Using Docker for testing can help address many of the common pain points in testing such as inconsistent environments, complex integration testing, and failed tests polluting environments. Docker allows each component like the web server, application server, and database to be containerized so that the full application and environment can be quickly deployed for testing purposes. Integration tests can also be containerized in Docker images and run as part of an automated nightly build pipeline using tools like Jenkins to help ensure continuous integration of the tests and application.

1. Using Docker for
Testing
MUKTA APHALE
ATA GTR 2016, PUNE
@muktaa

2. Who Am I?
• Developer, DevOps Enthusiast
• Passion for technology, innovation and the thirst to keep
learning
• Love to code
• Love to design solutions
• Love to network
• Believe in dreaming big
• Believe in work-life balance
@muktaa

3. Agenda
• Where testing stands today, current challenges of
testing
• What is Docker?
• How can docker help in better automation testing?
• A traditional way of doing integration testing
• Demo of using Docker for testing
• Demo of integrating dockerized tests with your CI
@muktaa

4. Pain Points of Testing
• Unit tests, integration tests, complex integration tests
• UI testing
• Git branching
• Environments
• Failed tests pollute environment
• Deployment dependencies, testing dependencies
@muktaa

5. Docker
@muktaa
Linux
Container Docker Data
Centre,
Docker Cloud,
Docker
Engine,
Docker Hub,
UCP
Benefits:
Speed
Portability
Density
Open
Source
“Can
create
lightweight,
self
sufficient
containers
from
any
application”

6. Docker Applications
• Testing
• Microservices Applications
• Simplifying Development
• Simplifying Deployment
• Production
• CaaS
@muktaa

7. Docker for enabling Testing
• Mimic production environment
• Consistent Environments
• Black Box Testing
• Scalability Testing
• Configuration Testing
• Testing Simplified
@muktaa

8. Deploying for Integration Testing:
Old Way
• Build project
• SCP the build artifact to the
server(s)
• Ssh into the server
• Stop webserver
• Replace the build artifact at the
right path
• Restart webserver
o SCP the tar.gz from the project
to the server(s)
o ssh into the server
o stop tomcat
o remove the “work”, “webapps”,
“shared” and “common” folders
o extract the tar.gz into the
tomcat folder
o start tomcat
@muktaa

9. Integration Testing: Old Way
• Wait for deployment to complete
◦Webserver comes up
• Ensure setup is clean
◦DB Scripts, Env variables, etc
• Get your latest integration test code ready
• Point your integration tests to your newly deployed
setup
• Run integration tests
@muktaa

10. Let’s use Docker…
@muktaa

11. Example
Scenario
• Webserver
• NGiNX
• App Server
• 3 load balanced instances
• Node js
• DB Server
• Redis
@muktaa

12. Output
• Prints the number of times
the page was hit
• Source Code:
https://github.com/muktaa/dock
er-example/
@muktaa

13. Dockerizing Each Component
• Dockerfile for each
component
• Docker-compose.yml
• Build Script
@muktaa

14. Demo
DEPLOY APPLICATION FOR INTEGRATION TESTING
@muktaa

15. Steps
• Git clone https://github.com/muktaa/docker-example/
• Docker-compose build
• Docker-compose up
@muktaa

16. Running Integration
Tests
LETS DOCKERIZE THE INTEGRATION TESTS TOO!
@muktaa

17. Example of Selenium Tests
• https://github.com/muktaa/SeleniumExample
• Ready docker image available:
◦Docker pull selenium-example
• Customize the sample tests, refer to README:
https://github.com/muktaa/SeleniumExample/blob/m
aster/README.md
• Headless Selenium tests
@muktaa

18. Demo
• https://github.com/muktaa/SeleniumExample/blob/m
aster/Dockerfile
• Docker pull muktaa/selenium-example:headless
• Docker run -it -e
TEST_URL=http://54.254.223.84:5555/
muktaa/selenium-example:headless
@muktaa

19. Sample Output
@muktaa

20. Nightly Build
PUTTING
IT
ALL
TOGETHER
TO
WRITE
NIGHTLY
BUILD
JOB
FOR
OUR
DOCKERIZED INTEGRATION
TESTS
@muktaa

21. Jenkins Job
@muktaa

22. Job Configuration
@muktaa

23. Job Build Step 1
#/bin/bash +x
docker-compose --project-name=${JOB_NAME}stop &>
/dev/null || true &> /dev/null
docker-compose --project-name=${JOB_NAME}rm --
force &> /dev/null || true &> /dev/null
docker stop `docker ps -a -q -f status=exited`&> /dev/null
|| true &> /dev/null
docker rm -v `docker ps -a -q -f status=exited`&> /dev/null
|| true &> /dev/null
docker rmi `docker images--filter 'dangling=true' -q --no-
trunc` &> /dev/null || true &> /dev/null
docker-compose build
docker-compose --project-name=${JOB_NAME}up &
@muktaa

24. Job Build Step 2, 3
docker run -itd -v /var/lib/jenkins/workspace/docker-
example/test-report:/usr/share/app/target/surefire-
reports -e TEST_URL=http://54.254.223.84:5555/
muktaa/selenium-example:headless
@muktaa

25. Job Build Steps 3, 4
@muktaa

26. What Next?
• Lots More!
• Running Selenium tests inside Docker
• Using docker swarm to deploy
• Using docker machine to manage hosts for testing
@muktaa

27. References
• http://blogs.plos.org/tech/testing-made-awesome-with-docker/
• https://www.wouterdanes.net/2014/04/11/continuous-integration-using-
docker-maven-and-jenkins.html
• http://making.meetup.com/post/122890386432/steps-towards-automated-
testing-with-docker-and
• https://divan.github.io/posts/integration_testing/
• https://medium.com/@WoloxEngineering/ruby-on-rails-continuous-
integration-with-jenkins-and-docker-compose-8dfd24c3df57#.7vxoq2gfg
• http://anandmanisankar.com/posts/docker-container-nginx-node-redis-
example/
• http://www.conductor.com/nightlight/running-selenium-grid-using-docker-
compose/
@muktaa

28. Thank You!
QUESTIONS?
@muktaa