NodeJS.require(Docker)

NodeJS Meetup Thessaloniki, June 2016

---

TheodorosPloumis.com / @theoploumis

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

Share under CC BY 4.0

---

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.