Docker Overview

        docker --help # to list all available options

        docker pull ${image}  # to get image from default docker registry: docker pull nginx
        # Build a image
        docker build -t ${image}:${tag} ./ # if Dockerfile is in the current folder
        docker build -t ${image}:${tag}  -f /path/to/Dockerfile # to specify path or custom file name
        ##  --build-arg bvar_name=value  to argument value if you use ARG in your Dockerfile
        docker history ${image}  # to see image build history

        docker run --name myconten  -i -t myimage /bin/bash
        docker exec -it ${container_name_or_id} bash #or bash or sh according to case# to enter inside container

        docker stop {container_name_or_id} # to stop
        docker start {container_name_or_id}

        docker ps   # to see the running containers
        docker ps -a  # to see all including stopped/crashed containers
        docker ps -f "status=exited" # to see only stopped containers
        is_runned=$(docker ps -q -f "name=${cont_name}")

        docker stop $(docker ps -a -q)  # stop all container
        docker stop $(docker ps -a -q)  # remove all container
        docker rmi $(docker images -q)  #remove all images.

        # Log in a registry

        docker login -u ${registry}

        # commit container changes into new image
        # useful when you manually change/add something
        #inside container and you want to save/keep it for next time
        docker commit - a="auteur" -m="message" {container_name_or_id} ${new_image}

        # copy file between server and container
        docker cp myfile   {container_name_or_id}:/dst/myfile #from server to container
        docker cp {container_name_or_id}:/dst/myfile  //myfile

        docker export containerID > filename.tar  # Export a container’s filesystem as a tar archive
        docker save imageID > filename.tar  # Save one or more images to a tar archive 
        # or like
        docker save -o filename.tarr imageID

        docker load <  filename.tar   # Load an image from a tar archive or STDIN
        docker load --input filename.tar

        docker inspect ${container_name_or_id} # to see container conf details
        docker inspect --format='{{json .State.Health}}' ${container_name_or_id}

        # docker import: Import the contents from a tarball to create a filesystem image
        docker import  filename.tar
        cat filename.tar| docker import - ${new name}

        ## You can also clone an exisitng server filesystem to use it to create image
        ## Example below

        ## You must exclude some system folder like: sys, proc, dev/pts, mnt
        ## Then you can exclude another folders if you want

        cd /mnt

        tar -cvpf fullbackup.tar --directory=/ --exclude=proc --exclude=sys --exclude=dev/pts --exclude=tmp --exclude=backups \
        --exclude=mnt  --exclude=home/osadmin --exclude=lost+found --exclude=images --exclude=media --exclude=users --exclude=opt \
        --exclude=var/log --exclude=var/lib/docker --exclude=var/log/docker  --exclude=usr/tmp --exclude=usr/lib/vmware-tools \
        --exclude=usr/lib/firmware --exclude=usr/share/doc .

        # Import archive as Docker image
        cat fullbackup.tar | docker import - myserverclone:1.0.0

    {
    "insecure-registries" : ["myregistrydomain.com:5000"]
    }

    mkdir –p  /path/newfolder
    chmod 701 /path/to/newfolder
    service docker stop
    # if you already have docker data: images/containers and you want to keep
    ## you can copy /var/li/docker content in the new one like
    sudo rsync -aP /var/lib/docker/  /path/newfolder

        vim /etc/docker/daemon.json # Create if does not exist yet and add this:
            {
            "storage-driver": "overlay2"   ## an already existing key in my case
            ,"data-root": "/path/newfolder"  ##added to change /var/docker/

            }

        # Start a Docker service
        service docker start

        # you can now delete /var/lib/docker

        ## create index.php
        cat > index.php << EOF
        <!DOCTYPE html>
        <html>
        <head>
            <title> Check system </title>
        </head>
        <body>
        <p> Welcome: I am a PHP-APACHE Container! </p>

        <?php
        echo "<h5> System Info </h5>";
        echo " ";
        $unam = shell_exec('uname -a');
        echo "<pre>$unam</pre>";
        $lscpu = shell_exec('lscpu | head -23');
        echo "<pre>$lscpu</pre>";
        ?>

        <?php
        echo "<h5> Load average </h5>";
        echo " ";
        $uptim = shell_exec('uptime');
        echo "<pre>$uptim</pre>";
        echo " "
        ?>

        <?php
        echo "<h5> CPU and MEM </h5>";
        echo " ";
        $cpumem = shell_exec('top -b -n1 | head -3');
        echo "<pre>$cpumem</pre>";
        echo " "
        ?>

        <?php
        echo "<h5> top </h5>";
        echo " ";
        $top = shell_exec('top -b -n1');
        echo "<pre>$top</pre>";
        echo " "
        ?>

        <?php
        echo "<h5> Stockage </h5>";
        echo " ";
        $free = shell_exec('free');
        echo "<pre>$free</pre>";
        $dfh = shell_exec('df -h');
        echo "<pre>$dfh</pre>";
        echo " "
        ?>

        <?php
        echo "<h5> Users list </h5>";
        echo " ";
        $userlist = shell_exec('cut -d: -f1 /etc/passwd');
        echo "<pre>$userlist</pre>";
        echo " "
        ?>

        </body>
        </html>
        EOF

        docker run -d -p 80:80 --name my-app -v "$PWD":/var/www/html php:7.0-apache

        # visit http://localhost or http://${server_ip}
        ```

    tests somme commands:
    docker, info docker images, docker ps; docker ps -a, docker inspect,
    docker run, docker logs, docker stop docker rm, docker volume ls

    [Discover CLI command](https://docs.docker.com/engine/reference/commandline/docker/){:target="_blank"}
    pratical test: https://katacoda.com/alvagante/scenarios/3

    More about [docker run command](https://docs.docker.com/engine/reference/run/#general-form){:target="_blank"}

    Pratical test [HERE](https://katacoda.com/allamand/courses/docker-course/docker-basics){:target="_blank"},

    do **only** from step **1** to step **3** (1, 2 and 3)

    learn dockerfile: https://docs.docker.com/engine/reference/builder/#usage
    Only Step4: katacoda: https://katacoda.com/allamand/courses/docker-course/docker-basics

    Build image in our server(not in katacoda) with Dockerfile

        1. write a simple html file
        2- write a Dockerfile 
                *** use httpd base image to deploy a basic web site: 
             static base image: amp-prod-repo-artifacts.equant.com:5005/orange/httpd-mime:1.0 
         
            ** add or copy your source file in your image: 
        3 build your image

        4 run your container 
          **change  your web site port 8081 
          create a docker volume "myvolume" see docker volume.. 
          using it by mounting the /var/www/html/

    ## run ubuntu container
    image: docker.io/ubuntu:latest

    ## To run 
      docker run --name ubuntu -d docker.io/ubuntu:latest tail -f /dev/null 
     # to enter inside 
     docker exec -it ubuntu bash 
     #the container ubuntu: is equivalent(like) of your machine/vm/server with OS ubuntu 
      
     ## first step: 
       a- enter inside: 
          install apache, deploy a simple html page(index.html) 
          then: install PHP and try to deploy now a dynamique page(index.php) 
           { you can do this directly by skipping html step if you want}
        b: you have finished to deploy all web services in your server ubuntu

    ## second step:
        Now write a Dockerfile to do all manual actions you do above inside container
        to allow another one to have an ready image with theses services

    ## deploy your website with docker run  to test it

    !!! Read only page content, DON'T FOLLOW its sub links

    about docker-compose: https://docs.docker.com/compose/overview/
    command docker-compose: https://docs.docker.com/compose/reference/overview/
    docker-compose file
        version2: https://docs.docker.com/compose/compose-file/compose-file-v2/
        version3: https://docs.docker.com/compose/compose-file/

    Only step5 katacoda: https://katacoda.com/allamand/courses/docker-course/docker-basics

    Write on our server, write docker-compose.yml to deploy you exercice2 website

    FROM docker.io/ubuntu:latest

    LABEL MAINTAINER="xxx" \
        Version="xxx" \
        Name="xxx" \
        Vendor="xxx"

    ## pour le dpkg
    ENV DEBIAN_FRONTEND noninteractive
    USER root

    RUN apt-get update && \
        apt-get install apache2 apache2-doc apache2-utils -y && \
            apt-get install php -y && \
            apt-get install apt-utils -y &&\
            apt-get install vim -y && \
            apt-get install curl -y

    #ajout de conf pour example.conf
    ADD example.com.conf /etc/apache2/sites-available

    RUN echo "Europe/Paris" > /etc/timezone && \
        dpkg-reconfigure -f noninteractive tzdata && \
        a2dissite 000-default.conf && \
        mkdir -p /var/www/example.com/public_html && \
        mkdir /var/www/example.com/logs

    COPY index.php /var/www/example.com/public_html/
    ADD start.sh /tmp/

    RUN a2ensite example.com.conf && \
        chmod 777 /tmp/start.sh
    CMD /tmp/start.sh

    ## start.sh
    #!/bin/bash
    service apache2 start &
    while true
    do
            echo "coucou, je suis toto"
            sleep 1
    done