Class: JsonFunc

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

Defined Under Namespace

Classes: BadFunctionNameError, BadRootObject, MultipleFunctionsError, ZeroFunctionsError

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(handler) ⇒ JsonFunc

Returns a new instance of JsonFunc.



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# File 'lib/json_func.rb', line 10

def initialize(handler)
  @handler = handler
end

Instance Attribute Details

#handler ⇒ Object (readonly)

Returns the value of attribute handler.



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# File 'lib/json_func.rb', line 8

def handler
  @handler
end

Instance Method Details

#execute(json) ⇒ Object

Raises:



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# File 'lib/json_func.rb', line 14

def execute(json)
  initial_argument = JSON.parse(json)
  raise BadRootObject unless initial_argument.is_a? Hash
  execute_hash(initial_argument)
end

#execute_hash(hash) ⇒ Object

Raises:



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# File 'lib/json_func.rb', line 20

def execute_hash(hash)
  raise MultipleFunctionsError.new(hash.keys) if hash.size > 1
  raise ZeroFunctionsError.new(hash.keys) if hash.size == 0
  func = hash.keys.first
  raise BadFunctionNameError.new(func) unless valid_function?(func)
  arg = hash.values.first
  handler.send(func, *parse_arg(arg))
end

#parse_arg(arg) ⇒ Object 



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# File 'lib/json_func.rb', line 33

def parse_arg(arg)
  case arg
  when Hash
    execute_hash(arg)
  when Array
    arg
  else
    [arg]
  end
end

#valid_function?(func) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/json_func.rb', line 29

def valid_function?(func)
  (handler.public_methods - Object.new.public_methods).map(&:to_s).include? func
end