Class: Airbrussh::Rake::Context

Inherits:
Object
  • Object
show all
Defined in:
lib/airbrussh/rake/context.rb

Overview

Maintains information about what Rake task is currently being invoked, in order to be able to decorate SSHKit commands with additional context-sensitive information. Works via a monkey patch to Rake::Task, which can be disabled via by setting Airbrussh.configuration.monkey_patch_rake = false.

Note that this class is not thread-safe. Normally this is not a problem, but some Capistrano users are known to use ‘invoke` to switch the Rake task in the middle of an SSHKit thread, which causes Context to get very confused. It such scenarios Context is not reliable and may return `nil` for the `position` of a command.

Defined Under Namespace

Modules: Patch

Class Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(config = Airbrussh.configuration) ⇒ Context

Returns a new instance of Context.



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# File 'lib/airbrussh/rake/context.rb', line 20

def initialize(config=Airbrussh.configuration)
  @history = []
  @enabled = config.monkey_patch_rake
  self.class.install_monkey_patch if enabled?
end

Class Attribute Details

.current_task_name ⇒ Object

Returns the value of attribute current_task_name.



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# File 'lib/airbrussh/rake/context.rb', line 17

def current_task_name
  @current_task_name
end

Class Method Details

.install_monkey_patch ⇒ Object 



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# File 'lib/airbrussh/rake/context.rb', line 62

def self.install_monkey_patch
  require "rake"
  return if ::Rake::Task.include?(::Airbrussh::Rake::Context::Patch)

  ::Rake::Task.prepend(::Airbrussh::Rake::Context::Patch)
end

Instance Method Details

#current_task_name ⇒ Object

Returns the name of the currently-executing rake task, if it can be determined. If monkey patching is disabled, this will be nil.



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# File 'lib/airbrussh/rake/context.rb', line 28

def current_task_name
  return nil unless enabled?
  self.class.current_task_name
end

#position(command) ⇒ Object

The zero-based position of the specified command in the current rake task. May be ‘nil` in certain multi-threaded scenarios, so be careful!



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# File 'lib/airbrussh/rake/context.rb', line 50

def position(command)
  history.index(command.to_s)
end

#register_new_command(command) ⇒ Object

Update the context when a new command starts by:

  • Clearing the command history if the rake task has changed

  • Recording the command in the history

Returns whether or not this command was the first execution of this command in the current rake task



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# File 'lib/airbrussh/rake/context.rb', line 39

def register_new_command(command)
  reset_history_if_task_changed

  first_execution = !history.include?(command.to_s)
  history << command.to_s
  history.uniq!
  first_execution
end