

• Invest in your build pipeline testing

– Serenity BDD

– Hoverfly & Wiremock / Saboteur

– Jenkins Performance plugin

Testing With Microservices is Difficult...

• Do it in production(?)

– Netflix

– Hailo

– Gilt

• This is an advanced pattern!– Automation is essential!

Summary

https://skillsmatter.com/members/danielbryantuk#skillscasts

https://www.youtube.com/playlist?list=PLzA2sNPAqK1RcVGsFl7up4Phqs6LlmmiY

http://www.infoq.com/presentations/7-sins-microservices

https://opencredo.com/blog/https://opencredo.com/tag/microservices/http://muservicesweekly.com/

http://www.infoq.com/author/Daniel-Bryant

THANKS...

@danielbryantuk

daniel.bryant@opencredo.com

Credit to Tareq Abedrabbo and the OpenCredo Team for inspiration/guidance

Big Thanks to our clients: Noths.com, Sedex and Millenoki