Learn how to build web service using docker, it is intermediate knowledge of docker. CodingWithMe style for 90 minutes

1. Larry cai
Charlie Zha zysimplelife AT gmail.com

2. Precondition
 You need finish/understand the basic docker knowledge
in
http://www.slideshare.net/larrycai/learn-docker-in-90-minutes
 What is docker
 Command : pull/run/images/ps ..
 Interactive and daemon mode
 Build with Dockerfile
Build Service with Docker in 90 minutes2 09/16/16

3. Agenda
 Docker Revisit
 Exercise 1: Revisit Dockerfile
 Exercise 2: Manage data in container (-v)
 Exercise 3: Manage data in container
from another
 Exercise 4: Link containers (--name/--
link)
 Exercise 5: Docker in Docker
 Exercise 6: Build service together
(haproxy+2 tomcat)
 Exercise 7: Docker Compose
Build Service with Docker in 90 minutes3 09/16/16
Docker HostDocker Host
HAProxy
(Load Balancer)
Tomcat
(web1)
Tomcat
(web1)
808080
8080
Web Service
Tomcat
(web2)
Tomcat
(web2)
8080
ClientClient

4. Environment Preparation
 Boot2docker Installer (27M)
 Contains latest docker already, fast
 Container persistence via disk automount on /var/lib/docker
 Add proxy /var/lib/boot2docker/profile if needed
 $ sudo vi /var/lib/boot2docker/profile
 export http_proxy=<your proxy>
 $ sudo /etc/init.d/docker restart
 $ docker -v
 User/Passwd: docker/tcuser
Build Service with Docker in 90 minutes4 09/16/16
http://boot2docker.io/

5. Docker Revisit
 Docker is an open-source engine that automates the
deployment of any application as a lightweight, portable,
self-sufficient container that will run virtually anywhere.
Build Service with Docker in 90 minutes5 09/16/16
 Based on LXC (Linux
Container), easy to use.
 Similar to VM as end-
user with different
features

6. Manage Data in Container
 Container as a Service and Data needs persistency
 Load balancer,App, Database, Data storage
 Share data from host by mount a Host
Directory as a DataVolume
 VOLUME [ “/var/data” ] # in Dockerfile
 -v host:guest # in docker run
 Share data from another Data-only container
 --volumes-from data-container
 Backup/Restore Data-only container
Build Service with Docker in 90 minutes6 09/16/16
http://docs.docker.com/userguide/dockervolumes/
Img source from:
http://centricconsulting.com/it-shops-will-leverage-their-knowledge-

7. Exercise 1: Revisit Dockerfile
 Download code
$ git clone https://github.com/larrycai/docker-tomcat
 Build Service
$ vi Dockerfile
$ docker build .
Build Service with Docker in 90 minutes7 09/16/16
code https://github.com/larrycai/docker-tomcat

8. Exercise 2: Manage data in tomcat
 run larrycai/tomcat without volume
$ docker run –P –d larrycai/tomcat
$ docker logs <id>
 Share the local directory into it
$ docker run -v `pwd`:/var/lib/tomcat7/webapps/ -P -d
larrycai/tomcat
$ docker ps
$ docker inspect <id>
 Download sample.war
$curl
https://tomcat.apache.org/tomcat-7.0-doc/appdev/sample/sample.war
> sample.war
 Visit the service
http://192.168.59.103:<port>/sample/
Build Service with Docker in 90 minutes8 09/16/16
code https://github.com/larrycai/docker-tomcat
sample.war https://tomcat.apache.org/tomcat-7.0-doc/appdev/sample/sample.war

9. Exercise 3: Data container for tomcat
1. Create data container (Tips: use –e https_proxy:<proxy>)
$ docker run –v /tmp/webapps:/var/lib/tomcat7/webapps –-name
webfarm jamtur01/fetcher https://tomcat.apache.org/tomcat-
7.0-doc/appdev/sample/sample.war
2. Share data from another container
$ docker run –-volumes-from webfarm –P –d larrycai/tomcat
3. Try to download new one Calendar.war to put into
/tmp/wepapps
Build Service with Docker in 90 minutes9 09/16/16
Code https://github.com/jamtur01/dockerbook-code/blob/master/code/6/tomcat/fetcher/Dockerfile
Calendar.war https://gwt-examples.googlecode.com/files/Calendar.war

10. Link the containers in docker
 Docker container has the same private network
 Name the container and Link them to provide the service
outside and hide internal port/network !
 Name the container
docker run --name postgresql92 postgresql
 Link container to the another container
--link name:alias
docker --link postgresql92:db app
Build Service with Docker in 90 minutes10 09/16/16
http://docs.docker.com/userguide/dockerlinks/ Img source from http://lethain.com/introduction-to-
architecting-systems-for-scale/

11. Exercise 4: Link tomcat with haproxy
 Start tomcat with name web
$ docker run –-name tomcat –d larrycai/tomcat
 Start another node with link alias
$ docker run -it --link tomcat:web
docker.cn/docker/busybox
 Check environment and access it
# env # check environment
# cat /etc/hosts # check host
# wget web:8080
 Create another tomcat and Add HAProxy container
$ docker run –-name tomcat1 –d larrycai/tomcat
$ docker run –-name tomcat2 –d larrycai/tomcat
$ docker run –-link tomcat1:back1 –-link tomcat2:back2 –it –P larrycai/haproxy bash
# export CONFIG=/etc/haproxy/haproxy.cfg
# echo " server back1 ${BACK1_PORT_8080_TCP_ADDR}:8080 maxconn 32" >> $CONFIG
# echo " server back2 ${BACK2_PORT_8080_TCP_ADDR}:8080 maxconn 32" >> $CONFIG
# haproxy -f /etc/haproxy/haproxy.cfg
# ^P^Q
Access mapped 80/8080 port
Build Service with Docker in 90 minutes11 09/16/16

12. Docker in Docker
 Docker is client/Daemon via REMOTE API
 Docker in Docker can make environment much clean
 Docker Host only environment
 All applications are in docker container
 Easy to deployment
 Docker in Docker means install Docker Client into
Container
https://get.docker.io/builds/Linux/x86_64/docker-latest
Build Service with Docker in 90 minutes12 09/16/16

13. Exercise 5: Docker in Docker
 Install docker client in docker container
 Run docker command inside !!
$ docker run –it -v /var/run/docker.sock:/docker.sock larrycai/docker
bash
# docker images
 Point to Docker Host & Pass data inside
# docker –H unix:///docker.sock images
or
# export DOCKER_HOST=unix:///docker.sock
# docker images
Build Service with Docker in 90 minutes13 09/16/16

14. Exercise 6: Build Service Together
 Do it all
 Show the help
 Run the 2 tomcat container & Run the one haproxy container
over it.
 Show the generated port
 $ docker run larrycai/craft
Build Service with Docker in 90 minutes14 09/16/16
Docker HostDocker Host
HAProxy
(Load Balancer)
Tomcat
(web1)
Tomcat
(web1)
808080
8080
Web Service
Tomcat
(web2)
Tomcat
(web2)
8080
ClientClient
Craft
(controll)
https://github.com/larrycai/docker-images/tree/master/craft
/demo.sh/demo.sh

15. Docker Compose
 Compose is a tool for defining and running complex
applications with Docker.
 With Compose, you define a multi-container application
in a single file, then spin your application up in a single
command which does everything that needs to be done
to get it running.
 https://docs.docker.com/compose/
Build Service with Docker in 90 minutes15 09/16/16

16. Install in boot2docker
 Boot2docker can’t install compose locally, But we can
use docker in docker to access it
 Pull image
 $ docker pull dduportal/docker-compose:latest
 Set alias
 alias compose='docker run --rm -ti
-v "$(pwd)":/app
-v /var/run/docker.sock:/var/run/docker.sock
dduportal/docker-compose:latest‘
https://registry.hub.docker.com/u/dduportal/docker-compose/
Build Service with Docker in 90 minutes16 09/16/16

17. Exercise 7(optional): Build Service With Docker
Compose
 Create the compose file
$vi docker-compose.yml
web1:
image: larrycai/tomcat:latest
web2:
image: larrycai/tomcat:latest
proxy:
image: larrycai/haproxy
ports:
- "80:8080"
links:
- web1:back1
- web2:back2
$compose up
Build Service with Docker in 90 minutes17 09/16/16

18. Recommend reading
 The Docker Book
 http://dockerbook.com
 Docker Docs
 https://docs.docker.com/
Build Service with Docker in 90 minutes18 09/16/16