The Seven DEADLY SINS OF Microservices
Daniel 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
12/08/15
@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
12/08/15
@danielbryantuk

Who Am I?
• Principle Consultant at OpenCredo
ü Agile, CI/CD, DevOps
ü Microservices and cloud
ü Docker, Mesos and Kubernetes
• London Java Community Associate
• Adopt OpenJDK and JSR
• InfoQ Editor and DZone MVB
12/08/15
@danielbryantuk

So, What is a microservice?
“Loosely coupled service oriented architecture
with bounded contexts”
Adrian Cockcroft
“Applications that fit in your head”
James Lewis
12/08/15
@danielbryantuk

1. Lust - Using THE LATEST and Greatest Tech…
12/08/15
@danielbryantuk

Microservices...
They solve all of our problems, Right?
12/08/15
@danielbryantuk

No... Not necessarily good for speed
12/08/15
@danielbryantuk
skillsma7er.com/skillscasts/6143-­‐microservices-­‐for-­‐speed
AddiConal
Reading!!
marCnfowler.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)
12/08/15
@danielbryantuk

No... Check your architecture/design skills
12/08/15
@danielbryantuk

No... Operational maturity is vital
12/08/15
@danielbryantuk
marCnfowler.com/bliki/MicroservicePrerequisites.html

Microservices are very useful
But check your use case...
...Evaluation is a key skill
12/08/15
@danielbryantuk

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
12/08/15
@danielbryantuk

Pick Your (Technical) Battles...…
• As Dan McKinley says, “Choose Boring Technology”
– Optimize globally across organisation
• Java and Spring (Boot) are perfectly acceptable
• ... As are tomcat/jetty
12/08/15
@danielbryantuk

Matt Raible’s Comparison Framework
12/08/15
@danielbryantuk

2. GLUTTONY - Excessive Communication PROTOCOLS
12/08/15
@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
12/08/15
@danielbryantuk

Enterprise communication (Beam me up?)
12/08/15
@danielbryantuk
www.dzone.com/research/guide-­‐to-­‐enterprise-­‐integraCon

3. GREED - All your service are Belong to us…
12/08/15
@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
12/08/15
@danielbryantuk

12/08/15
@danielbryantuk
Dev
QA
Ops
Hand-­‐off
delays
Hand-­‐off
delays
Slow
feedback
Slow
feedback
Lack
of
cohesion,
shared
understanding
and
joint
accountability
Front-­‐end
Database
Middleware

12/08/15
@danielbryantuk

Technical problems are often people problems...
12/08/15
@danielbryantuk
bit.ly/1L43U4H

Cross-functional Teams
• Spotify (bit.ly/1C46ZKo)
– Culture
• Amazon (bit.ly/1F3Dgkm)
– Communication
• Gilt (gi.lt/1rgyWvO)
– Strategic alignment
12/08/15
@danielbryantuk

Conway was Telling the Truth... Deal with it!
12/08/15
@danielbryantuk

Final Thoughts for the organisation
Can your business team take advantage of microservices?
12/08/15
@danielbryantuk

Inspiration (for the business)
12/08/15
@danielbryantuk
bit.ly/1Mi3hDi

4. SLOTH - Creating a distributed monolith
12/08/15
@danielbryantuk

Can’t Deploy Services Independently?
Check your ‘bounded contexts’ and/or data ‘fault-lines’
(Also, check you have separated deploy and release)
12/08/15
@danielbryantuk

Can’t Deploy Services Independently?
• Schema-first design
– Michael Bryzek (Gilt): APIdoc
• Consumer-driven Contracts FTW
– Martin Fowler: CDC - A Service Evolution Pattern
“CDC is BDD for microservices”
12/08/15
@danielbryantuk

Architecture - not a Dirty Word
• Technical leadership (bit.ly/1EUwpLl)
• Communication (bit.ly/1Ia3u8o)
• Promote shared understanding
• ‘Just enough’ up front design
12/08/15
@danielbryantuk

5. WRATH - Blowing up when bad things happen
12/08/15
@danielbryantuk

Bring in Michael Nygard (Or some monkeys)
12/08/15
@danielbryantuk

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)
12/08/15
@danielbryantuk

OPERATIONAL Concerns: Technical
• Continuous delivery is a microservice prerequisite
– Rapid provisioning
– Basic monitoring
– Rapid application deployment
• I.E. Agile & DevOps
12/08/15
@danielbryantuk

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
12/08/15
@danielbryantuk

Share the pain...
12/08/15
@danielbryantuk

“Dev-on-call”
An occasional spike to the head
is a good thing...
...metaphorically speaking
• You write it, you run it
– Accountability
– Shared responsibility
– Communication
12/08/15
@danielbryantuk

6. ENVY - The shared SINGLE domain fallacy
12/08/15
@danielbryantuk

One Model to Rule Them All...
• One model…
– Breaks encapsulation
– Introduces coupling
• Know your DDD
– Entities
– Value Objects
– Aggregates and Roots
12/08/15
@danielbryantuk

But... how do I generate Reports?
• Aggregated reporting pattern
– Pull by service
• Data Pumps
– Push (Event sourcing?)
12/08/15
@danielbryantuk

7. PRIDE - testing in the world of transience
12/08/15
@danielbryantuk

People are surprisingly quiet about this...
12/08/15
@danielbryantuk
marCnfowler.com/arCcles/microservice-­‐tesCng/

Testing With Microservices is Difficult...
• Invest in your build pipeline testing
– Serenity BDD
– Wiremock / Saboteur
– Jenkins Performance plugin
12/08/15
@danielbryantuk

Testing With Microservices is Difficult...
• Do it in production(?)
– Netflix
– Hailo
– Gilt
• This is an advanced pattern!
– Automation is essential!
12/08/15
@danielbryantuk

Summary
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
12/08/15
@danielbryantuk

12/08/15
@danielbryantuk

THANKS...
@danielbryantuk
daniel.bryant@opencredo.com
https://www.parleys.com/tutorial/seven-deadly-sins-microservices
(Credit to Tareq Abedrabbo for inspiration/guidance)
12/08/15
@danielbryantuk