Class: GithubActions::Container

Inherits:
Object
  • Object
show all
Includes:
Colorizer
Defined in:
lib/tasks/github_actions/github_actions/container.rb

Overview

Manage a Docker container

Constant Summary collapse

TIMEOUT =

the default timeout in seconds, maximum time for the running container, after the time runs out the container is automatically stopped and removed unless ‘KEEP_CONTAINER` option is set

3600
ENV_VARIABLES =

the default environment variables in the container

{
  # this is a CI environment
  "CI"             => "true",
  # skip the modified check in the "rake osc:build" task
  "CHECK_MODIFIED" => "0"
}.freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Colorizer

#error, #info, #stage, #success, #warning

Constructor Details

#initialize(image, options = nil) ⇒ Container

constructor

Parameters:

  • image (String) —

    name of the Docker image to use

  • options (String, nil) (defaults to: nil) —

    extra docker options



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 47

def initialize(image, options = nil)
  @image = image
  @options = options
end

Instance Attribute Details

#container ⇒ Object (readonly)

Returns the value of attribute container.



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 29

def container
  @container
end

#image ⇒ Object (readonly)

Returns the value of attribute image.



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 29

def image
  @image
end

#options ⇒ Object (readonly)

Returns the value of attribute options.



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 29

def options
  @options
end

Instance Method Details

#copy_current_dir ⇒ Object

copy the current directory to the current directory in the container



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 134

def copy_current_dir
  copy_files(Dir.pwd, cwd)
end

#copy_files(from, to) ⇒ Object

copy the files from host into the container

Parameters:

  • from (String) —

    the source path, if it is a directory all content is copied (including subdirectories)

  • to (String) —

    the target location in the container



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 120

def copy_files(from, to)
  stage("Copying #{from} to #{to} in the container...")

  if File.directory?(from)
    # Dir.children is similar to Dir.entries but it omits the "." and ".." values
    Dir.children(from).each do |f|
      system("docker cp #{f.shellescape} #{container.shellescape}:#{to.shellescape}")
    end
  else
    system("docker cp #{from.shellescape} #{container.shellescape}:#{to.shellescape}")
  end
end

#cwd ⇒ String

get the current working directory in the container

Returns:

  • (String) —

    the path



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 112

def cwd
  `docker exec #{container.shellescape} pwd`.chomp
end

#pull ⇒ Object

pull the Docker image, ensure that the latest version is used



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 53

def pull
  stage("Pulling the #{image} image...")
  # if the latest image is already present it does nothing
  system("docker pull #{image.shellescape}")
end

#run(cmd, env = {}) ⇒ Boolean

run a command in the container, runs “docker exec” the command is executed in a shell, so shell metacharacters like “&&” can be used to join several commands

Parameters:

  • cmd (String) —

    the command to run, it is passed to a shell to it might contain multiple commands or shell meta characters

  • env (Hash) (defaults to: {}) —

    optional environment variables (with mapping “name” => “value”)

Returns:

  • (Boolean) —

    ‘true` if the command succeeded (exit status 0), `false` otherwise



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 103

def run(cmd, env = {})
  stage("Running command: #{cmd}")
  system("docker exec -it #{env_options(env)} #{container.shellescape} " \
    "sh -c #{cmd.shellescape}")
  $CHILD_STATUS.success?
end

#start ⇒ Object

start the container, runs “docker create” and “docker start”



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 60

def start
  stage("Starting the container...")

  # define the initial command for the container to start
  if keep_container?
    # running "tail -f /dev/null" does nothing and gets stuck forever,
    # this ensures the container keeps running and we can execute
    # the other commands there via "docker exec"
    run = "tail"
    args = "-f /dev/null"
  else
    # the "sleep" command ensures the container shuts down automatically after
    # the timeout (to abort frozen jobs or avoid hanging containers after a crash)
    run = "sleep"
    args = TIMEOUT
  end

  cmd = "docker create #{env_options(ENV_VARIABLES)} --rm --entrypoint " \
    "#{run} #{options} #{ENV["DOCKER_OPTIONS"]} #{image.shellescape} #{args}"

  # contains the container ID
  @container = `#{cmd}`.chomp
  system("docker start #{container.shellescape} > /dev/null")
end

#stop ⇒ Object

stop and remove the container from the system, runs “docker rm”



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# File 'lib/tasks/github_actions/github_actions/container.rb', line 86

def stop
  if keep_container?
    print_container_usage
  else
    stage("Stopping the container...")
    system("docker rm --force #{container.shellescape} > /dev/null")
  end
end