Module: Cistern::Attributes::InstanceMethods

Included in:
Model
Defined in:
lib/cistern/attributes.rb

Instance Method Summary collapse

Instance Method Details

#attributes ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 164

def attributes
  @attributes ||= {}
end

#attributes=(attributes) ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 168

def attributes=(attributes)
  @attributes = attributes
end

#changed ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 261

def changed
  @changes ||= {}
end

#dirty? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/cistern/attributes.rb', line 253

def dirty?
  changed.any?
end

#dirty_attributes ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 257

def dirty_attributes
  changed.inject({}) { |r, (k, (_, v))| r.merge(k => v) }
end

#dump ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 121

def dump
  Marshal.dump(attributes)
end

#dup ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 172

def dup
  copy = super
  copy.attributes = copy.attributes.dup
  copy
end

#identity ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 178

def identity
  key = self.class.instance_variable_get('@identity')

  public_send(key) if key
end

#identity=(new_identity) ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 184

def identity=(new_identity)
  key = self.class.instance_variable_get('@identity')

  if key
    public_send("#{key}=", new_identity)
  else
    fail ArgumentError, 'Identity not specified'
  end
end

#merge_attributes(new_attributes = {}) ⇒ Object

Update model’s attributes. New attributes take precedence over existing attributes.

This is bst called within a Model#save, when #new_attributes represents a recently presented remote resource. #dirty_attributes is cleared after merging.

Parameters:

  • new_attributes (Hash) (defaults to: {}) —

    attributes to merge with current attributes



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# File 'lib/cistern/attributes.rb', line 200

def merge_attributes(new_attributes = {})
  _merge_attributes(new_attributes)

  changed.clear

  self
end

#new_record? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/cistern/attributes.rb', line 219

def new_record?
  identity.nil?
end

#read_attribute(name) ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 125

def read_attribute(name)
  key = name.to_s.to_sym
  options = self.class.attributes[key]
  default = options[:default]

  # record the attribute was accessed
  if defined?(Cistern::Coverage) && options[:coverage_hits]
    options[:coverage_hits] += 1
  end

  default = Marshal.load(Marshal.dump(default)) unless default.nil?

  attributes.fetch(key, default)
end

#requires(*args) ⇒ Hash

Require specification of certain attributes

Returns:

  • (Hash) —

    of matching attributes

Raises:

  • (ArgumentError) —

    if any requested attribute does not have a value



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# File 'lib/cistern/attributes.rb', line 227

def requires(*args)
  missing, required = missing_attributes(args)

  if missing.length == 1
    fail(ArgumentError, "#{missing.keys.first} is required for this operation")
  elsif missing.any?
    fail(ArgumentError, "#{missing.keys[0...-1].join(', ')} and #{missing.keys[-1]} are required for this operation")
  end

  required
end

#requires_one(*args) ⇒ Hash

Require specification of one or more attributes.

Returns:

  • (Hash) —

    of matching attributes

Raises:

  • (ArgumentError) —

    if no requested attributes have values



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# File 'lib/cistern/attributes.rb', line 243

def requires_one(*args)
  missing, required = missing_attributes(args)

  if missing.length == args.length
    fail(ArgumentError, "#{missing.keys[0...-1].join(', ')} or #{missing.keys[-1]} are required for this operation")
  end

  required
end

#stage_attributes(new_attributes = {}) ⇒ Object

Update model’s attributes. New attributes take precedence over existing attributes.

This is best called within a Model#update, when #new_attributes represents attributes to be presented to a remote service. #dirty_attributes will contain the valid portion of #new_attributes

Parameters:

  • new_attributes (Hash) (defaults to: {}) —

    attributes to merge with current attributes



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# File 'lib/cistern/attributes.rb', line 214

def stage_attributes(new_attributes = {})
  _merge_attributes(new_attributes)
  self
end

#write_attribute(name, value) ⇒ Object 



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# File 'lib/cistern/attributes.rb', line 140

def write_attribute(name, value)
  options = self.class.attributes[name] || {}

  transform = Cistern::Attributes.transforms[options[:squash] ? :squash : :none] ||
              Cistern::Attributes.default_transform

  parser = Cistern::Attributes.parsers[options[:type]] ||
           options[:parser] ||
           Cistern::Attributes.default_parser

  transformed = transform.call(name, value, options)

  new_value = parser.call(transformed, options)
  attribute = name.to_s.to_sym

  previous_value = attributes[attribute]

  attributes[attribute] = new_value

  changed!(attribute, previous_value, new_value)

  new_value
end