Class: Dynorm::KeyExpression

Inherits:
Object
  • Object
show all
Defined in:
lib/dynorm/key_expression.rb

Instance Method Summary collapse

Constructor Details

#initialize(attributes) ⇒ KeyExpression

Returns a new instance of KeyExpression.



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# File 'lib/dynorm/key_expression.rb', line 5

def initialize(attributes)
  @attributes = attributes
end

Instance Method Details

#attribute_names ⇒ Object 



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# File 'lib/dynorm/key_expression.rb', line 9

def attribute_names
  @attributes.keys.each_with_object({}) do |value, hash|
    hash["##{value}_name"] = value
  end
end

#attribute_values ⇒ Object 



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# File 'lib/dynorm/key_expression.rb', line 15

def attribute_values
  @attributes.keys.each_with_object({}) do |value, hash|
    hash[":#{value}_value"] = @attributes[value]
  end
end

#key_condition_expression ⇒ Object 



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# File 'lib/dynorm/key_expression.rb', line 21

def key_condition_expression
  @attributes.map do |attr|
    "##{attr[0]}_name = :#{attr[0]}_value"
  end.join(' and ')
end

#params ⇒ Object 



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# File 'lib/dynorm/key_expression.rb', line 27

def params
  {
    expression_attribute_names: attribute_names,
    expression_attribute_values: attribute_values,
    key_condition_expression: key_condition_expression
  }
end