Capistrano::Dockerbuild

Capistrano tasks for docker build on remote server.

These tasks depends on Git. And so remote server must have git command.

Installation

Add this line to your application's Gemfile:

gem 'capistrano-dockerbuild'

And then execute:

$ bundle

Or install it yourself as:

$ gem install capistrano-dockerbuild

Usage

Add require and install_plugin to Capfile.

require 'capistrano/dockerbuild'
install_plugin Capistrano::Dockerbuild

Variables

Common Variables

Use common variables

• repo_url
• branch

name	required	default	desc
docker_build_server_host	yes	nil	Build server hostname or SSH::Host object
docker_build_base_dir	yes	nil	Repository clone to here, and execute build command here
docker_registry	no	nil	Docker registry hostname. if use DockerHub, keep nil
docker_build_cmd	no	-> { [:docker, "build", "-t", fetch(:docker_tag_full), "."] }	Execute command for image building
docker_repository_name	no	-> { fetch(:application) }	Use by docker tag {{docker_repository_name}}:tag
docker_tag	no	-> { fetch(:branch) }	Use by docker tag repository:{{docker_tag}}
docker_tag_full	no	-> { #{fetch(:docker_repository_name)}:#{fetch(:docker_tag)}" }	Use by docker tag {{docker_tag_full}}
docker_remote_repository_name	no	-> { fetch(:docker_repository_name) }	Use by docker push docker_registry/{{docker_remote_repository_name}}:docker_remote_tag
docker_remote_tag	no	-> { fetch(:docker_tag) }	Use by docker push docker_registry/docker_remote_repository_name:{{docker_remote_tag}}
docker_remote_tag_full	no	-> { "#{fetch(:docker_registry) &.+ "/"}#{fetch(:docker_remote_repository_name)}:#{fetch(:docker_remote_tag)}" }	Use by docker push {{docker_remote_tag_full}}
keep_docker_image_count	no	10
git_http_username	no	nil	See below
git_http_password	no	nil	See below

If you want to use GitHub Apps installation access token or something to authorize repository access using HTTPS protocol. You can set variables in your config/deploy.rb:

set :git_http_username, -> { ENV["GIT_HTTP_USERNAME"] }
set :git_http_password, -> { ENV["GIT_HTTP_PASSWORD"] }
set :repo_url, -> do
  if fetch(:git_http_username) && fetch(:git_http_password)
    "https://github.com/owner/repo.git"
  else
    "git@github.com:owner/repo.git"
  end
end

Update remote URL always if you set proper value to all of repo_url, git_http_username, and git_http_password.

Tasks

docker:check

• Ensure #{docker_build_base_dir}
• Ensure git reachable

docker:clone

• Clone repo to #{docker_build_base_dir} as mirror

docker:update_mirror

• git remote update #{docker_build_base_dir}

docker:build

• Create #{branch} worktree to #{docker_tag}-#{timestamp}
• With in worktree dir, execute #{docker_build_cmd}
• Clear worktree

docker:push

• docker tag #{docker_tag_full} #{docker_remote_tag_full}
• docker push #{docker_remote_tag_full}

docker:cleanup_local_images

• Remove docker images
• Leave keep_docker_image_count images
• Remove from the oldest image

Task Dependency

docker:push => docker:build => docker:update_mirror => docker:clone => docker:check

Development

After checking out the repo, run bin/setup to install dependencies. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/reproio/capistrano-dockerbuild.

License

The gem is available as open source under the terms of the MIT License.