docker-nodejs

NodeJS.require(Docker)

NodeJS Meetup Thessaloniki, June 2016

TheodorosPloumis.com / @theoploumis

Get them: online presentation / source code / docker image / video

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Let me ask you

• Who knows about Docker?
• Who uses Docker for development?
• Who uses Docker in production?
• Who tried but could not do it?

What is Docker

Docker is an open platform for developing, shipping, and running applications.

See more on the Docker introduction slides

Docker vs VMs

Docker Benefits

• Fast (deployment, migration, restarts)
• Secure
• Lightweight (save disk & CPU)
• Open Source
• Portability
• Microservices and integrations (APIs)
• Simplify DevOps
• Version control capabilities
• Docker: 1-process-per-container && NodeJS: single-process

Technology behind Docker

• Linux x86-64
• Go language
• Client- Server (deamon) architecture
• Union file systems (UnionFS: AUFS, btrfs, vfs etc)
• Namespaces (pid, net, ipc, mnt, uts)
• Control Groups (cgroups)
• Container format (libcontainer)

See more at Understanding docker

Steps of a Docker workflow

docker run -i -t ubuntu /bin/bash

• Pulls the ubuntu image from the registry
• Creates a new CONTAINER_ID
• Allocates a filesystem and mounts a read-write layer
• Allocates a network/bridge interface
• Sets up an IP address
• Executes a process that you specify (/bin/bash)
• Captures and provides application output

The Docker terminology

• (docker) engine
• client
• machine
• image
• container
• compose
• swarm
• distribution

Docker flow diagram

Agenda

• Try NodeJS* apps
• The docker hub
• Public Dockerfiles
• Explore docker cli
• Dockerizing NodeJS
• Using Docker with NodeJS

Try NodeJS* apps and software

// Try mean.io stack. Open localhost:8010
docker pull gbevan/meanio
docker run -d -p 8010:3000 --name meanio gbevan/meanio

// Try Nagios. Open localhost:8120/nagios (user: nagiosadmin pass: admin)
docker pull quantumobject/docker-nagios
docker run -d -p 8125:25 -p 8120:80 --name nagios quantumobject/docker-nagios

// Try Wekan. Open localhost:8040
docker pull mongo
docker pull mquandalle/wekan
docker run -d --name wekan-db mongo
docker run -d --link "wekan-db:db" \
           -e "MONGO_URL=mongodb://db" -p 8040:80 mquandalle/wekan

Topics: run, link, ports, containers

The docker hub

• hub.docker.com
• page of readytalk/nodejs
• REST API v1
• REST API v2
• images of readytalk/nodejs, v1
• info about tplcom namespace. v2
• Let's upload theodorosploumis/php-chat to the hub

Topics: hub, registry, public images

Public Dockerfiles

Popular Dockerfiles from hub.docker.com

• A list of NodeJS public images
• node/0.10.45
• node/slim
• jprjr/tinynode
• shawnzhu/ruby-nodejs
• scratch
• nodesource explicit images

Documented Dockerfile reference.

Topics: basics, images, Dockerfile, hub

Explore docker cli commands

// General info
man docker // man docker-run
docker help // docker help run
docker info
docker version
docker network ls

// Images
docker images // docker [IMAGE_NAME]
docker pull [IMAGE] // docker push [IMAGE]

// Containers
docker run ...
docker exec ...
docker ps // docker ps -a, docker ps -l
docker stop/start/restart [CONTAINER_ID]
docker stats [CONTAINER_ID]
docker top [CONTAINER_ID]
docker port [CONTAINER_ID]
docker inspect [CONTAINER_ID]
docker inspect -f "{{ .State.StartedAt }}" [CONTAINER_ID]
docker rm [CONTAINER_ID]

Topics: dry, wharfee, docker simple ui, cli

Dockerizing NodeJS

FROM nodesource/jessie:0.12.13

# Set the NodeJS environment to dev (vs production)
ENV NODE_ENV dev

# cache package.json and node_modules to speed up builds
ADD package.json /package.json
RUN npm install

# Add your local files to the image
ADD . /path/to/app

# Setup the workdir
WORKDIR /path/to/app

# Optional volume the app
VOLUME /path/to/app

# Expose ports
EXPOSE 3000

CMD ["npm","start"]

Other basic examples: 1.

Topics: npm, cache layers

Using Docker with NodeJS

A simple NodeJS app with redis.

git clone git@github.com:thess-docker/docker-scale-node.git
cd docker-scale-node

docker-compose up -d
...

docker-compose run web env
docker-compose logs
docker-compose stop
docker-compose restart
docker-compose down
docker-compose up redis

Other useful examples 1, 2, 3, 4

Topics: docker-compose, ci, testing

Docker tips

There are known best practices (get a list at examples/tips)

• Optimize containers (check fromlatest.io)
• Create your own tiny base
• Containers are not Virtual Machines
• Full stack Images vs 1 process per Container
• Create your private registry
• Create shortcut commands
• Volume database and code source to save state

Docker NodeJS specific tips

• Keep the dependencies out of your app (npm_modules)
• Think of (micro)services and roles
• Use start scripts for containers with executable
• Use data only containers and share volumes
• Keep images small and version-specific
• In .dockerignore exclude .git, .gitignore, node_modules/
• Prefer ENTRYPOINT ["npm", "start"]

Docker tools for NodeJS

npm with/for Docker

• dockerode
• dockunit
• docker node tester, dnt
• generator-docker

The Docker ecosystem grows exponentially.

Instead of Resources

• Join beta.docker.com now!
• Subscribe to the official Newsletter
• Awesome Docker (list of Docker resources & projects)
• Docker cheat sheet
• Docker in Practice, The Docker Book (books)
• Docker aliases/shortcuts
• Docker introduction presentation

Questions

you.send('Feedback');

Tools used: oh my zsh, reveal.js, Simple Docker UI for Chrome, wharfee, dry, docker compose 1.7.1, docker 1.11.1.

Wait, Bonus!

SKGTech.io has a docker image and a docker-compose.yml file now.