Module: Protoable::Serialization::ClassMethods

Defined in:
lib/protobuf/activerecord/protoable/serialization.rb

Instance Method Summary collapse

Instance Method Details

#_protobuf_convert_attributes_to_fields(key, value) ⇒ Object

:nodoc:



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# File 'lib/protobuf/activerecord/protoable/serialization.rb', line 24

def _protobuf_convert_attributes_to_fields(key, value)
  return value if value.nil?

  value = case
          when _protobuf_date_column?(key) then
            value.to_time.to_i
          when _protobuf_datetime_column?(key) then
            value.to_i
          when _protobuf_time_column?(key) then
            value.to_i
          when _protobuf_timestamp_column?(key) then
            value.to_i
          else
            value
          end

  return value
end

#field_from_record(field, transformer = nil, &block) ⇒ Object

Define a field transformation from a record. Accepts a Symbol, callable, or block that is called with the record being serialized.

When given a callable or block, it is directly used to convert the field.

When a symbol is given, it extracts the method with the same name.

The callable or method must accept a single parameter, which is the proto message.

Examples:

field_from_record :public_key, :convert_public_key_to_proto
field_from_record :status, lambda { |record| # Do some stuff... }
field_from_record :status do |record|
  # Do some blocky stuff...
end



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# File 'lib/protobuf/activerecord/protoable/serialization.rb', line 60

def field_from_record(field, transformer = nil, &block)
  transformer ||= block

  if transformer.is_a?(Symbol)
    callable = lambda { |value| self.__send__(transformer, value) }
  else
    callable = transformer
  end

  unless callable.respond_to?(:call)
    raise FieldTransformerError, 'Attribute transformers need a callable or block!'
  end

  _protobuf_field_transformers[field.to_sym] = callable
end

#protobuf_message(message = nil, options = {}) ⇒ Object

Define the protobuf message class that should be used to serialize the object to protobuf. Accepts a string or symbol and an options hash.

When protobuf_message is declared, Protoable automatically extracts the fields from the message and automatically adds a to_proto method that serializes the object to protobuf.

The fields that will be automatically serialized can be configured by passing :only or :except in the options hash. If :only is specified, only the specified fields will be serialized. If :except is specified, all field except the specified fields will be serialized.

By default, deprecated fields will be serialized. To exclude deprecated fields, pass :deprecated => false in the options hash.

Examples:

protobuf_message :user_message
protobuf_message "UserMessage"
protobuf_message "Namespaced::UserMessage"
protobuf_message :user_message, :only => [ :guid, :name ]
protobuf_message :user_message, :except => :email_domain
protobuf_message :user_message, :except => :email_domain, :deprecated => false



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# File 'lib/protobuf/activerecord/protoable/serialization.rb', line 99

def protobuf_message(message = nil, options = {})
  unless message.nil?
    @protobuf_message = message.to_s.classify.constantize

    self._protobuf_field_options = options

    define_method(:to_proto) do |options = {}|
      self.class.protobuf_message.new(self.fields_from_record(options))
    end
  end

  @protobuf_message
end