learning:with Thomas @ Search Investment Group

Slides & codes: http://bit.ly/thomasdocker

Ref: 8 surprising facts about real docker adoption

Ref: Docker Customers, StackShare

Virtual Machines Docker

Benefits● Lightweight

● Experiment and use whatever technology fits best

● Having multiple versions of tools without crashing (Java, Python 2 & 3, etc)

● Automated deployment

● Quickly and accurately set up environments for DEV, UAT, etc.

● Scale easily

Today’s Demo

● Install Docker

● Download and run a Hello World Docker image

● Compose our own Hello World Docker Image

● Compose our own Docker Image that contains a PHP-MySQL application

Install Docker (MacOS)

https://www.docker.com/products/

Install Docker (Windows)

Hello World

Hello-world container

Docker Store

Find the Image

Hello World$ docker --versionDocker version 1.13.0, build 49bf474

$ docker pull hello-worldUsing default tag: latest

latest: Pulling from library/hello-world

78445dd45222: Pull complete

Digest: sha256:c5515758d4c5e1e838e9cd307f6c6a0d620b5e07e6f927b07d05f6d12a1ac8d7

$ docker run hello-worldHello from Docker!

(...)

Ref for our “SSL Deep Inspection”:Docker behind proxy that changes ssl certificate

Basic Docker Commands$ docker images(list the images you pulled)

$ docker ps(list the running containers)

$ docker ps -a(list all containers, including exited)

$ docker [command] --help(check the documentation)

$ docker rmi [image ID](remove the image by the associated ID

- you don’t have to type in full ID!)

$ docker stop [container ID](stop the running container by the ID)

$ docker rm [container ID](stop and remove the container from the

ps -a list)

$ docker ps -aq | xargs docker rm(stop and remove all containers)

Build our own Hello World

Python container

Our hello-world container

Hello World in Python$ echo 'print("Hello from Thomas")' > app.py

$ cat app.py

print("Hello from Thomas")

$ python app.py

Hello from Thomas

Docker Store

Dockerfile & docker-compose.yml$ vi Dockerfile

FROM python

MAINTAINER Thomas Tong <hello@thomastong.me>

COPY app.py app.py

CMD python app.py

$ vi docker-compose.yml

helloworld:

build: .

Describes the necessary steps to build the container

Describes the container in its running state (environment variables, dependencies to others containers, etc)

Ref: Docker Compose vs. Dockerfile

Compose a Docker Image$ ls

Dockerfile app.py

docker-compose.yml

$ docker-compose build

Building helloworld

Step 1/4 : FROM python

latest: Pulling from library/python

5040bd298390: Pull complete

fce5728aad85: Pull complete

76610ec20bf5: Pull complete

52f3db4b5710: Pull complete

45b2a7e03e44: Pull complete

75ef15b2048b: Pull complete

e41da2f0bac3: Pull complete

Digest:

sha256:cba517218b4342514e000557e6e9100018f980cda866420

ff61bfa9628ced1dc

Status: Downloaded newer image for python:latest

---> 775dae9b960e

Step 2/4 : MAINTAINER Thomas Tong

<hello@thomastong.me>

---> Running in b257c26e3b5e

---> b6a9ca588053

Removing intermediate container b257c26e3b5e

Step 3/4 : COPY app.py app.py

---> c30eb29c8920

Removing intermediate container 5c74e320839d

Step 4/4 : CMD python app.py

---> Running in 5c2295d819ad

---> b54de6654b62

Removing intermediate container 5c2295d819ad

Successfully built b54de6654b62

Run the Docker Image$ docker images

REPOSITORY TAG IMAGE ID CREATED SIZE

2helloworld_helloworld latest b54de6654b62 7 minutes ago 687 MB

python latest 775dae9b960e 7 minutes ago 687 MB

$ docker run [image name/ID]

Hello from Thomas

$ docker-compose up

Creating 2helloworld_helloworld_1

Attaching to 2helloworld_helloworld_1

helloworld_1 | Hello from Thomas

2helloworld_helloworld_1 exited with code 0

You can only use this after building the image

Build and start according to the Dockerfile and docker-compose.yml, good for development

Apache httpd + PHP + MySQL

PHP httpd

Our site

MySQL

Sample App - Feed Moby Dock

Credits: Originally done in Flask by acloud.guru, rewritten in PHP

Feed button and fed count

Random message from database

Docker Store

Docker Store

Docker Store

“latest” tag is used by default

Our Files$ ls -R

Dockerfile docker-compose.yml

./cert:

server.crt server.csr server.key

./conf:

000-default.conf apache2.conf default-ssl.conf php.ini

./database:

seed.sql

./public:

(...)

Docker image config files

HTTPS Cert

Apache and PHP config files

SQL to create DB

Our Web App files

DockerfileFROM php:apache

RUN docker-php-ext-install mysqliCOPY conf/php.ini /usr/local/etc/php/

RUN a2enmod headersRUN a2enmod rewriteRUN a2enmod ssl

COPY cert/server.crt /etc/ssl/certs/COPY cert/server.key /etc/ssl/certs/

COPY conf/000-default.conf /etc/apache2/sites-enabled/COPY conf/default-ssl.conf /etc/apache2/sites-enabled/COPY conf/apache2.conf /etc/apache2/

COPY public/ /var/www/html/COPY .env /var/www/html/

Found in Docker Store PHP image’s description

Run apache commands to set up additional modules

Copy php.ini from image to container’s file system

Ref: Docker Command CMD vs RUN, COPY vs ADD

Copy SSL cert and httpd config files

Copy Web App files

docker-compose.ymlexample_app_db: image: mysql environment: MYSQL_ROOT_PASSWORD: ${MYSQL_ROOT_PASSWORD} MYSQL_DATABASE: ${MYSQL_DATABASE} MYSQL_USER: ${MYSQL_USER} MYSQL_PASSWORD: ${MYSQL_PASSWORD} ports: - '3306:3306' volumes: - ~/.docker-volumes/exampleapp/mysql/data:/var/lib/mysql - ./database/seed.sql:/docker-entrypoint-initdb.d/seed.sql

example_app: build: . links: - example_app_db ports: - '80:80' - '443:443'

Variables found in MySQL image descriptionUse MySQL image

Link with MySQL image defined above

Map HTTP and HTTPS ports (local port:container port)

Map local volume to container volume and seed SQL file to init directory

Read .env file with ${VAR_NAME}

Map local port 3306 to container

Build and Run$ vi .env

MYSQL_ROOT_PASSWORD=password

MYSQL_DATABASE=exampleapp

MYSQL_USER=exampleapp

MYSQL_PASSWORD=password

$ docker-compose up

(...)

$ docker ps

CONTAINER ID IMAGE PORTS

bda700bcf1ab 3phpapp_example_app 0.0.0.0:80->80/tcp, 0.0.0.0:443->443/tcp

cf443ee159e7 mysql 0.0.0.0:3306->3306/tcp

Setting up environments with different configs, you may:

● create multiple docker-compose.yml files● create multiple .env files and use reference

Check port mappings here

Docker Inspect$ docker inspect [container ID]

(...)

"Env": [

"MYSQL_ROOT_PASSWORD=password",

"MYSQL_PASSWORD=password",

"MYSQL_USER=exampleapp",

"MYSQL_DATABASE=exampleapp",

(...)

$ docker exec -it [container ID] sh

#

Check whether environment variables are loaded correctly

Run bash shell in a container to check its file system

Check Seed Database# mysql -u root -p

mysql> show databases;

+--------------------+

| Database |

+--------------------+

| information_schema |

| exampleapp |

| mysql |

| performance_schema |

| sys |

+--------------------+

5 rows in set (0.02 sec)

mysql> use exampleapp

mysql> show tables;

+----------------------+

| Tables_in_exampleapp |

+----------------------+

| Feed |

| Messages |

+----------------------+

2 rows in set (0.00 sec)

mysql> select * from Messages;

+----------------------------------------------+

| message |

+----------------------------------------------+

| Thanks good sir. I am feeling quite healthy! |

| Thanks for the meal buddy. |

| Please stop feeding me. I am getting huge! |

+----------------------------------------------+

3 rows in set (0.00 sec)

Try it in https://localhost/

Click the button and hear from Moby Dock

If you want to redo this exercise, don’t forget to remove database files from your local machine (hint: check the yml)

What have we Achieved?

● Learnt the skills○ To download and use Docker images○ To compose our own Docker image

● Learnt the benefits○ Lightweight○ Experiment and use whatever technology fits best○ Having multiple versions of tools without crashing (Java, Python 2 & 3, etc)○ Automated deployment○ Quickly and accurately set up environments for development, UAT, etc.○ Scale easily

Scale easily? Really?

...or Actually the Same?

● What to do when adding new machines?

● How do containers discover each other?

● What happens if containers die?

● What if the host machine is down?

● What happens if 1 container is using excessive resources?

#GIFEE● GIFEE - Google Infrastructure for Everyone Else● Google starts over 2 billion containers per week● Container Orchestration● Docker Swarm, Kubernetes● Cluster as a giant computer

Modern DevOps Architecture

Git Push Git Hook

Git / Source Ctrl. Jenkins / Continuous Integration Server

Static Tests

Unit TestsReporting

Docker Compose

Build

Docker Orchestration Docker Registry

Store

Docker Pull

...and they lived happily ever after.

Further Watchings & Readings● Docker for DevOps - From Development to Production

MOOC by acloud.guru

● Scalable Microservices with KubernetesMOOC by Google and Udacity

● Shipping code with Docker + Kubernetes (Cantonese)Recordings of 20 Jun 2016 Meetup @ OneSky

● ...and remember not to overkill: It’s the Future, It really is the futureBlog by CircleCI

learning:with Thomas @ Search Investment Group

Slides & codes: http://bit.ly/thomasdocker