Class: DslBlock::Executor

Inherits:
BasicObject
Defined in:
lib/dsl_block/executor.rb

Overview

The Executor class is designed to run a block of code in isolation for the DslBlock class. By running it in a ‘sandbox’, the block of code cannot inadvertently access protected and private methods within the DslBlock without explicate declaration by the DslBlock. To the user, it will appear that the block runs directly in the DslBlock but in a partly restricted manner if they care to investigate. In this fashion, executor is effectively a transparent proxy.

Instance Method Summary collapse

Constructor Details

#initialize(dsl_block) ⇒ Executor

Returns a new instance of Executor.



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# File 'lib/dsl_block/executor.rb', line 12

def initialize(dsl_block)
  @dsl_block = dsl_block
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method, *args, &block) ⇒ Object 



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# File 'lib/dsl_block/executor.rb', line 16

def method_missing(method, *args, &block)
  # If the dsl block lists the method as a callable command
  if @dsl_block._commands.include?(method)
    # Attempt to call it
    begin
      @dsl_block.send(method, *args, &block)
    rescue => e
      # If there is any type of error, remove ourselves from the callstack to reduce confusion.
      e.set_backtrace(::Kernel.caller.select { |x| !x.include?(__FILE__)})
      ::Kernel.raise e
    end
  else
    # Otherwise raise a no method error as if the method does not really exist, regardless of reality.
    name_error = ::NameError.new("undefined local variable or method `#{method}' for #{self.inspect}")
    name_error.set_backtrace(::Kernel.caller.select { |x| !x.include?(__FILE__)})
    ::Kernel::raise name_error
  end
end