Module: CZTop::Config::Traversing

Included in:
CZTop::Config
Defined in:
lib/cztop/config/traversing.rb

Overview

Methods used to traverse a CZTop::Config tree.

Defined Under Namespace

Classes: ChildrenAccessor, FamilyAccessor, SiblingsAccessor

Instance Method Summary collapse

Instance Method Details

#children ⇒ ChildrenAccessor

Access to this config item’s direct children.

Returns:



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# File 'lib/cztop/config/traversing.rb', line 52

def children
  ChildrenAccessor.new(self)
end

#execute {|config, level| ... } ⇒ Object

Calls the given block once for each CZTop::Config item in the tree, starting with self.

Yield Parameters:

  • config (Config) —

    the config item

  • level (Integer) —

    level of the item (self has level 0, its direct children have level 1)

Returns:

  • (Object) —

    the block’s return value

Raises:

  • (ArgumentError) —

    if no block given

  • (Exception) —

    the block’s exception, in case it raises (it won’t call the block any more after that)



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# File 'lib/cztop/config/traversing.rb', line 16

def execute
  raise ArgumentError, 'no block given' unless block_given?

  exception                           = nil
  block_value                         = nil
  ret                                 = nil
  callback                            = CZMQ::FFI::Zconfig.fct do |zconfig, _arg, level|
    begin
      # NOTE: work around JRuby and Rubinius bug, where it'd keep calling
      # this FFI::Function, even when the block `break`ed
      if ret != -1
        config      = from_ffi_delegate(zconfig)
        block_value = yield config, level
        ret         = 0 # report success to keep zconfig_execute() going
      end
    rescue StandardError
      # remember exception, so we can raise it later to the ruby code
      # (it can't be raised now, as we have to report failure to
      # zconfig_execute())
      exception = $ERROR_INFO

      ret = -1 # report failure to stop zconfig_execute() immediately
    ensure
      ret ||= -1 # in case of 'break'
    end
    ret
  end
  ffi_delegate.execute(callback, _arg = nil)
  raise exception if exception

  block_value
end

#last_at_depth(level) ⇒ Config?

Finds last item at given level (0 = root).

Returns:

  • (Config) —

    the last config item at given level

  • (nil) —

    if there’s no config item at given level



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# File 'lib/cztop/config/traversing.rb', line 174

def last_at_depth(level)
  ptr = ffi_delegate.at_depth(level)
  return nil if ptr.null?

  from_ffi_delegate(ptr)
end

#locate(path) ⇒ Config?

Finds a config item along a path, relative to the current item.

Parameters:

  • path (String) —

    path (leading slash is optional and will be ignored)

Returns:

  • (Config) —

    the found config item

  • (nil) —

    if there’s no config item under this path



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# File 'lib/cztop/config/traversing.rb', line 163

def locate(path)
  ptr = ffi_delegate.locate(path)
  return nil if ptr.null?

  from_ffi_delegate(ptr)
end

#siblings ⇒ SiblingsAccessor

Note:

Only the “younger” (later in the ZPL file) config items are considered.

Access to this config item’s siblings.

Returns:



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# File 'lib/cztop/config/traversing.rb', line 61

def siblings
  SiblingsAccessor.new(self)
end