Class: Observed::ConfigDSL

Inherits:
Object
  • Object
show all
Extended by:
Forwardable
Includes:
Configurable
Defined in:
lib/observed/config_dsl.rb

Overview

The DSL to describe Observed’s configuration. context = ConfigDSL.new(builder: the_builder) context.eval_file observed_conf_file(a.k.a user code describes Observed configuration) context.config #=> can be used to instantiate Observed::System

Instance Method Summary collapse

Methods included from Configurable

#configure, #get_attribute_value, #has_attribute_value?, included

Constructor Details

#initialize(args) ⇒ ConfigDSL

Returns a new instance of ConfigDSL.



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# File 'lib/observed/config_dsl.rb', line 23

def initialize(args)
  args[:builder] || fail("The key :builder must exist in #{args}")
  @builder = args[:builder]

  configure(args)
end

Instance Method Details

#config ⇒ Observed::Config

Build and returns the Observed configuration

Returns:



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# File 'lib/observed/config_dsl.rb', line 59

def config
  @builder.build
end

#eval_file(file) ⇒ Object 



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# File 'lib/observed/config_dsl.rb', line 30

def eval_file(file)
  @file = File.expand_path(file)
  working_directory File.dirname(@file)
  logger.debug "Reading the file: #{@file}"
  code = File.read(@file)
  logger.debug "Evaluating: #{code}"
  instance_eval(code, @file)
end

#load!(file) ⇒ Object

Load the file and evaluate the containing code in context of this object(a.k.a DSL). typically ‘observed.conf`.

Parameters:

  • file (String|Pathname) —

    The path to Ruby script containing the code in Observed’s configuration DSL,



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# File 'lib/observed/config_dsl.rb', line 66

def load!(file)
  eval_file file
end

#require_relative(lib) ⇒ Object

The replacement for Ruby’s built-in ‘require_relative`. Although the built-in one can not be used in `eval` or `instance_eval` or etc because there is no `current file` semantics in `eval`, this replacement takes the file which is going to be evaluated as the `current file`. Thanks to this method, we can use `require_relative` in observed.conf files both when it is evaluated with `eval` and when it is evaluated in result of `require`.



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# File 'lib/observed/config_dsl.rb', line 51

def require_relative(lib)
  path = File.expand_path("#{working_directory}/#{lib}")
  logger.debug "Require '#{path}'"
  require path
end

#working_directory(wd = nil) ⇒ Object

The ‘current directory` in which `require_relative` finds source files



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# File 'lib/observed/config_dsl.rb', line 40

def working_directory(wd=nil)
  @working_directory = wd if wd
  @working_directory
end