Class: Dockistrano::Docker

Inherits:
Object
  • Object
show all
Defined in:
lib/dockistrano/docker.rb

Overview

Class for communication with Docker. Uses two means of communication:

  • Actions on containers are executed by calling the docker binary with an ip address of the Docker location. The docker command line client is best capable of executing the actions for building images, running containers and managing containers.

  • Queries are executed using the HTTP API of docker. This API is exposed via HTTP and returns JSON. This allows us to easily parse and return the information.

This class uses two environment variables:

DOCKER_BINARY  - Location of the docker binary on your system
DOCKER_HOST_IP - IP address or host of the docker server

Defined Under Namespace

Classes: EnvironmentVariableMissing, ImageNotFound, ResourceNotFound

Class Method Summary collapse

Class Method Details

.attach(id) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 94

def self.attach(id)
  execute(["attach", id], :stream)
end

.build(full_image_name) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 78

def self.build(full_image_name)
  execute(["build", { t: full_image_name }, "."], :stream)
end

.clean ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 98

def self.clean
  Dockistrano::CommandLine.command_with_stream("#{docker_command} rmi $(#{docker_command} images -a | grep \"^<none>\" | awk '{print $3}')")
  Dockistrano::CommandLine.command_with_stream("#{docker_command} rm $(#{docker_command} ps -a -q)")
end

.console(full_image_name, options = {}) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 68

def self.console(full_image_name, options={})
  options["t"] = true
  options["i"] = true
  if (command = options.delete(:command))
    execute(["run", options, full_image_name, command], :interaction)
  else
    execute(["run", options, full_image_name], :interaction)
  end
end

.docker_command ⇒ Object

Returns the docker command as a string: ‘docker -H 127.0.0.1’

Raises:



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# File 'lib/dockistrano/docker.rb', line 26

def self.docker_command
  raise EnvironmentVariableMissing.new("Missing DOCKER_BINARY in environment, please provide the location of the docker binary") unless ENV["DOCKER_BINARY"]
  raise EnvironmentVariableMissing.new("Missing DOCKER_HOST_IP in environment, please provide the host or ip address of the docker server") unless ENV["DOCKER_HOST_IP"]
  "#{ENV['DOCKER_BINARY']} -H #{ENV['DOCKER_HOST_IP']}"
end

.exec(full_image_name, options = {}) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 60

def self.exec(full_image_name, options={})
  if (command = options.delete(:command))
    execute(["run", options, full_image_name, command], :stream)
  else
    execute(["run", options, full_image_name], :stream)
  end
end

.execute(command, mode = :string_result) ⇒ Object

Executes the given command on the command line



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# File 'lib/dockistrano/docker.rb', line 33

def self.execute(command, mode=:string_result)
  case mode
  when :string_result
    Dockistrano::CommandLine.command_with_result("#{docker_command} #{command.collect { |c| c.kind_of?(String) ? c : arguments(c) }.join(" ")}".strip)
  when :stream
    Dockistrano::CommandLine.command_with_stream("#{docker_command} #{command.collect { |c| c.kind_of?(String) ? c : arguments(c) }.join(" ")}".strip)
  else
    Dockistrano::CommandLine.command_with_interaction("#{docker_command} #{command.collect { |c| c.kind_of?(String) ? c : arguments(c) }.join(" ")}".strip)
  end
end

.image_id(full_image_name) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 118

def self.image_id(full_image_name)
  inspect_image(full_image_name)["id"]
end

.inspect_container(id) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 131

def self.inspect_container(id)
  request(["containers", id, "json"])
end

.inspect_image(full_image_name) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 125

def self.inspect_image(full_image_name)
  response = request(["images", full_image_name, "json"])
rescue ResourceNotFound => e
  raise ImageNotFound.new(e.message)
end

.last_run_container_id(full_image_name) ⇒ Object

Returns the id of the last container with an error



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# File 'lib/dockistrano/docker.rb', line 111

def self.last_run_container_id(full_image_name)
  request(["containers", "json?all=1"]).each do |container|
    return container["Id"] if container["Image"] == full_image_name and container["Command"] != "cat /dockistrano.yml"
  end
  nil
end

.logs(id) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 90

def self.logs(id)
  execute(["logs", id], :stream)
end

.ps(options = {}) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 44

def self.ps(options={})
  execute(["ps", options])
end

.pull(full_image_name, tag) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 82

def self.pull(full_image_name, tag)
  execute(["pull", { t: tag }, full_image_name])
end

.push(image_name, tag) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 86

def self.push(image_name, tag)
  execute(["push", image_name, tag], :stream)
end

.run(full_image_name, options = {}) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 52

def self.run(full_image_name, options={})
  if (command = options.delete(:command))
    execute(["run", options, full_image_name, command])
  else
    execute(["run", options, full_image_name])
  end
end

.running_container_id(full_image_name) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 103

def self.running_container_id(full_image_name)
  request(["containers", "json"]).each do |container|
    return container["Id"] if container["Image"] == full_image_name
  end
  nil
end

.stop(id) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 48

def self.stop(id)
  execute(["stop", id])
end

.stop_all_containers_from_image(full_image_name) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 135

def self.stop_all_containers_from_image(full_image_name)
  containers = request(["containers", "json"])
  containers.each do |container|
    execute(["stop", container["Id"]]) if container["Image"] == full_image_name
  end
end

.tags_for_image(image_name) ⇒ Object 



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# File 'lib/dockistrano/docker.rb', line 142

def self.tags_for_image(image_name)
  images = request(["images", "json"])
  [].tap do |tags|
    images.each do |image|
      tags << image["Tag"] if image["Repository"] == image_name
    end
  end
end