Dutch PHP Conference 2016 It's a situation many of us are familiar with: a large legacy application, limited or no tests, slow & manual release process, low velocity, no confidence.... Oh, and management wants new features, fast. But how to proceed? Using examples and lessons learned from a real-world case, I'll show you how to strangle the legacy application with a modern service architecture and build a continuous deployment pipeline to deliver value from the first sprint. On the way, we take a look at testing strategies and various (possibly controversial!) tips and best practices.

1. THE ROAD TO CONTINUOUS
DEPLOYMENT - A CASE STUDY
MICHIEL ROOK

2. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
ABOUT ME
▸ Java, PHP & Scala contractor
▸ PHP since ’99
▸ Maintainer of Phing
▸ Dutch Web Alliance
▸ http://www.linkedin.com/in/
michieltcs
▸ @michieltcs

3. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
THIS TALK
▸ Background
▸ The approach
▸ Process / standards
▸ Build pipelines
▸ Results & lessons learned

5. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
THE SYSTEM - SAN DIEGO
▸ ... or the Big Ball Of Mud
▸ Large legacy monolith
▸ Generates significant income
▸ Slow
▸ Complex, lots of moving parts
▸ Technical debt

6. SAN DIEGO
FRONTEND
MYSQL
DB
SAN DIEGO
BACKEND
LOAD BALANCERS / VARNISH
ITBANEN INTERMEDIAIR NATIONALEVACATUREBANK
SAN DIEGO
FRONTEND
SAN DIEGO
FRONTEND
SAN DIEGO
FRONTEND
SAN DIEGO
BACKEND
SAN DIEGO
BACKEND
SAN DIEGO
BACKEND
MEMCACHE FTP
EXT.
SERVICES
SOLR

7. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
THE SYSTEM - SAN DIEGO
▸ 2.5% code coverage
▸ Fragile tests
▸ Low velocity
▸ Frequent outages / bugs / issues
▸ Frustrated team
▸ Low confidence modifying existing code

8. REFACTOR? REBUILD?

9. A NEW STACK

10. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
THE STACK

11. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
APPROACH
▸ Strangler pattern
▸ Proxy to switch between old/new
▸ Migrate individual pages

12. ORIGINAL
MONOLITH
PROXY
SERVICE
ORIGINAL
MONOLITH
ORIGINAL
MONOLITH
SERVICE SERVICE
SERVICE
PROXY
DB
DB
DB
DB
DB DB

13. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
APPROACH
▸ Services per domain object (job, jobseeker, ...)
▸ Services behind load balancers
▸ Access legacy db’s
▸ Continuous deployment
▸ Containers
▸ Frontends are services

14. SAN DIEGO
ELASTIC
SEARCHLEGACY
DB
JOB
SERVICE
RMQ
ITBANEN INTERMEDIAIR NATIONALEVACATUREBANK
MONGO
DB
ITBANEN
JOBSEEKER
SERVICE
NVBINTERMEDIAI

15. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
PROXY
# Serve job detail page from new code
RewriteRule ^/vacature/.* /app.php [L,PT]
# Proxy php files to php5-fpm
ProxyPassMatch ^/(app.php(/.*)?)$ fcgi://127.0.0.1:9000/opt/webapp/web/$1
# Proxy everything else to SanDiego
ProxyPass / ${SAN_DIEGO__URL} nocanon
ProxyPassReverse / ${SAN_DIEGO__URL}
ProxyPreserveHost On

16. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
FEATURE TOGGLES, A/B TESTS

17. PROCESS

18. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
PROCESS
▸ Scrum, 1 week sprints
▸ TDD / BDD
▸ Definition of Done
▸ Team mindset / experience
▸ Focus on value
▸ Replace old features with new (legacy becomes obsolete)

19. CONTINUOUS EVERYTHING

20. DEV TEST ACCEPTANCE PRODUCTION
DEV TEST ACCEPTANCE PRODUCTION
CONTINUOUS DELIVERY
CONTINUOUS DEPLOYMENT

21. ONLY COMMIT TO MASTER

22. PAIR PROGRAMMING

23. BOY SCOUT RULE

24. QUALITY GATES

25. 100% CODE COVERAGE

26. DASHBOARDS

27. BUILD
PIPELINES

28. AUTOMATE REPEATABLE THINGS

29. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
AUTOMATION
▸ Builds
▸ Testing
▸ Deployments
▸ Orchestration
▸ Config management

30. EVERY COMMIT GOES TO
PRODUCTION

31. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
DEFENSE IN DEPTH
UNIT TESTS
SCENARIOS
INTEGRATION
SMOKE / PERF.
TESTS
MANUAL
TESTING?

32. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
UNIT TESTS
public function testGetById(){
$expectedJob = $this->getJob();
$this->jobRepository->getById($expectedJob->getId())
->shouldBeCalled()
->willReturn($expectedJob);
$this->assertEquals(
$expectedJob,
$this->jobService->getById($expectedJob->getId()
);
}

33. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
SCENARIOS
Scenario: As an API user I need to be able to retrieve a job
Given there is a valid job
When I retrieve a valid job
Then I should get a valid job resource

34. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
BUILDING
<project name="JobService" default="build">
<target name="build">
<delete file="jobservice.tar" quiet="true"/>
<tar destfile="jobservice.tar">
<fileset dir="src">
<include name="*.php"/>
</fileset>
</tar>
</target>
</project>

35. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
DOCKER
FROM php:7.0-apache
ADD vhost.conf /etc/apache2/sites-available/000-default.conf
ADD jobservice.tar /opt/webapp
RUN chown -R www-data:www-data /opt/webapp

36. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
DEPLOYING
PULL IMAGE
REMOVE FROM LOAD BALANCER
STOP CONTAINER
START NEW CONTAINER
WAIT FOR PORT
SMOKE TESTS / HEALTH CHECKS
ADD TO LOAD BALANCER

37. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
DEPLOYING
- name: remove instance from load balancer
haproxy: state=disabled host={{ inventory_hostname }} backend=jobservice
delegate_to: "{{ item }}"
with_items: groups.haproxy
- name: stop & remove old container
docker:
name: jobservice
state: absent
image: jobservice
- name: start container
docker:
name: jobservice
state: present
image: jobservice:{{ BUILD_NUMBER }}
ports:
- "8080:8080"

38. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
DEPLOYING
- name: perform health check
uri:
url: http://localhost:8080/_health
status_code: 200
timeout: 30
return_content: true
changed_when: False
register: result
until: result.content is defined and result.content.find("jobservice") != -1
retries: 10
delay: 3
- name: add instance to load balancer
haproxy: state=enabled host={{ inventory_hostname }} backend=jobservice
delegate_to: "{{ item }}"
with_items: groups.haproxy

39. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
BUILD PIPELINE
node {
stage 'Run tests'
sh "phpunit"
sh "behat"
stage 'Build docker image'
sh "phing build"
sh "docker build -t jobservice:${env.BUILD_NUMBER} ."
sh "docker push jobservice:${env.BUILD_NUMBER}"
stage 'Deploy acceptance'
sh "ansible-playbook -e BUILD_NUMBER=${env.BUILD_NUMBER} -i acc deploy.yml"
stage 'Deploy production'
sh "ansible-playbook -e BUILD_NUMBER=${env.BUILD_NUMBER} -i prod deploy.yml"
}

40. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
BUILD PIPELINE

41. FEEDBACK!

42. RESULTS

43. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
RESULTS
▸ Total build time per service < 10 minutes
▸ Significantly improved page load times
▸ Improved audience stats (time on page, pages per session,
session duration, traffic, seo ranking, etc)
▸ Increased confidence and velocity
▸ Experimented with new tech/stacks (angular, jvm,
eventsourcing)
▸ More fun

44. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
LESSONS LEARNED
▸ Team acceptance
▸ Change is hard
▸ Overhead of weekly sprint; requires discipline
▸ Docker orchestration
▸ Issues with traffic between Amazon <-> on-premise
datacenter
▸ Javascript testing

45. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
LESSONS LEARNED
▸ Experience with new tech
▸ Stability of build pipelines
▸ Management/leadership buy-in
▸ Not enough focus on replacing legacy application

46. THE ROAD TO CONTINUOUS DEPLOYMENT - A CASE STUDY
QUESTIONS & DISCUSSION
Please leave feedback at https://joind.in/talk/4dab5
Thank you!