Docker es una tecnología que permite empaquetar el software de forma que se pueda ejecutar de forma sencilla y rápida, sin instalación y en cualquier sistema operativo. Es como tener cualquier programa instalado en su propia máquina virtual, pero arranca mucho más rápido y consume menos recursos. Docker está cambiando la forma en la que desplegamos software, pero también está afectando al propio proceso de desarrollo y particularmente al testing.
En este taller pondremos en práctica cómo usar Docker para facilitar la implementación de diferentes tipos de tests y su ejecución tanto en el portátil como en el entorno de integración continua. Aunque las técnicas que veremos se podrán aplicar en cualquier lenguaje de programación, los ejemplos estarán basados en Java y en JavaScript.
2. Testing fácil con Docker · @micael_gallego
@micael_gallego
micael.gallego@urjc.es
@micaelgallego
About me
developer
University professor
Trainer & Consultor
3. Testing fácil con Docker · @micael_gallego
Consultancy / Training
Cloud Computing
WebTechnologies
Extreme Programming
Testing / Git / Jenkins
Software Architecture
Concurrent Programming
Open source elastic platform
for end to end testing
http://codeurjc.es http://elastest.io
Advanced log management
Test orchestration
Test execution comparison
Web and Mobile testing
Security testing
IoT testing
Performance testing
4. Testing fácil con Docker · @micael_gallego
Virtualizacion and Containers
● Developers want to reduce the
differences between local,
continuous integration and
production environments
● Avoiding “It works in my machine”
type of problems
Virtualization Containers
5. Testing fácil con Docker · @micael_gallego
Virtualizacion and Containers
● Virtualization
– Full fledged Virtual Machine (VirtualBox)
– Developer friendly managed VM
(Vagrant)
● Containers
– Docker
7. Testing fácil con Docker · @micael_gallego
VirtualBox
● Developed by Oracle (was owned by Sun
Microsystems)
● Mostly open source, several free (but closed
source) modules
● Windows, Linux and Mac versions
● Advanced Desktop Virtualization
– Shared folders host / guest
– Keyboard and mouse advanced integration
– Graphic 3D acceleration
– Webcam
https://www.virtualbox.org/
9. Testing fácil con Docker · @micael_gallego
VirtualBox
● Manual
– Create an empty virtual machine
– Connect to a ISO (simulating real CD
devide)
– Install a full fledged Operating System
– It is time consuming and it is not easy
to share VM between developers
13. Testing fácil con Docker · @micael_gallego
Vagrant
● It is a command line utility to manage
VMs
● It makes very easy to download and start
a new VM (only with a command)
● Allows to provisioning the new VM with
command provisioning tools (script, chef,
puppet, ansible…)
● VM configuration is specified in a text file,
allowing to share it in the git repository
https://www.vagrantup.com/
14. Testing fácil con Docker · @micael_gallego
Vagrant
● How to create a new VM with ubuntu Xenial
● Vagrant manages certificates and networking
to make easy to connect to the new VM
● By default, working dir is shared
with VM
$ vagrant init ubuntu/xenial64
$ vagrant up
$ vagrant ssh
15. Testing fácil con Docker · @micael_gallego
containers
https://www.docker.com/
16. Testing fácil con Docker · @micael_gallego
Docker
● With VMs you can have the production
environment in your laptop
● But…
– VMs takes minutes to start up
– VMs use (waste?) a lot of resources
(memory and disk space)
17. Testing fácil con Docker · @micael_gallego
Docker
● In a first look, containers can be
considered as “lightweight VMs”
– They contain an isolated environment to run
apps
– Start in milliseconds
– They use only the resources it needs
– A container doesn't have a full fledged
operating system, only the minimal
software to execute apps
19. Testing fácil con Docker · @micael_gallego
Docker
●
Containers and VMs are very different
Virtual Machines Containers
Heavier Lighter
Execute several processes per
Virtual Machine
Usually execute only one process
per container
Ssh connection Direct execution in the container
(rarely needed)
More isolated using hypervisor Less isolated because are
executed using kernel features
Can virtualizeWindows over
Linux
Linux containers must be
executed in linux hosts*
* More on that later
20. Testing fácil con Docker · @micael_gallego
Docker
● To install an application in a linux system you
need all dependencies installed
● Can be incompatibilities between applications
that need different version of the same
dependency
● Docker include in a container all needed
software isolated to the rest of the system
22. Testing fácil con Docker · @micael_gallego
Docker
● Docker containers SO support
– Linux containers
● Very mature technology
● It can be used in any* linux distribution
– Windows containers
● Preliminary technology
● It only can be used in a very recent**
Windows Server version
* Kernel version 3.10 or greather. Published in June 2013
**Windows Server 2016 (Core and with Desktop Experience), Nano Server, andWindows 10
Professional and Enterprise (Anniversary Edition).
23. Testing fácil con Docker · @micael_gallego
Docker
● You can execute linux containers in
any operating system
● It uses virtualization (under the
covers) in Mac and Windows
24. Testing fácil con Docker · @micael_gallego
Docker
● Docker Toolbox for Mac and Windows
– It uses VirtualBox as virtualization
– It is not the same development experience
than in linux
● Docker for Mac and Windows
– Uses native virtualization technology in each
operating system
– Only available in new versions of that SOs
26. Testing fácil con Docker · @micael_gallego
•Docker Image
– Basic template for a container (hard disk of
VM)
– It contains SO (ubuntu), libs (Java) and app
(webapp.jar)
– A container always is started from an image
– If you want to start a new container from an
image that is not in your system, it is
automatically downloaded from Internet
Docker concepts
27. Testing fácil con Docker · @micael_gallego
•Docker Registry
●
Remote service used to store and retrive docker
images
●
It can hold several versions of the same image
●
All versions of the same image are located in the
same repository (like in git)
●
Docker Hub is a public registry managed by Docker
Inc.
●
You can buy private repositories in Docker Hub
●
You can also operate your own private registry
Docker concepts
28. Testing fácil con Docker · @micael_gallego
•Popular repositories in Docker Hub
Docker concepts
29. Testing fácil con Docker · @micael_gallego
•Docker Container
– It is the “equivalent” of a Virtual Machine
– A container is created from a docker image
– When a file is wrote, the image it is not
modified, the container is modified
– It can be started, paused or
stopped
Docker concepts
30. Testing fácil con Docker · @micael_gallego
•Docker Engine
– Local service used to control docker
– Manages images (download, create, pull,
push…)
– Manages containers (start, stop, commit...)
– It can be used with the docker client or
using its REST API
Docker concepts
31. Testing fácil con Docker · @micael_gallego
•Docker client
– Command line interface (CLI) tool to
control docker engine
– It is available when docker is installed in a
system to connect to their local docker
engine
Docker concepts
33. Testing fácil con Docker · @micael_gallego
First steps with docker
Install Docker
– Windows:
●
Microsoft Windows 10 Professional or Enterprise 64-bit:
https://store.docker.com/editions/community/docker-ce-desktop-windows
●
Other Windows versions: https://www.docker.com/products/docker-toolbox
– Linux:
●
Ubuntu: https://store.docker.com/editions/community/docker-ce-server-ubuntu
●
Fedora: https://store.docker.com/editions/community/docker-ce-server-fedora
●
Debian: https://store.docker.com/editions/community/docker-ce-server-debian
●
CentOS: https://store.docker.com/editions/community/docker-ce-server-centos
– Mac:
●
Apple Mac OS Yosemite 10.10.3 or above:
https://store.docker.com/editions/community/docker-ce-desktop-mac
●
Older Mac: https://www.docker.com/products/docker-toolbox
34. Testing fácil con Docker · @micael_gallego
First steps with docker
Hands on…
https://github.com/docker/labs/tree/master/beginner
35. Testing fácil con Docker · @micael_gallego
First steps with docker
Testing if docker is correctly installed
$ docker run hello-world
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
03f4658f8b78: Pull complete
a3ed95caeb02: Pull complete
Digest:
sha256:8be990ef2aeb16dbcb9271ddfe2610fa6658d13f6dfb8bc72074cc1ca369
66a7
Status: Downloaded newer image for hello-world:latest
Hello from Docker.
This message shows that your installation appears to be working
correctly.
...
36. Testing fácil con Docker · @micael_gallego
First steps with docker
Running your first container
$ docker run alpine ls -l
total 48
drwxr-xr-x 2 root root 4096 Mar 2 16:20 bin
drwxr-xr-x 5 root root 360 Mar 18 09:47 dev
drwxr-xr-x 13 root root 4096 Mar 18 09:47 etc
drwxr-xr-x 2 root root 4096 Mar 2 16:20
home
drwxr-xr-x 5 root root 4096 Mar 2 16:20 lib
......
......
37. Testing fácil con Docker · @micael_gallego
First steps with docker
Running your first container
$ docker run alpine ls -l
Command “run”
Creates a new
container and start it
38. Testing fácil con Docker · @micael_gallego
First steps with docker
Running your first container
$ docker run alpine ls -l
Image name
alpine is a minimal linux system
(4.8Mb).The image is downloaded if
not stored in local machine
39. Testing fácil con Docker · @micael_gallego
First steps with docker
Running your first container
$ docker run alpine ls -l
Command “ls -l”
This command will be
executed inside the
running container
40. Testing fácil con Docker · @micael_gallego
First steps with docker
Inspecting the downloaded images
$ docker images
REPOSITORY TAG IMAGE ID
CREATED VIRTUAL SIZE
alpine latest c51f86c28340
4 weeks ago 1.109 MB
hello-world latest 690ed74de00f
5 months ago 960 B
List all images stored in the system
41. Testing fácil con Docker · @micael_gallego
First steps with docker
Executing a container
$ docker run alpine echo "hello from alpine"
hello from alpine
Execute the command “echo” inside the container
42. Testing fácil con Docker · @micael_gallego
First steps with docker
Inspecting containers (executing)
$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED
STATUS PORTS NAMES
a6a9d46d0b2f alpine "echo 'hello from alp" 6 minutes
ago Exited (0) 6 minutes ago lonely_kilby
ff0a5c3750b9 alpine "ls -l" 8 minutes
ago Exited (0) 8 minutes ago elated_ramanujan
c317d0a9e3d2 hello-world "/hello" 34 seconds
ago Exited (0) 12 minutes ago stupefied_mcclintock
It shows containers in the system.
All of them has STATUS Exited.These containers are
not currently executing (but using disk space)
43. Testing fácil con Docker · @micael_gallego
First steps with docker
Interactive commands in containers
$ docker run -it alpine /bin/sh
/ # ls
bin dev etc home lib linuxrc media mnt proc
root run sbin sys tmp usr var
/ # uname -a
Linux 97916e8cb5dc 4.4.27-moby #1 SMP Wed Oct 26 14:01:48 UTC 2016 x86_64
Linux
/ # exit
$
To execute an interactive command it is necessary to
use the option “-it” to connect the console to the
container command
44. Testing fácil con Docker · @micael_gallego
First steps with docker
● Interactive commands in containers
– When you execute a /bin/sh command in
a container it offers a “similar” experience
than a ssh connection
– Buy there are no ssh server neither ssh
client
– It is executing a shell inside the
container
45. Testing fácil con Docker · @micael_gallego
First steps with docker
● Managing containers lifecycle
$ docker run -d seqvence/static-site
Option “-d”
Executes the container
in background
46. Testing fácil con Docker · @micael_gallego
First steps with docker
● Managing containers lifecycle
$ docker ps
CONTAINER ID IMAGE COMMAND
CREATED STATUS PORTS NAMES
a7a0e504ca3e seqvence/static-site "/bin/sh -c 'cd /usr/"
28 seconds ago Up 26 seconds
Container id is
a7a0e504ca3e
This id is used to refer to
this container
STATUS is UP
47. Testing fácil con Docker · @micael_gallego
First steps with docker
● Managing containers lifecycle
– Stop running container
– Delete files of the stopped container
$ docker stop a7a0e504ca3e
$ docker rm a7a0e504ca3e
48. Testing fácil con Docker · @micael_gallego
Net services with docker
● Start container exposing a port
docker run --name static-site
-e AUTHOR="Your Name" -d
-p 9000:80 seqvence/static-site
49. Testing fácil con Docker · @micael_gallego
Net services with docker
● Start container exposing a port
docker run --name static-site
-e AUTHOR="Your Name" -d
-p 9000:80 seqvence/static-site
--name static-site
Specifies a unique name
for the container
50. Testing fácil con Docker · @micael_gallego
Net services with docker
docker run --name static-site
-e AUTHOR="Your Name" -d
-p 9000:80 seqvence/static-site
-e AUTHOR="Your Name"
Set the environment variable
AUTHOR to value “Your Name”
● Start container exposing a port
51. Testing fácil con Docker · @micael_gallego
Net services with docker
docker run --name static-site
-e AUTHOR="Your Name" -d
-p 9000:80 seqvence/static-site
-d
Execute container as deamon
● Start container exposing a port
52. Testing fácil con Docker · @micael_gallego
Net services with docker
docker run --name static-site
-e AUTHOR="Your Name" -d
-p 9000:80 seqvence/static-site
-p 9000:80
Connects the host port 9000 to
the port 80 in the container
● Start container exposing a port
53. Testing fácil con Docker · @micael_gallego
Net services with docker
● Use the service
– Open http://127.0.0.1:9000 in a browser in
your host to access 80 port in container
54. Testing fácil con Docker · @micael_gallego
Net services with docker
● Use the service
– If you are using Docker Toolbox for Mac or
Windows you can’t use 127.0.0.1 IP
– Then you have to open
http://192.168.99.100:9000/ in the browser
$ docker-machine ip default
192.168.99.100
55. Testing fácil con Docker · @micael_gallego
Net services with docker
● Container management
– Stop and remove the container
– Stop and remove a running container
– Remove all running containers
$ docker rm -f static-site
$ docker stop static-site
$ docker rm static-site
$ docker rm -f $(docker ps -a -q)
56. Testing fácil con Docker · @micael_gallego
Managing docker images
● List images in host
Tag is like “version”. Latest is… the
latest ;)
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
seqvence/static-site latest 92a386b6e686 2 hours ago 190.5 MB
nginx latest af4b3d7d5401 3 hours ago 190.5 MB
python 2.7 1c32174fd534 14 hours ago 676.8 MB
postgres 9.4 88d845ac7a88 14 hours ago 263.6 MB
Containous/traefik latest 27b4e0c6b2fd 4 days ago 20.75 MB
...
57. Testing fácil con Docker · @micael_gallego
Managing docker images
● Managing versions
– Download a concrete version
– Download latest version
$ docker pull ubuntu:12.04
$ docker pull ubuntu
58. Testing fácil con Docker · @micael_gallego
Managing docker images
● Searching images in DockerHub
59. Testing fácil con Docker · @micael_gallego
Managing docker images
● Searching images in Docker Store
60. Testing fácil con Docker · @micael_gallego
Managing docker images
● Image types
– Base images
● Images without a parent image
● Examples: Ubuntu, debian, alpine…
● Used by Operating Systems
– Child images
● Base images plus some additional software
● Examples: Nginx, Apache, MySQL...
61. Testing fácil con Docker · @micael_gallego
Managing docker images
●
Official vs User images
– Official images
●
Images created by trusted
companies or communities
– User images
●
Any user can create an account and
upload her own images
62. Testing fácil con Docker · @micael_gallego
Managing docker images
● Create your first
docker image
– We will create a web
application for display
random cat pics using
Python
– Clone following repository
and go to project folder
$ git clone https://github.com/codeurjc/testing-docker
$ cd web-python
63. Testing fácil con Docker · @micael_gallego
Managing docker images
● Create your first image
– You have all source files for the web
application
– But you need Python and Flask to execute
the app
– To execute the web application, you will
create a new image with dependencies
(Python and Flask) and your application code
– Then you can create a new container to
execute your application
64. Testing fácil con Docker · @micael_gallego
Managing docker images
● Dockerfile
– File used to describe a new image
– Specifies
● Base image
● Commands to execute in the image
● Files to include in the image from the
project folder
● Open ports
● Command to execute when start the image
65. Testing fácil con Docker · @micael_gallego
# Select base image
FROM alpine:latest
# Install python and pip
RUN apk add update pypip
RUN pip install upgrade pip
# copy app files
COPY app.py /usr/src/app/
COPY templates/index.html /usr/src/app/templates/
COPY requirements.txt /usr/src/app/
# install Python modules needed by the app
RUN pip install nocachedir r
/usr/src/app/requirements.txt
# tell the port number the container should expose
EXPOSE 5000
# run the application
CMD ["python", "/usr/src/app/app.py"]
66. Testing fácil con Docker · @micael_gallego
Managing docker images
● Dockerfile
– FROM: Base image
– COPY: Copy files from Dockerfile folder
– RUN execute commands
– EXPOSE: Public ports
– CMD: Command to execute when
container is started
https://docs.docker.com/engine/userguide/eng-
image/dockerfile_best-practices/
67. Testing fácil con Docker · @micael_gallego
Managing docker images
● Build the image
– In the folder with a Dockerfile execute
– Executed actions
● Create a new container with base image
● Execute commands and copy app files
● Create a new container with the result
$ docker build -t webapp .
68. Testing fácil con Docker · @micael_gallego
Managing docker images
● Run the new image
– Open http://127.0.0.1:9000/ in the browser
– Windows and Mac users with Toolbox use the IP
$ docker run -p 9000:5000 webapp
* Running on http://0.0.0.0:5000/
(Press CTRL+C to quit)
70. Testing fácil con Docker · @micael_gallego
Managing docker images
● Build the image again
– Change some HTML in templatesindex.html
– Create the image again
– The Dockerfile steps without changes are not re-
executed (are reused from previous execution)
– The image is created very quickly because only
the files copy is perfomed
$ docker build -t webapp .
$ docker run -p 9000:5000 webapp
71. Testing fácil con Docker · @micael_gallego
Volumes
● Volumes
– Allow sharing files between host and container
– Execute a container to show an nonexistent file
– Create a text file
$ docker run alpine cat /data/file.txt
cat: can't open '/data/file.txt': No such
file or directory
$ echo "My file" >> file.txt
72. Testing fácil con Docker · @micael_gallego
Volumes
Volumes
● Mount a host folder inside a container folder
● Host contents replace container contents of
that folder
● Containers can write files in volumes to be
available in the host
$ sudo docker run -v "$PWD":/data alpine
cat /data/file.txt
My file
73. Testing fácil con Docker · @micael_gallego
Volumes
● Volumes
– Docker images use volumes to read files
from host
– Official NGINX container can serve host
files using http
● Serving current folder files ($PWD)
● Go to http://127.0.0.1:9000/file.txt
https://hub.docker.com/_/nginx/
$ docker run -p 9000:80 -v
"$PWD":/usr/share/nginx/html:ro -d nginx
74. Testing fácil con Docker · @micael_gallego
Volumes
● Volumes
– Docker Toolbox for Win or
Mac only allow folders
inside user folder to be
used as volume
– You can use other folders
but have to configure
shared folders in
VirtualBox
https://hub.docker.com/_/nginx/
75. Testing fácil con Docker · @micael_gallego
Volumes
● Developing web app with
volumes
– If you mount your code folder in a
container, when you edit a file, it is
available to the container automatically
– It is not necessary to recreate the image
in each edition
$ docker run -v "$PWD":/usr/src/app/
-p 9000:5000 webapp
76. Testing fácil con Docker · @micael_gallego
•Containers main use cases
– Net service
●
Executed in background long time...
●
Used through network
●
Ex: Databases, web servers...
– Command
●
Execute a single command and stop
●
Read and write files from host with volumes
●
Ex: Java Compiler, jekyll, ffmpeg...
Docker container usage
77. Testing fácil con Docker · @micael_gallego
•Docker for building software
– A container can have all needed environment to
execute a developer tool
– For example, you can have the compiler and the
test dependencies in a container
– You can clone a git repository and execute the
(dockerized) compiler without install any
software in your host
Docker for software developers
78. Testing fácil con Docker · @micael_gallego
•Dockerized Java Maven
– Clone a maven repo
– Compile and exec tests
Docker for software developers
$ git clone https://github.com/codeurjc/testing-docker/
$ cd testing-docker/basic-java-tests
$ docker run --rm -v "$PWD":/data -w /data maven mvn package
79. Testing fácil con Docker · @micael_gallego
•Dockerized Java Maven
Docker for software developers
$ docker run --rm -v "$PWD":/data -w /data maven mvn package
https://hub.docker.com/_/maven/
--rm
Remove container when
execution finish
80. Testing fácil con Docker · @micael_gallego
•Dockerized Java Maven
Docker for software developers
$ docker run --rm -v "$PWD":/data -w /data maven mvn package
https://hub.docker.com/_/maven/
--w
Working dir for the command
81. Testing fácil con Docker · @micael_gallego
•Dockerized Java Maven
Docker for software developers
$ docker run --rm -v "$PWD":/data -w /data maven mvn package
https://hub.docker.com/_/maven/
maven
Official Maven image
82. Testing fácil con Docker · @micael_gallego
•Dockerized Java Maven
Docker for software developers
$ docker run --rm -v "$PWD":/data -w /data maven mvn package
https://hub.docker.com/_/maven/
mvn package
Maven command
83. Testing fácil con Docker · @micael_gallego
•Dockerized Java Maven
– Jar package is generated in /target folder in host
– As container command is executed as root user
(by default), generated files are owned by root.
– Change to your user
Docker for software developers
simple-maven-project-with-tests-1.0-SNAPSHOT.jar
https://hub.docker.com/_/maven/
sudo chown -R username:group target
84. Testing fácil con Docker · @micael_gallego
•Dockerized Node tests
– Clone a test repo
Compile and exec tests
Docker for software developers
$ git clone https://github.com/codeurjc/testing-docker/
$ cd testing-docker/basic-js-tests
$ docker run --rm -v "$PWD":/data -w /data node:9-alpine
npm install; npm test
85. Testing fácil con Docker · @micael_gallego
•Advantages of dockerized dev tools
– Avoid several developers having different
versions of such tools
– It is very easy to test the same code in different
versions (Java 7, Java 8...)
– Reduce tools configuration problems.You can
compile and execute a project easily
– The same tools can be executed in development
laptops and also in CI environment
Docker for software developers
86. Testing fácil con Docker · @micael_gallego
Docker for software developers
87. Testing fácil con Docker · @micael_gallego
•Docker in Continuous Integration
– If you execute dev tools in containers, it is very
easy to compile, test and package in CI
environment
– Only have to execute the same command in
laptop and CI environment
– If a tool changes, only have to change the
command, it is not necessary to install anything
Docker in CI servers
88. Testing fácil con Docker · @micael_gallego
https://jenkins.io/
•Docker in Continuous Integration
Docker in CI servers
– Download LTS version as .war
– We need Java 8 to execute it
$ java -jar jenkins.war
89. Testing fácil con Docker · @micael_gallego
•Docker in Continuous Integration
Docker in CI servers
94. Testing fácil con Docker · @micael_gallego
● Create new Jenkins job
– Create a job with pipeline
– Pipeline:
● Clone git repository
● Compile, test and package Java project
● Copy test results to Jenkins
Jenkins Job
95. Testing fácil con Docker · @micael_gallego
Creamos una nueva
tarea para descargar el
proyecto y ejecutar los
tests
Jenkins Job
97. Testing fácil con Docker · @micael_gallego
Change command
to execute
dockerized maven
command
98. Testing fácil con Docker · @micael_gallego
node {
// Mark the code checkout 'stage'....
stage 'Checkout'
// Get some code from a GitHub repository
git url: 'https://github.com/codeurjc/testing-docker.git'
// Mark the code build 'stage'....
stage 'Build'
// Run the maven build
sh "cd basic-java-tests; docker run --rm -v "$PWD":/data -w /data maven mvn package"
step([$class: 'JUnitResultArchiver',
testResults: '**/target/surefire-reports/TEST-*.xml'])
}
Pipeline
Jenkins Job
99. Testing fácil con Docker · @micael_gallego
Execute the
new job
Jenkins Job
103. Testing fácil con Docker · @micael_gallego
Clic on build to see
details
Jenkins Job
104. Testing fácil con Docker · @micael_gallego
See console output
Jenkins Job
105. Testing fácil con Docker · @micael_gallego
Repository clone
and dockerized
maven execution
Jenkins Job
106. Testing fácil con Docker · @micael_gallego
● Docker pipeline plugin
– Allows a more powerful way to control docker
container from pipelines
– It is not installed by default
Docker in CI servers
https://jenkins.io/doc/book/pipeline/docker/
node {
docker.image('node:7-alpine').inside {
stage('Test') {
sh 'node --version'
}
}
}
111. Testing fácil con Docker · @micael_gallego
● Docker pipeline plugin
Docker in CI servers
node {
stage ('Checkout') {
git url: 'https://github.com/codeurjc/testing-docker.git'
}
stage ('Build') {
docker.image('maven').inside {
sh 'cd basic-java-tests; mvn package'
}
step([$class: 'JUnitResultArchiver',
testResults: '**/target/surefire-reports/TEST-*.xml'])
}
}
sh "cd basic-java-tests; docker run --rm -v "$PWD":/data -w /data maven mvn package"
112. Testing fácil con Docker · @micael_gallego
● Docker pipeline plugin
– To cache Maven repository between executions,
it is possible to mount a volume
Docker in CI servers
node {
stage ('Checkout') {
git url: 'https://github.com/codeurjc/testing-docker.git'
}
stage ('Build') {
docker.image('maven').inside('-v $HOME/.m2:/root/.m2') {
sh 'cd basic-java-tests; mvn package'
}
step([$class: 'JUnitResultArchiver',
testResults: '**/target/surefire-reports/TEST-*.xml'])
}
}
113. Testing fácil con Docker · @micael_gallego
● Advantages of using docker in CI
– CI server just need docker installed, nothing
more
– All tools needed by devs are containerized
– Tools are downloaded (and cached)
automatically when needed
– Several languages/stacks/dependencies can be
used in the same CI server without conflicts
– Sysadmins do not need to give access to CI
server to developers (enforcing security)
Docker in CI servers
114. Testing fácil con Docker · @micael_gallego
● Testing different languages with
Docker
– Testing Node apps with mocha
● https://dzone.com/articles/testing-nodejs-application-
using-mocha-and-docker
– Testing C++ apps with Gtest
● https://github.com/yutakakinjyo/gtest-cmake-example
– Testing Angular apps
● https://jaxenter.com/build-and-test-angular-apps-using
-docker-132371.html
Docker in CI servers
115. Testing fácil con Docker · @micael_gallego
● Testing tools based on docker
– TestContainers
● Define testing dependencies in your JUnit test
● https://www.testcontainers.org/
– Dockunit
● Test your code in several environments
● https://www.npmjs.com/package/dockunit
– Many more...
Docker in CI servers
116. Testing fácil con Docker · @micael_gallego
Docker
Docker container as test dependencies
Docker for tests
117. Testing fácil con Docker · @micael_gallego
Docker
TestContainers
●
Library to write tests in Java with JUnit that allows
you to create and remove container in the context
of a test
●
It’s ideal for integration tests because external
dependencies are managed in the test, not in CI
server scripts
●
It is possible to start any container, but there are
wrappers for BBDD and Web browsers
https://github.com/testcontainers/testcontainers-java
Docker for tests
118. Testing fácil con Docker · @micael_gallego
Docker
TestContainers
●
How to start a generic container in the context of a test
public class RedisBackedCacheTest {
@Rule
public GenericContainer redis =
new GenericContainer("redis:3.0.6").withExposedPorts(6379);
@Before
public void setUp() throws Exception {
Jedis jedis = new Jedis(redis.getIpAddress(),redis.getMappedPort(6379));
cache = new RedisBackedCache(jedis, "test");
}
@Test
public void cacheTest(){
//Test using cache connected to a real Redis database
}
}
https://rnorth.org/junit-integration-testing-with-docker-and-testcontainers
Docker for tests
119. Testing fácil con Docker · @micael_gallego
Docker
TestContainers
●
How to start a Web Browser in the context of a test
public class SeleniumContainerTest {
@Rule
public BrowserWebDriverContainer chrome = new BrowserWebDriverContainer()
.withDesiredCapabilities(DesiredCapabilities.chrome())
.withRecordingMode(RECORD_ALL, new File("target"));
@Test
public void simplePlainSeleniumTest() {
RemoteWebDriver driver = chrome.getWebDriver();
System.out.println("Browser VNC URL: "+chrome.getVncAddress());
driver.get("https://wikipedia.org");
WebElement searchInput = driver.findElementByName("search");
//some asserts...
}
}
https://rnorth.org/better-junit-selenium-testing-with-docker-and-testcontainers
Docker for tests
120. Testing fácil con Docker · @micael_gallego
Docker
TestContainers
●
Execute sample code
$ git clone https://github.com/testcontainers/testcontainers-java-examples
$ cd cd testcontainers-java-examples
$ cd redis-backed-cache/
$ mvn test
//DDBB Tests...
$ cd ../selenium-container
$ mvn test
//Browser Tests...
Docker for tests
Video recorded in
/testcontainers-java-examples/selenium-container/target/recording*.flv
121. Testing fácil con Docker · @micael_gallego
Docker
TestContainers
●
You can execute “mvn test” inside a maven container
●
ButTestContainers lib needs create new containers
●
To allow a container to create new containers in the host,
the file /var/run/docker.sock have to be mounted as
volume
$ docker run --rm -v "$PWD":/data
-v /var/run/docker.sock:/var/run/docker.sock
-w /data maven mvn test
Docker for tests
123. Testing fácil con Docker · @micael_gallego
Docker
Dockerized Jenkins
●
Can we execute do this?
●
CI Server only need Docker installed. All software is
managed using containers
Docker for tests
Jenkins
Maven
Tests
(TestContainers)
Web
Browser
Docker Containers
124. Testing fácil con Docker · @micael_gallego
Docker
Dockerized Jenkins
●
It is possible, but official Jenkins image doesn’t allow it
●
Jenkins container should have docker client installed
●
Image trion/jenkins-docker-client is based on official
jenkins image and install docker client
Docker for tests
docker run -it -e JENKINS_USER=$(id -u)
--rm -p 8080:8080
-v $HOME/.jenkins:/var/jenkins_home
-v /var/run/docker.sock:/var/run/docker.sock
--name jenkins trion/jenkins-docker-client
125. Testing fácil con Docker · @micael_gallego
● Conclusions
– Docker containers are changing the way we
develop, build, test and ship software
– Containers allow developers to use the same dev
tools and execute the project in the same
environment
– Containers ease the configuration and share of CI
servers
– If Continuous Integration is easier to use, more
projects will use it and more test will be executed
Docker in CI servers
126. Testing fácil con Docker · @micael_gallego
Thanks!
Do you have any
question?