Class: AWS::Core::Data

Inherits:
Object
  • Object
show all
Includes:
MethodMissingProxy
Defined in:
lib/aws/core/data.rb

Overview

Data is a light wrapper around a Ruby hash that provides method missing access to the hash contents.

Method Missing Access

You can access hash content with methods if their keys are symbols.

data = AWS::Core::Data.new({ :a => 1, :b => 2, :c => true })
data.a #=> 1
data.b #=> 2
data.c #=> true
data.d #=> raises NoMethodError

Boolean Methods

Given the structure above you can also use question-mark methods.

data.c? #=> true
data.d? #=> raises NoMethodError

Nested Hashes

If the data contains nested hashes you can chain methods into the structure.

data = AWS::Core::Data.new(:a => { :b => { :c => 'abc' }})
data.a.b.c #=> 'abc'

Nested Arrays

Arrays are wrapped in List objects. They ensure any data returned is correctly wrapped so you can continue using method-missing access.

data = AWS::Core::Data.new(
 :people => [
   {:name => 'john'},
   {:name => 'jane'},
]})

data.people[0].name #=> 'john'
data.people[1].name #=> 'jane'

data.people.map(&:name) #=> ['john','jane']

Defined Under Namespace

Modules: MethodMissingProxy Classes: List

Class Method Summary collapse

Instance Method Summary collapse

Methods included from MethodMissingProxy

#[], #dup, #eql?

Constructor Details

#initialize(data) ⇒ Data

Returns a new instance of Data.

Parameters:

  • data (Hash) —

    The ruby hash of data you need wrapped.



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# File 'lib/aws/core/data.rb', line 126

def initialize data
  @data = data
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

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



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# File 'lib/aws/core/data.rb', line 113

def method_missing method_name, *args, &block
  if
    args.empty? and !block_given? and
    key = _remove_question_mark(method_name) and
    @data.has_key?(key)
  then
    Data.cast(@data[key])
  else
    super
  end
end

Class Method Details

.cast(value) ⇒ Data, ...

Given a hash, this method returns a AWS::Core::Data object. Given an Array, this method returns a List object. Everything else is returned as is.

Parameters:

  • value (Object) —

    The value to conditionally wrap.

Returns:

  • (Data, Data::List, Object) —

    Wraps hashes and lists with Data and List objects, all other objects are returned as is.



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# File 'lib/aws/core/data.rb', line 193

def cast value
  case value
  when Hash then Data.new(value)
  when Array then Data::List.new(value)
  else value
  end
end

Instance Method Details

#inspect ⇒ String

Returns an inspection string from the wrapped data.

data = AWS::Core::Data.new({ :a => 1, :b => 2, :c => true })
data.inspect #=> '{:a=>1, :b=>2, :c=>true}'

Returns:

  • (String) 


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# File 'lib/aws/core/data.rb', line 157

def inspect
  @data.inspect
end

#respond_to?(method_name) ⇒ Boolean

Returns true if this data object will respond to the given method name.

Parameters:

  • method_name (String, Symbol)

Returns:

  • (Boolean) —

    Returns true if this data object will respond to the given method name.



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# File 'lib/aws/core/data.rb', line 145

def respond_to? method_name
  @data.key?(_remove_question_mark(method_name)) or
    @data.respond_to?(method_name)
end

#to_a ⇒ Array Also known as: to_ary

Returns:

  • (Array) 


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# File 'lib/aws/core/data.rb', line 137

def to_a
  @data.to_a
end

#to_hash ⇒ Hash Also known as: to_h

Returns contents of this Data object as a raw hash.

Returns:

  • (Hash) —

    Returns contents of this Data object as a raw hash.



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# File 'lib/aws/core/data.rb', line 131

def to_hash
  @data
end