minimal_docker_app

Simple app with a complete easy-guide for docker TODO: networks (docker<->docker, docker<->vps, docker<->world)

DOCKER GUIDE

PART 1 - INSTALLATION

Installation: In ubuntu 16.04:

sudo apt-get update
sudo apt-key adv --keyserver hkp://p80.pool.sks-keyservers.net:80 --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
sudo apt-add-repository 'deb https://apt.dockerproject.org/repo ubuntu-xenial main'
sudo apt-get update
apt-cache policy docker-engine

Output:

docker-engine:
Installed: (none)
Candidate: 17.05.0~ce-0~ubuntu-xenial (version could change)
...

Then...

sudo apt-get install -y docker-engine
sudo systemctl status docker

Output:

docker.service - Docker Application Container Engine
Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled)
Active: active (running) since Sun 2018-08-19 13:35:15 UTC; 24s ago
...

After that...

control+C
sudo docker info

Output:

Containers: 0
Running: 0
Paused: 0
Stopped: 0
Images: 0
Server Version: 17.05.0-ce
...

Testing:

sudo docker run hello-world

Output:

Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
9db2ca6ccae0: Pull complete
Digest: sha256:4b8ff392a12ed9ea17784bd3c9a8b1fa3299cac44aca35a85c90c5e3c7afacdc
Status: Downloaded newer image for hello-world:latest

Hello from Docker!
This message shows that your installation appears to be working correctly.
...

sudo docker image ls

Output:

REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
hello-world         latest              2cb0d9787c4d        5 weeks ago         1.85kB

sudo docker container ls --all

Output:

CONTAINER ID        IMAGE               COMMAND             CREATED              STATUS                          PORTS               NAMES
5b71cee88939        hello-world         "/hello"            About a minute ago   Exited (0) About a minute ago                       relaxed_bhabha

Cheatsheet (from docker docs):

## List Docker CLI commands
    docker
    docker container --help

## Display Docker version and info
    docker --version
    docker version
    docker info

## Execute Docker image
    docker run hello-world

## List Docker images
    docker image ls
    docker images

## List Docker containers (running, all, all in quiet mode)
    docker container ls
    docker container ls --all
    docker container ls -aq

PART 2 - SETTING UP

Creating a Dockerfile:

Dockerfile: (Set of rules/actions/configurations in a container/image)

# Use a Python runtime as a parent image
FROM frolvlad/alpine-python3

# Set metadata about the maintainer of the image
LABEL maintainer="Urbano Gutierrez <urbano@fatwhale.io>"

# Set the working directory to /app
WORKDIR /app

# Copy the current directory contents into the container at /app
ADD . /app

# Update the system
RUN apk update && apk upgrade && \
    apk add --no-cache \
    bash \
    git \
    openssh \
    build-base \
    make \
    python3-dev

# Install any needed packages specified in requirements.txt
RUN pip install --upgrade pip
RUN pip install -r requirements.txt

# Run main.py when the container is ready
CMD ["python", "-u", "main.py"]

Building the container/image:

With our application inside a folder ex: (project_1)

You have few ways to have this project here, clonning it from github, uploading using sftp or ftp ...

cd project_1
ls project_1

Output:

Dockerfile  main.py  Readme.md  requirements.txt

docker build -t atagfortheproject .

Output:

Sending build context to Docker daemon  5.632kB
Step 1/7 : FROM frolvlad/alpine-python3
latest: Pulling from frolvlad/alpine-python3
8e3ba11ec2a2: Pull complete
83d8aa72cb9b: Pull complete
Digest: sha256:8d9f2a8e577acac8cc1f6633dbd7731fa764a14e6905e93d8deac2895fe0ceff
Status: Downloaded newer image for frolvlad/alpine-python3:latest
---> a056c2d555fe
Step 2/7 : LABEL maintainer "Urbano Gutierrez <@urbiGT>"
---> Running in 8bcccc02ca05
---> 98a0c6f5e85b
Removing intermediate container 8bcccc02ca05
Step 3/7 : WORKDIR /app
---> 38586ee4b707
Removing intermediate container f8445b53b9cf
Step 4/7 : ADD . ./app
---> 6f21c6071c75
Removing intermediate container 0aaf3d89e959
Step 5/7 : RUN apk update && apk upgrade &&     apk add --no-cache     bash     git     openssh     build-base     make     python3-dev
---> Running in 6a00f7e2c8ea
fetch http://dl-cdn.alpinelinux.org/alpine/v3.8/main/x86_64/APKINDEX.tar.gz
...
Removing intermediate container 2c68a17cec27
Step 8/8 : CMD python main.py
---> Running in 903ab59926bd
---> 6a51ac14aba4
Removing intermediate container 903ab59926bd
Successfully built 6a51ac14aba4
Successfully tagged projectapp:latest

used projectapp as tag, numbers/ids changes

---OPTIONAL TO HAVE ACCESS FROM OTHER MACHINES---

Log-in docker:

register on https://hub.docker.com/

create a repository ex: test-app (set it as private)

sudo docker login

Output:

Login with your Docker ID to push and pull images from Docker Hub. If you don't have a Docker ID, head over to https://hub.docker.com to create one.
Username: your-username
Password:
Login Succeeded

Check the image ID:

sudo docker images

Output:

    REPOSITORY              TAG       IMAGE ID         CREATED           SIZE
    yourcontainername     latest    yourimageID     3 minutes ago     1.975 GB
    ...

Push image to docker:

sudo docker tag yourimageID yourusername/testapp:yourversiontag
sudo docker push yourusername/testapp

Output:

    The push refers to a repository [docker.io/urbanon/testapp]
    874792b6ae85: Pushed
    471984be847f: Pushed
    b367ab4e7128: Pushed
    5a70acc82f16: Pushed
    af57e8fffa65: Pushed
    f4c48043d646: Mounted from frolvlad/alpine-python3
    73046094a9b8: Mounted from frolvlad/alpine-python3
    yourversiontag: digest: sha256:777bdec7f6d3f2c3d21301bc7c98d3c0c9d661d93b56daf0512721b9e5cc65bf size: 1787

used yourversiontag as tag, 6a51ac14aba4 as IMAGEID

care, this uses a lot of bandwidth

Download a image:

after using sudo docker login in another vps

sudo docker pull yourusername/yourappname:yourversiontag

Output:

yourversiontag: Pulling from urbanon/testapp
Digest: sha256:777bdec7f6d3f2c3d21301bc7c98d3c0c9d661d93b56daf0512721b9e5cc65bf
Status: Image is up to date for urbanon/testapp:yourversiontag

used yourversiontag as tag, testapp as app name, urbanon as account, same VPS (Status: Image is up to date... not downloaded)

PART 3 - RUNNING

Run a image:

sudo docker run -d urbanon/testapp:yourversiontag

Get logs:

sudo docker logs containerID

Output:

  `Heey, it should be working`

urbanonymous/minimal_docker_app

minimal_docker_app

DOCKER GUIDE

PART 1 - INSTALLATION

PART 2 - SETTING UP

PART 3 - RUNNING