Class: CfnDsl::JSONable

Inherits:
Object
  • Object
show all
Extended by:
Functions
Includes:
Functions, RefCheck
Defined in:
lib/cfndsl/jsonable.rb

Overview

This is the base class for just about everything useful in the DSL. It knows how to turn DSL Objects into the corresponding json, and it lets you create new built in function objects from inside the context of a dsl object.

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Functions

FnAnd, FnBase64, FnEquals, FnFindInMap, FnFormat, FnGetAZs, FnGetAtt, FnIf, FnJoin, FnNot, FnOr, FnSelect, Ref

Methods included from RefCheck

#build_references

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(meth, *args, &_block) ⇒ Object 



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# File 'lib/cfndsl/jsonable.rb', line 176

def method_missing(meth, *args, &_block)
  error = "Undefined symbol: #{meth}"
  error = "#{error}(" + args.inspect[1..-2] + ')' unless args.empty?
  error = "#{error}\n\nTry '#{titleize(meth)}' instead" if incorrect_capitalization?(meth)
  CfnDsl::Errors.error(error, 1)
end

Class Method Details

.external_parameters ⇒ Object 



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# File 'lib/cfndsl/jsonable.rb', line 134

def self.external_parameters
  CfnDsl::ExternalParameters.current
end

Instance Method Details

#as_json(_options = {}) ⇒ Object

Use instance variables to build a json object. Instance variables that begin with a single underscore are elided. Instance variables that begin with two underscores have one of them removed.



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# File 'lib/cfndsl/jsonable.rb', line 146

def as_json(_options = {})
  hash = {}
  instance_variables.each do |var|
    name = var[1..-1]

    if name =~ /^__/
      # if a variable starts with double underscore, strip one off
      name = name[1..-1]
    elsif name =~ /^_/
      # Hide variables that start with single underscore
      name = nil
    end

    hash[name] = instance_variable_get(var) if name
  end
  hash
end

#declare(&block) ⇒ Object 



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# File 'lib/cfndsl/jsonable.rb', line 172

def declare(&block)
  instance_eval(&block) if block_given?
end

#external_parameters ⇒ Object 



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# File 'lib/cfndsl/jsonable.rb', line 138

def external_parameters
  self.class.external_parameters
end

#incorrect_capitalization?(method) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/cfndsl/jsonable.rb', line 183

def incorrect_capitalization?(method)
  method != titleize(method) && respond_to?(titleize(method))
end

#ref_children ⇒ Object 



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# File 'lib/cfndsl/jsonable.rb', line 168

def ref_children
  instance_variables.map { |var| instance_variable_get(var) }
end

#titleize(method) ⇒ Object 



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# File 'lib/cfndsl/jsonable.rb', line 187

def titleize(method)
  method.to_s.clone.tap do |m|
    m[0] = m[0, 1].upcase
  end.to_sym
end

#to_json(*a) ⇒ Object 



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# File 'lib/cfndsl/jsonable.rb', line 164

def to_json(*a)
  as_json.to_json(*a)
end