Overview

Concept For Docker
- Docker Image - Images are read-only templates containing instructions for creating a container. A Docker image creates containers to run on the Docker platform.
- Docker Container - A container is an isolated environment where an application runs without affecting the rest of the system and without the system impacting the application.
- Existing Container - When the user starts up a Docker image as a container, the container will be called “Existing Container“ and you can find it on “docker ps“.
- Stop Docker Container - Docker container cannot be removed until it stops, it can be stopped via “docker stop [container]“ or “exit for pseudo tty mode“.
- Exited / Stopped Container - The exited/stopped container will NOT show in the “docker ps“ command, but stores in “docker ps -a“.
- Remove Docker Container - The container ONLY allows removal after stops.

START Docker Container

EXPLAIN How To START Docker Container

# Create and run a new container from an image
# It has a lot of flags and options can be set up when docker run.
# docker run [OPTIONS] IMAGE [COMMAND] [ARG...]
# Options
# -i, --interactive     Keep STDIN open even if not attached
# --name        Assign a name to the container
# --privileged      Give extended privileges to this container
# -p, --publish     Publish a container's port(s) to the host
# -t, --tty     Allocate a pseudo-TTY
# -u, --user        Username or UID (format: <name|uid>[:<group|gid>])
# -v, --volume      Bind mount a volume


# Run a container with root privileged and enable tty
e.g.
$ docker run --privileged -it -u jenkins_agent -p 4723:4723 -p 10022:22 -v /dev/bus/usb:/dev/bus/usb --name test test-ubuntu:0.33

# Run a container with root privileged and execute command when starts
e.g.
$ docker run --privileged -d -p 4723:4723 -v /dev/bus/usb:/dev/bus/usb --name test test-ubuntu:0.33 appium -a 172.17.0.2 -p 4723 --allow-cors --session-override --relaxed-security --log-timestamp --local-timezone

START Docker Container

SET Docker's apt Repository

# Add Docker's official GPG key:
$ sudo apt update
$ sudo apt install ca-certificates curl
$ sudo install -m 0755 -d /etc/apt/keyrings
$ sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
$ sudo chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository to Apt sources:
# If you posted this command failed, tried get it from docker tutorial.
$ echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
$ sudo apt update

Install The Docker Engine

SET Docker's apt Repository

# Add Docker's official GPG key:
$ sudo apt update
$ sudo apt install ca-certificates curl
$ sudo install -m 0755 -d /etc/apt/keyrings
$ sudo curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc
$ sudo chmod a+r /etc/apt/keyrings/docker.asc

# Add the repository to Apt sources:
# If you posted this command failed, tried get it from docker tutorial.
$ echo \
  "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu \
  $(. /etc/os-release && echo "$VERSION_CODENAME") stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
$ sudo apt update

INSTALL The Docker Packages

$ sudo apt install docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin

ADD User To Docker Group

$ sudo usermod -aG docker [$USER]
# re-login user to activate

VERIFY The Docker Engine Has Been Installed

$ sudo docker run hello-world
...
Hello from Docker!
This message shows that your installation appears to be working correctly.
...

Frequently Used Docker Commands

EXECUTE A Command In A Running Container

# This command runs a new command in a running container, it only runs while the container's primary process (PID 1) is running.
$ docker exec [options] [container name] [command]
e.g.
$ docker exec -it [CONTAINER ID] bash

FETCH The Logs Of A Container

# The docker logs command batch-retrieves logs present at the time of execution.
$ docker logs [container name]

LIST Existing And Exited/Stopped Docker Containers

# List Existing Docker Containers
$ docker ps
CONTAINER ID   IMAGE     COMMAND   CREATED   STATUS    PORTS     NAMES
...

# List All Docker Containers
$ docker ps -a
CONTAINER ID   IMAGE                                COMMAND                  CREATED       STATUS                     PORTS     NAMES
4189dc7e795c   test-ubuntu:0.33                     "/bin/bash"              2 weeks ago   Exited (129) 2 weeks ago             test
282d0759f1bb   jenkins/agent:latest-jdk17           "java -jar /usr/shar¡K"   2 weeks ago   Exited (1) 2 weeks ago               agent
97a305060cf1   jxpower/appium-server:latest-arm64   "bash"                   3 weeks ago   Exited (129) 3 weeks ago             appium
6ae3c160405b   ubuntu:jammy-20240627.1              "/bin/bash"              4 weeks ago   Exited (255) 3 weeks ago             ubuntu
...

SET Volume

# Set volume option when creating container
# -v, --volume      Bind mount a volume
$ docker run -v [/local/dir]:[/target/container/dir]

SET Port

# Set port option when creating container
# -p, --publish     Publish a container's port(s) to the host
# -P, --publish-all     Publish all exposed ports to random ports in host

# docker run -p [/local/port]:[/container/port]
$ docker run -p 4723:4723 -p 10022:22

# With the -P flag, you can automatically publish all exposed ports to ephemeral ports.
# This is quite useful when you’re trying to avoid port conflicts in development or testing environments.
# docker run -P [/local/port]:[/container/port]
$ docker run -P

START A Exited/Stopped Docker Container

# When the docker container has been run but exited, and you want to re-launch it
$ docker start [container name]

STOP A Running Docker Container

# When we want to stop a running docker container
$ docker stop [container name]

REMOVE Docker Images

# Remove one or more images
$ docker rmi [Image Name]

REMOVE Exited/Stopped Docker Container

# Remove Exited / Stopped Docker Container
# The existing conatainer is Unremovable, you need to stop container first.
# rm [Container Name / Container ID], the "Container Name" can be found in "docker ps -a" command, if the container doesn't has name, the conatiner id is acceptable
$ docker rm [Container Name / Container ID]

# Remove all Stopped Containers at once
$ docker rm $(docker ps -aq --filter  status="exited")

RENAME Docker Container

# Renames the given container to new_name
$ docker rename [container] [new_name]

RUN Docker Container With Interactive And Bash

# -i, --interactive    Keep STDIN open even if not attached
# --name,    Assign a name to the container
# -t, --tty    Allocate a pseudo-TTY
# [IMAGE REPOSITORY], [TAG], and [IMAGE ID] can be found in "docker images" command
# the "bash" tells which shell run for TTY
$ docker run --name [name you like] -it [IMAGE REPOSITORY:TAG] bash
or
$ docker run --name [name you like] -it [IMAGE ID] bash

Build Dockerfile

BUILD A Custom Docker Image

Type this command to build the file into a docker image.
# Before build docker image, you need create a file and put command into it. (refer Custome Dockerfile Example)
$ sudo vim [dockerfile name]

# When the file is ready, type the following command to transfer it to docker image
# -f, --file [/path/to/Dockerfile]    Name of the Dockerfile (default: PATH/Dockerfile)
# --no-cache    Do not use cache when building the image
# -t, --tag [REPOSITORY]:[TAG]    Name and optionally a tag (format: name:tag)
$ docker build -f [/path/to/Dockerfile] [--no-cache] -t [REPOSITORY]:[TAG] .
e.g.
$ docker build -f Dockerfile_ubuntu --no-cache -t test-ubuntu:0.33 .

Custom Dockerfile Example

The following example is NOT recommended to take place in an actual scenario, I made it for running automation on docker but it has too many limitations.
It installed Python, Robot Framework, Appium, and other packages and ran on Ubuntu.
•   It’s “NOT“ a good idea to install sudo on Docker
•   Keep the Dockerfile simplify
FROM ubuntu:jammy-20240627.1

# Image info
LABEL description='A Robot Framework+Appium for CI in RPI ububtu' author='Victor.Chang'

# SET environment variables
ENV DEBIAN_FRONTEND=noninteractive
ENV TZ=Asia/Taipei
ARG USER=jenkins_agent
ARG HOME_DIR=/home/$USER
EXPOSE 4723 5037 22

# CHANGE root password
RUN echo 'root:********' | chpasswd
# CREATE new account: jenkins_agent with password and groups
RUN useradd -m -s /bin/bash $USER
RUN echo $USER':********' | chpasswd
RUN usermod -aG root,dialout,sudo,plugdev $USER


# UPDATE to the latest
RUN apt update && apt upgrade -y
# INSTALL essential packages
# NOT recommended using sudo in docker
RUN apt install -y ssh
RUN apt install -y tzdata usbutils vim file

## INSTALL Appium relevant packages
## Including Node.js, NPM, android-sdk, adb and fastboot
RUN apt install -y curl
RUN curl -fsSL https://deb.nodesource.com/setup_20.x | bash
RUN apt install -y nodejs
# RUN apt install build-essential -y
RUN apt install -y android-sdk android-tools-adb android-tools-fastboot
RUN npm install -g appium
RUN echo 'export ANDROID_HOME=/usr/lib/android-sdk' >> ~/.bashrc
RUN echo 'export PATH=$PATH:$ANDROID_HOME/tools' >> ~/.bashrc
RUN echo 'export PATH=$PATH:$ANDROID_HOME/platform-tools' >> ~/.bashrc

# INSTALL Python3.12
RUN apt install -y software-properties-common
RUN add-apt-repository ppa:deadsnakes/ppa -y
RUN apt update
RUN apt install -y python3.12
# RUN echo 'export PATH=$PATH:/usr/bin/python3.12' >> ~/.bashrc
# SET python3.12 settings
RUN echo 'alias python=python3.12' >> ~/.bashrc
# RUN source ~/.bashrc
# Installing pip3
RUN curl -sS https://bootstrap.pypa.io/get-pip.py | python3.12
RUN echo 'export PATH=/home/$USER/.local/bin:$PATH' >> ~/.bashrc

# DOWNLOAD automation codes from git
RUN apt install -y git

# Add jenkins_agent into groups
RUN usermod -aG plugdev,dialout,root,$USER $USER

#
RUN cp /root/.bashrc /home/$USER/.bashrc
RUN cp /root/.profile /home/$USER/.profile

##
# Install Jenkins packages
##

# CHANGE user to jenkins_agent
USER $USER
WORKDIR $HOME_DIR
RUN appium driver install uiautomator2

Build Docker Compose

To Be Added

Build Docker Compose

Install Docker Engine on Ubuntu
- https://docs.docker.com/engine/install/ubuntu/
Docker Images Commands List
- https://www.runoob.com/docker/docker-images-command.html
Docker buildx build
- https://docs.docker.com/reference/cli/docker/buildx/build/
Docker container run
- https://docs.docker.com/reference/cli/docker/container/run/

Install/Run Docker On Linux

Overview

START Docker Container

EXPLAIN How To START Docker Container

START Docker Container

SET Docker's apt Repository

Install The Docker Engine

SET Docker's apt Repository

INSTALL The Docker Packages

ADD User To Docker Group

VERIFY The Docker Engine Has Been Installed

Frequently Used Docker Commands

EXECUTE A Command In A Running Container

FETCH The Logs Of A Container

LIST Existing And Exited/Stopped Docker Containers

SET Volume

SET Port

START A Exited/Stopped Docker Container

STOP A Running Docker Container

REMOVE Docker Images

REMOVE Exited/Stopped Docker Container

RENAME Docker Container

RUN Docker Container With Interactive And Bash

Build Dockerfile

BUILD A Custom Docker Image

Custom Dockerfile Example

Build Docker Compose

Build Docker Compose

Victor.Chang

你可能感興趣的文章

留言討論

Install/Run Docker On Linux

Overview

START Docker Container

EXPLAIN How To START Docker Container

START Docker Container

SET Docker's apt Repository

Install The Docker Engine

SET Docker's apt Repository

INSTALL The Docker Packages

ADD User To Docker Group

VERIFY The Docker Engine Has Been Installed

Frequently Used Docker Commands

EXECUTE A Command In A Running Container

FETCH The Logs Of A Container

LIST Existing And Exited/Stopped Docker Containers

SET Volume

SET Port

START A Exited/Stopped Docker Container

STOP A Running Docker Container

REMOVE Docker Images

REMOVE Exited/Stopped Docker Container

RENAME Docker Container

RUN Docker Container With Interactive And Bash

Build Dockerfile

BUILD A Custom Docker Image

Custom Dockerfile Example

Build Docker Compose

Build Docker Compose

Victor.Chang

你可能感興趣的文章

Take a Ten Minutes Walk

PHP 與 MySQL 的互動：讀取、新增、刪除、編輯資料

test

留言討論