Module: Poise::Utils

Extended by:
Utils
Included in:
Utils
Defined in:
lib/poise/utils.rb,
lib/poise/utils/shell_out.rb,
lib/poise/utils/resource_provider_mixin.rb

Defined Under Namespace

Modules: ResourceProviderMixin, ShellOut

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.ancestor_send(obj, msg, *args, default: nil, ignore: [default]) ⇒ Object

Try to find an ancestor to call a method on.

Examples:

val = @val || Poise::Utils.ancestor_send(self, :val)

Parameters:

  • obj (Object) —

    Self from the caller.

  • msg (Symbol) —

    Method to try to call.

  • args (Array<Object>) —

    Method arguments.

  • default (Object) (defaults to: nil) —

    Default return value if no valid ancestor exists.

  • ignore (Array<Object>) (defaults to: [default]) —

    Return value to ignore when scanning ancesors.

Returns:

  • (Object)

Since:

  • 2.2.3

  • 2.3.0 Added ignore parameter.



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# File 'lib/poise/utils.rb', line 83

def ancestor_send(obj, msg, *args, default: nil, ignore: [default])
  # Class is a subclass of Module, if we get something else use its class.
  obj = obj.class unless obj.is_a?(Module)
  ancestors = []
  if obj.respond_to?(:superclass)
    # Check the superclass first if present.
    ancestors << obj.superclass
  end
  # Make sure we don't check obj itself.
  ancestors.concat(obj.ancestors.drop(1))
  ancestors.each do |mod|
    if mod.respond_to?(msg)
      val = mod.send(msg, *args)
      # If we get the default back, assume we should keep trying.
      return val unless ignore.include?(val)
    end
  end
  # Nothing valid found, use the default.
  default
end

.find_cookbook_name(run_context, filename) ⇒ String

Find the cookbook name for a given filename. The can used to find the cookbook that corresponds to a caller of a file.

Examples:

def my_thing
  caller_filename = caller.first.split(':').first
  cookbook = Poise::Utils.find_cookbook_name(run_context, caller_filename)
  # ...
end

Parameters:

  • run_context (Chef::RunContext) —

    Context to check.

  • filename (String) —

    Absolute filename to check for.

Returns:

  • (String)

Raises:



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# File 'lib/poise/utils.rb', line 39

def find_cookbook_name(run_context, filename)
  possibles = {}
  Poise.debug("[Poise] Checking cookbook for #{filename.inspect}")
  run_context.cookbook_collection.each do |name, ver|
    # This special method is added by Halite::Gem#as_cookbook_version.
    if ver.respond_to?(:halite_root)
      # The join is there because ../poise-ruby/lib starts with ../poise so
      # we want a trailing /.
      if filename.start_with?(File.join(ver.halite_root, ''))
        Poise.debug("[Poise] Found matching halite_root in #{name}: #{ver.halite_root.inspect}")
        possibles[ver.halite_root] = name
      end
    else
      Chef::CookbookVersion::COOKBOOK_SEGMENTS.each do |seg|
        ver.segment_filenames(seg).each do |file|
          # Put this behind an environment variable because it is verbose
          # even for normal debugging-level output.
          Poise.debug("[Poise] Checking #{seg} in #{name}: #{file.inspect}")
          if file == filename
            Poise.debug("[Poise] Found matching #{seg} in #{name}: #{file.inspect}")
            possibles[file] = name
          end
        end
      end
    end
  end
  raise Poise::Error.new("Unable to find cookbook for file #{filename.inspect}") if possibles.empty?
  # Sort the items by matching path length, pick the name attached to the longest.
  possibles.sort_by{|key, value| key.length }.last[1]
end

.parameterized_module(mod, &block)

This method returns an undefined value.

Create a helper to invoke a module with some parameters.

Examples:

module MyMixin
  def self.my_mixin_name(name)
    # ...
  end
end

Poise::Utils.parameterized_module(MyMixin) do |name|
  my_mixin_name(name)
end

Parameters:

  • mod (Module) —

    The module to wrap.

  • block (Proc) —

    The module to implement to parameterization.

Raises:

Since:

  • 2.3.0



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# File 'lib/poise/utils.rb', line 120

def parameterized_module(mod, &block)
  raise Poise::Error.new("Cannot parameterize an anonymous module") unless mod.name && !mod.name.empty?
  parent_name_parts = mod.name.split(/::/)
  # Grab the last piece which will be the method name.
  mod_name = parent_name_parts.pop
  # Find the enclosing module or class object.
  parent = parent_name_parts.inject(Object) {|memo, name| memo.const_get(name) }
  # Object is a special case since we need #define_method instead.
  method_type = if parent == Object
    :define_method
  else
    :define_singleton_method
  end
  # Scoping hack.
  self_ = self
  # Construct the method.
  parent.send(method_type, mod_name) do |*args|
    self_.send(:check_block_arity!, block, args)
    # Create a new anonymous module to be returned from the method.
    Module.new do
      # Fake the name.
      define_singleton_method(:name) do
        super() || mod.name
      end

      # When the stub module gets included, activate our behaviors.
      define_singleton_method(:included) do |klass|
        super(klass)
        klass.send(:include, mod)
        klass.instance_exec(*args, &block)
      end
    end
  end
end

Instance Method Details

#ancestor_send(obj, msg, *args, default: nil, ignore: [default]) ⇒ Object

Try to find an ancestor to call a method on.

Examples:

val = @val || Poise::Utils.ancestor_send(self, :val)

Parameters:

  • obj (Object) —

    Self from the caller.

  • msg (Symbol) —

    Method to try to call.

  • args (Array<Object>) —

    Method arguments.

  • default (Object) (defaults to: nil) —

    Default return value if no valid ancestor exists.

  • ignore (Array<Object>) (defaults to: [default]) —

    Return value to ignore when scanning ancesors.

Returns:

  • (Object)

Since:

  • 2.2.3

  • 2.3.0 Added ignore parameter.



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# File 'lib/poise/utils.rb', line 83

def ancestor_send(obj, msg, *args, default: nil, ignore: [default])
  # Class is a subclass of Module, if we get something else use its class.
  obj = obj.class unless obj.is_a?(Module)
  ancestors = []
  if obj.respond_to?(:superclass)
    # Check the superclass first if present.
    ancestors << obj.superclass
  end
  # Make sure we don't check obj itself.
  ancestors.concat(obj.ancestors.drop(1))
  ancestors.each do |mod|
    if mod.respond_to?(msg)
      val = mod.send(msg, *args)
      # If we get the default back, assume we should keep trying.
      return val unless ignore.include?(val)
    end
  end
  # Nothing valid found, use the default.
  default
end

#find_cookbook_name(run_context, filename) ⇒ String

Find the cookbook name for a given filename. The can used to find the cookbook that corresponds to a caller of a file.

Examples:

def my_thing
  caller_filename = caller.first.split(':').first
  cookbook = Poise::Utils.find_cookbook_name(run_context, caller_filename)
  # ...
end

Parameters:

  • run_context (Chef::RunContext) —

    Context to check.

  • filename (String) —

    Absolute filename to check for.

Returns:

  • (String)

Raises:



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# File 'lib/poise/utils.rb', line 39

def find_cookbook_name(run_context, filename)
  possibles = {}
  Poise.debug("[Poise] Checking cookbook for #{filename.inspect}")
  run_context.cookbook_collection.each do |name, ver|
    # This special method is added by Halite::Gem#as_cookbook_version.
    if ver.respond_to?(:halite_root)
      # The join is there because ../poise-ruby/lib starts with ../poise so
      # we want a trailing /.
      if filename.start_with?(File.join(ver.halite_root, ''))
        Poise.debug("[Poise] Found matching halite_root in #{name}: #{ver.halite_root.inspect}")
        possibles[ver.halite_root] = name
      end
    else
      Chef::CookbookVersion::COOKBOOK_SEGMENTS.each do |seg|
        ver.segment_filenames(seg).each do |file|
          # Put this behind an environment variable because it is verbose
          # even for normal debugging-level output.
          Poise.debug("[Poise] Checking #{seg} in #{name}: #{file.inspect}")
          if file == filename
            Poise.debug("[Poise] Found matching #{seg} in #{name}: #{file.inspect}")
            possibles[file] = name
          end
        end
      end
    end
  end
  raise Poise::Error.new("Unable to find cookbook for file #{filename.inspect}") if possibles.empty?
  # Sort the items by matching path length, pick the name attached to the longest.
  possibles.sort_by{|key, value| key.length }.last[1]
end

#parameterized_module(mod, &block)

This method returns an undefined value.

Create a helper to invoke a module with some parameters.

Examples:

module MyMixin
  def self.my_mixin_name(name)
    # ...
  end
end

Poise::Utils.parameterized_module(MyMixin) do |name|
  my_mixin_name(name)
end

Parameters:

  • mod (Module) —

    The module to wrap.

  • block (Proc) —

    The module to implement to parameterization.

Raises:

Since:

  • 2.3.0



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# File 'lib/poise/utils.rb', line 120

def parameterized_module(mod, &block)
  raise Poise::Error.new("Cannot parameterize an anonymous module") unless mod.name && !mod.name.empty?
  parent_name_parts = mod.name.split(/::/)
  # Grab the last piece which will be the method name.
  mod_name = parent_name_parts.pop
  # Find the enclosing module or class object.
  parent = parent_name_parts.inject(Object) {|memo, name| memo.const_get(name) }
  # Object is a special case since we need #define_method instead.
  method_type = if parent == Object
    :define_method
  else
    :define_singleton_method
  end
  # Scoping hack.
  self_ = self
  # Construct the method.
  parent.send(method_type, mod_name) do |*args|
    self_.send(:check_block_arity!, block, args)
    # Create a new anonymous module to be returned from the method.
    Module.new do
      # Fake the name.
      define_singleton_method(:name) do
        super() || mod.name
      end

      # When the stub module gets included, activate our behaviors.
      define_singleton_method(:included) do |klass|
        super(klass)
        klass.send(:include, mod)
        klass.instance_exec(*args, &block)
      end
    end
  end
end