Purpose

I want to build the latest environment as much as possible at the minimum.

Prerequisites

Development environment

macOS Catalina(ver. 10.15.7)
Docker Desktop(ver. 3.03)
Docker(ver. 20.10.0)

Refusal

――It is an environment constructed on a trial basis. ――For various reasons, one container has multiple roles. --Even if it is "#" at the time of actual execution, it is written with "$". --I wrote the password directly, because it is a trial environment.

Implementation

Creating a base image

Creating a directory

$ mkdir -p containers/base_image
$ cd containers/base_image

Dockerfile description

Write a Dockerfile.

$ vi Dockerfile

Enable systemd by referring to Docker Hub description. Migrated from CentOS 8 to CentOS Stream by referring to Official information of CentOS Stream.

[Dockerfile]

FROM centos:latest
MAINTAINER tora_tz

ENV CONTAINER_NAME local/cos-stream
ENV CONTAINER_VERSION 20210104_01

#Migrate to Centos Stream
#Install CentOS Stream repository information
RUN dnf install -y centos-release-stream

#Delete repository information
RUN dnf swap -y centos-{linux,stream}-repos

#Synchronize with the latest package
RUN dnf distro-sync -y

Run image build

#Build
$ docker build --rm -t local/cos-stream .
#Confirm that it was built
$ docker images
REPOSITORY         TAG       IMAGE ID       CREATED          SIZE
local/cos-stream   latest    f0ccd16bd6fc   16 seconds ago   526MB

Create a base image for development

Create a minimum image required for development that contains Ruby.

Creating a Dockerfile

First of all, confirmation with the minimum contents

$ mkdir ../dev_base
$ cd ../dev_base
$ vi Dockerfile

[Dockerfile]

FROM local/cos-stream
MAINTAINER tora_tz

# system update
RUN dnf -y upgrade; dnf clean all;

Run image build

$ docker build --rm -t local/dev_base:0.1 .
(Omission)
Successfully tagged local/dev_base:0.1
$ docker images
REPOSITORY         TAG       IMAGE ID       CREATED          SIZE
local/dev_base     0.1       cab625bee967   10 seconds ago   532MB
local/cos-stream   latest    f0ccd16bd6fc   10 minutes ago   526MB

Create a container

#Create and start.
$ docker run -dit --name dev_base_container local/dev_base:0.1
#Check the created container.
$ docker ps
CONTAINER ID   IMAGE                COMMAND       CREATED         STATUS         PORTS     NAMES
ae0b8ebe78b2   local/dev_base:0.1   "/bin/bash"   5 seconds ago   Up 5 seconds             dev_base_container

After that, when starting up, do as follows.

$ docker start dev_base_container

Check what is included by default

#Go inside the container
$ docker exec -it dev_base_container bash

#Confirm that you have migrated to CentOS Stream.

$ cat /etc/centos-release
CentOS Stream release 8

#Check what is in
$ dnf list installed

When deleting

$ docker stop dev_base_container
$ docker rm dev_base_container

I rewrote the Dockerfile as follows. Specifically, the following points have been fixed.

--Install rbenv for Ruby version control. --Install nodenv for version control of Node.js. --Added environment variables so that you can check the version of the container from the inside.

FROM local/cos-stream
MAINTAINER tora_tz
ENV CONTAINER_VERSION 0.2

# system update&install
RUN dnf -y upgrade && dnf install -y git && dnf clean all

# anyenv install
SHELL ["/bin/bash", "-c"]
RUN git clone https://github.com/anyenv/anyenv ~/.anyenv
ENV PATH ~/.anyenv/bin:$PATH
RUN echo 'eval "$(anyenv init -)"' >> ~/.bash_profile
RUN anyenv install --force-init
RUN anyenv install rbenv
RUN anyenv install nodenv
RUN exec $SHELL -l

Check if the path of rbenv and node nv is in the path

#Build
$ docker run -dit --name dev_base_container local/dev_base:0.2
# --Without login,.bash_profile doesn't work.
$ docker exec -it dev_base_container /bin/bash --login
$ rbenv install --list
2.5.8
2.6.6
2.7.2
3.0.0
$ nodenv install --list
(Omission)
15.2.1
15.3.0
15.4.0
15.5.0

Make sure you have Ruby 3.0.

Corrected Dockerfile by referring to Dependent library at build time.

[Dockerfile]


FROM local/cos-stream
MAINTAINER tora_tz

ENV CONTAINER_NAME dev_name
ENV CONTAINER_VERSION 0.3

# change bash
SHELL ["/bin/bash", "-c"]

# system update&install
RUN dnf upgrade -y \ 
  && dnf install -y dnf-plugins-core \
  && dnf config-manager  --enable powertools \
  && dnf install -y sudo which git gcc make bzip2 openssl-devel libyaml-devel libffi-devel readline-devel zlib-devel gdbm-devel ncurses-devel \
  && dnf clean all

ENV DOCKER_USER developer
RUN useradd -mU ${DOCKER_USER}
#Add sudo settings
RUN echo '${DOCKER_USER} ALL=(ALL:ALL) ALL' | EDITOR='tee -a' visudo
# RUN echo '${DOCKER_USER}    ALL=(ALL)      NOPASSWD:ALL' >> /etc/sudoers
#Grant sudo privileges
RUN gpasswd -a ${DOCKER_USER} ${DOCKER_USER}
#Belong to a sudo-enabled group.
RUN usermod -aG wheel ${DOCKER_USER}
#Set password
RUN echo "${DOCKER_USER}:dev_pass" | chpasswd
#Change execution user
USER ${DOCKER_USER}
ENV WORKSPACE_PATH /home/${DOCKER_USER}/workspace
RUN mkdir -p ${WORKSPACE_PATH}
WORKDIR ${WORKSPACE_PATH}

# anyenv install
RUN git clone https://github.com/anyenv/anyenv ~/.anyenv
ENV PATH ~/.anyenv/bin:$PATH
RUN echo 'eval "$(anyenv init -)"' >> ~/.bashrc
RUN anyenv install --force-init
RUN anyenv install rbenv
RUN anyenv install nodenv
RUN exec $SHELL -l

# Ruby&Node.js Install
RUN source ~/.bashrc \ 
  && rbenv install 3.0.0 \
  && rbenv global 3.0.0 \
  && nodenv install 15.5.0 \
  && nodenv global 15.5.0

Creating an image / starting a container

$ docker build --rm -t local/dev_base:0.3 .
$ docker stop dev_base_container
$ docker rm dev_base_container
$ docker run -dit --name dev_base_container local/dev_base:0.3
$ docker exec -it dev_base_container /bin/bash --login
$ ruby -v
ruby 3.0.0p0 (2020-12-25 revision 95aff21468) [x86_64-linux]
$ node -v
v15.5.0
$ gem -v
3.2.3
$ bundler -v
Bundler version 2.2.4

Creating a base image for Rails development

Creating a Dockerfile

$ mkdir ../dev_rails_base
$ cd ../dev_rails_base
$ vi Dockerfile

[Dockerfile]

FROM local/dev_base:0.3
MAINTAINER tora_tz
ENV CONTAINER_NAME dev_rails_base
ENV CONTAINER_VERSION 0.1
USER ${DOCKER_USER}
ENV APP_ROOT ${WORKSPACE_PATH}/rails_test
RUN mkdir -p ${WORKSPACE_PATH}/rails_test
WORKDIR ${APP_ROOT}
USER root
#Add the yarn repository and install the Rails dependent libraries.
# see https://classic.yarnpkg.com/ja/docs/install/#centos-stable
RUN curl --silent --location https://dl.yarnpkg.com/rpm/yarn.repo | tee /etc/yum.repos.d/yarn.repo && dnf install -y yarn sqlite gcc-c++
#Set up the repository using the MariaDB package repository setup script.
# see https://mariadb.com/kb/en/yum/
RUN curl -sS https://downloads.mariadb.com/MariaDB/mariadb_repo_setup | bash
#Install MariaDB
RUN dnf upgrade -y && dnf install -y MariaDB-server galera-4 MariaDB-client MariaDB-shared MariaDB-backup MariaDB-common MariaDB-devel && dnf clean all

USER ${DOCKER_USER}
#Add a Gemfile.
COPY --chown=${DOCKER_USER}:${DOCKER_USER} Gemfile ${APP_ROOT}

#Generate a Gem file.
RUN source ~/.bashrc \
  && bundle config set path 'vendor/bundle' \
  && bundle install \
  && bundle exec rails new  . --force -d mysql --minimal

COPY --chown=${DOCKER_USER}:${DOCKER_USER} database.yml ${APP_ROOT}/config/database.yml

EXPOSE 3000

Gem file fix

$ vi Gemfile

[Gemfile]

# frozen_string_literal: true

source "https://rubygems.org"

git_source(:github) {|repo_name| "https://github.com/#{repo_name}" }

gem "rails", '>= 6.1'

Modify DB connection configuration file

$ vi database.yml

[database.yml]

# MySQL. Versions 5.5.8 and up are supported.
#
# Install the MySQL driver
#   gem install mysql2
#
# Ensure the MySQL gem is defined in your Gemfile
#   gem 'mysql2'
#
# And be sure to use new-style password hashing:
#   https://dev.mysql.com/doc/refman/5.7/en/password-hashing.html
#
default: &default
  adapter: mysql2
  encoding: utf8mb4
  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
  username: rails_user
  password: test_password
  host: localhost

development:
  <<: *default
  database: rails_test_development
  port: 3315

# Warning: The database defined as "test" will be erased and
# re-generated from your development database when you run "rake".
# Do not set this db to the same as development or production.
test:
  <<: *default
  database: rails_test_test

# As with config/credentials.yml, you never want to store sensitive information,
# like your database password, in your source code. If your source code is
# ever seen by anyone, they now have access to your database.
#
# Instead, provide the password or a full connection URL as an environment
# variable when you boot the app. For example:
#
#   DATABASE_URL="mysql2://myuser:mypass@localhost/somedatabase"
#
# If the connection URL is provided in the special DATABASE_URL environment
# variable, Rails will automatically merge its configuration values on top of
# the values provided in this file. Alternatively, you can specify a connection
# URL environment variable explicitly:
#
#   production:
#     url: <%= ENV['MY_APP_DATABASE_URL'] %>
#
# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
# for a full overview on how database connection configuration can be specified.
#
production:
  <<: *default
  database: rails_test_production
  username: rails_test
  password: <%= ENV['RAILS_TEST_DATABASE_PASSWORD'] %>

Creating an image / starting a container

$ docker build --rm -t local/dev_rails_base:0.1 .
$ docker run -dit --name dev_rails_base_container -p49152:3000 local/dev_rails_base:0.1
$ docker exec -it dev_rails_base_container /bin/bash --login
#Launch MariaDB
$ echo dev_pass | sudo -S nohup mysqld_safe &

Execute the following in another tab.

#MariaDB initial setup
$ docker exec -it dev_rails_base_container /bin/bash --login
$ sudo mysql_secure_installation
Enter current password for root (enter for none):test_password
Switch to unix_socket authentication [Y/n]:n
Change the root password? [Y/n]:n
Remove anonymous users? [Y/n]:Y
Disallow root login remotely? [Y/n]:Y
Remove test database and access to it? [Y/n]:Y
Reload privilege tables now? [Y/n]:Y
Thanks for using MariaDB!
$ sudo mysql -u root -p
MariaDB [(none)]> use mysql;
MariaDB [mysql]> SELECT user, host, plugin FROM user;
+-------------+-----------+-----------------------+
| User        | Host      | plugin                |
+-------------+-----------+-----------------------+
| mariadb.sys | localhost | mysql_native_password |
| root        | localhost | mysql_native_password |
| mysql       | localhost | mysql_native_password |
+-------------+-----------+-----------------------+

#Create a user to access from Rails.
MariaDB [mysql]> CREATE USER 'rails_user'@'%' identified by 'test_password';
MariaDB [mysql]> GRANT ALL PRIVILEGES ON *.* TO 'rails_user'@'%' WITH GRANT OPTION;
MariaDB [mysql]> SELECT user, host, plugin FROM user;
+-------------+-----------+-----------------------+
| User        | Host      | plugin                |
+-------------+-----------+-----------------------+
|(Omission)　　　　 |           |                       |
| rails_user  | %         | mysql_native_password |
+-------------+-----------+-----------------------+

MariaDB [mysql]> flush privileges;
MariaDB [mysql]> quit;
$ bin/rails db:create
Created database 'rails_test_development'
Created database 'rails_test_test'
#Start Rails.
$ bin/rails s -b 0.0.0.0

Access to the Rails environment launched in the container

I was able to build it so far.

Future tasks

--Enable systemd. (It seems that you have to have privileges, so give up in some cases)

I tried it for the time being, but at the time of build

[OK]Started Update UTMP about System Runlevel Changes.

Since it stops at, it is necessary to investigate this area when implementing it.

--Switch to Docker Compose and split the container. --Allow development from Visual Studio Code. ――Automate the manual setup. --Enable MariaDB autostart settings. (Since systemctl cannot be used, use mysqld_safe ... but it is necessary to consider the startup time, so countermeasures are required) --Allow DB access from clients such as Sequel Ace. (I tried to add the port setting, but I could not do it, so I need to investigate) --Linkage with GitHub (account is passed as an argument) --Allow information such as a solid password to be passed as an argument from the outside. --You don't have to specify a login shell. (Use ENTRY POINT, etc ...)

Other references

-I wrote CentOS (Docker image) in Japanese environment with Dockerfile -CentOS Official Repository -List of Dockerfile notations that you might use often -How to delete Docker image and container -Check CMD of existing image -About Dockerfile (Japanese translation) -Run Dockerfile RUN and CMD in Bash login shell -Virtualize development environment with Docker

A memorandum when building an environment with Ruby3.0 x Rails6.1 x Docker x CentOS Stream

Purpose

Prerequisites

Development environment

Refusal

Implementation

Creating a base image

Creating a directory

Dockerfile description

Run image build

Create a base image for development

Creating a Dockerfile

Run image build

Create a container

Check what is included by default

Check if the path of rbenv and node nv is in the path

Creating an image / starting a container

Creating a base image for Rails development

Creating a Dockerfile

Gem file fix

Modify DB connection configuration file

Creating an image / starting a container

Access to the Rails environment launched in the container

Future tasks

Other references